diff --git a/framework-t/Sources.bp b/framework-t/Sources.bp
index 2363a9f..9c07f39 100644
--- a/framework-t/Sources.bp
+++ b/framework-t/Sources.bp
@@ -19,11 +19,58 @@
     default_applicable_licenses: ["Android-Apache-2.0"],
 }
 
+// NetworkStats related libraries.
+
+filegroup {
+    name: "framework-connectivity-netstats-internal-sources",
+    srcs: [
+        "src/android/app/usage/*.java",
+        "src/android/net/DataUsage*.*",
+        "src/android/net/INetworkStats*.*",
+        "src/android/net/NetworkIdentity*.java",
+        "src/android/net/NetworkStateSnapshot.*",
+        "src/android/net/NetworkStats*.*",
+        "src/android/net/NetworkTemplate.*",
+        "src/android/net/TrafficStats.java",
+        "src/android/net/UnderlyingNetworkInfo.*",
+        "src/android/net/netstats/**/*.*",
+    ],
+    path: "src",
+    visibility: [
+        "//visibility:private",
+    ],
+}
+
+filegroup {
+    name: "framework-connectivity-netstats-aidl-export-sources",
+    srcs: [
+        "aidl-export/android/net/NetworkStats.aidl",
+        "aidl-export/android/net/NetworkTemplate.aidl",
+    ],
+    path: "aidl-export",
+    visibility: [
+        "//visibility:private",
+    ],
+}
+
+filegroup {
+    name: "framework-connectivity-netstats-sources",
+    srcs: [
+        ":framework-connectivity-netstats-internal-sources",
+        ":framework-connectivity-netstats-aidl-export-sources",
+    ],
+    visibility: [
+        "//visibility:private",
+    ],
+}
+
+// Nsd related libraries.
+
 filegroup {
     name: "framework-connectivity-nsd-internal-sources",
     srcs: [
-        "src/**/*.java",
-        "src/**/*.aidl",
+        "src/android/net/nsd/*.aidl",
+        "src/android/net/nsd/*.java",
     ],
     path: "src",
     visibility: [
@@ -34,7 +81,7 @@
 filegroup {
     name: "framework-connectivity-nsd-aidl-export-sources",
     srcs: [
-        "aidl-export/**/*.aidl",
+        "aidl-export/android/net/nsd/*.aidl",
     ],
     path: "aidl-export",
     visibility: [
@@ -49,6 +96,19 @@
         ":framework-connectivity-nsd-aidl-export-sources",
     ],
     visibility: [
-        "//frameworks/base",
+        "//visibility:private",
     ],
 }
+
+// Connectivity-T common libraries.
+
+filegroup {
+    name: "framework-connectivity-tiramisu-sources",
+    srcs: [
+        ":framework-connectivity-netstats-sources",
+        ":framework-connectivity-nsd-sources",
+    ],
+    visibility: [
+        "//frameworks/base",
+    ],
+}
\ No newline at end of file
diff --git a/framework-t/src/android/app/usage/NetworkStats.java b/framework-t/src/android/app/usage/NetworkStats.java
new file mode 100644
index 0000000..216a4a0
--- /dev/null
+++ b/framework-t/src/android/app/usage/NetworkStats.java
@@ -0,0 +1,717 @@
+/**
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy
+ * of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+
+package android.app.usage;
+
+import android.annotation.IntDef;
+import android.content.Context;
+import android.net.INetworkStatsService;
+import android.net.INetworkStatsSession;
+import android.net.NetworkStatsHistory;
+import android.net.NetworkTemplate;
+import android.net.TrafficStats;
+import android.os.RemoteException;
+import android.util.IntArray;
+import android.util.Log;
+
+import dalvik.system.CloseGuard;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/**
+ * Class providing enumeration over buckets of network usage statistics. {@link NetworkStats} objects
+ * are returned as results to various queries in {@link NetworkStatsManager}.
+ */
+public final class NetworkStats implements AutoCloseable {
+    private final static String TAG = "NetworkStats";
+
+    private final CloseGuard mCloseGuard = CloseGuard.get();
+
+    /**
+     * Start timestamp of stats collected
+     */
+    private final long mStartTimeStamp;
+
+    /**
+     * End timestamp of stats collected
+     */
+    private final long mEndTimeStamp;
+
+    /**
+     * Non-null array indicates the query enumerates over uids.
+     */
+    private int[] mUids;
+
+    /**
+     * Index of the current uid in mUids when doing uid enumeration or a single uid value,
+     * depending on query type.
+     */
+    private int mUidOrUidIndex;
+
+    /**
+     * Tag id in case if was specified in the query.
+     */
+    private int mTag = android.net.NetworkStats.TAG_NONE;
+
+    /**
+     * State in case it was not specified in the query.
+     */
+    private int mState = Bucket.STATE_ALL;
+
+    /**
+     * The session while the query requires it, null if all the stats have been collected or close()
+     * has been called.
+     */
+    private INetworkStatsSession mSession;
+    private NetworkTemplate mTemplate;
+
+    /**
+     * Results of a summary query.
+     */
+    private android.net.NetworkStats mSummary = null;
+
+    /**
+     * Results of detail queries.
+     */
+    private NetworkStatsHistory mHistory = null;
+
+    /**
+     * Where we are in enumerating over the current result.
+     */
+    private int mEnumerationIndex = 0;
+
+    /**
+     * Recycling entry objects to prevent heap fragmentation.
+     */
+    private android.net.NetworkStats.Entry mRecycledSummaryEntry = null;
+    private NetworkStatsHistory.Entry mRecycledHistoryEntry = null;
+
+    /** @hide */
+    NetworkStats(Context context, NetworkTemplate template, int flags, long startTimestamp,
+            long endTimestamp, INetworkStatsService statsService)
+            throws RemoteException, SecurityException {
+        // Open network stats session
+        mSession = statsService.openSessionForUsageStats(flags, context.getOpPackageName());
+        mCloseGuard.open("close");
+        mTemplate = template;
+        mStartTimeStamp = startTimestamp;
+        mEndTimeStamp = endTimestamp;
+    }
+
+    @Override
+    protected void finalize() throws Throwable {
+        try {
+            if (mCloseGuard != null) {
+                mCloseGuard.warnIfOpen();
+            }
+            close();
+        } finally {
+            super.finalize();
+        }
+    }
+
+    // -------------------------BEGINNING OF PUBLIC API-----------------------------------
+
+    /**
+     * Buckets are the smallest elements of a query result. As some dimensions of a result may be
+     * aggregated (e.g. time or state) some values may be equal across all buckets.
+     */
+    public static class Bucket {
+        /** @hide */
+        @IntDef(prefix = { "STATE_" }, value = {
+                STATE_ALL,
+                STATE_DEFAULT,
+                STATE_FOREGROUND
+        })
+        @Retention(RetentionPolicy.SOURCE)
+        public @interface State {}
+
+        /**
+         * Combined usage across all states.
+         */
+        public static final int STATE_ALL = -1;
+
+        /**
+         * Usage not accounted for in any other state.
+         */
+        public static final int STATE_DEFAULT = 0x1;
+
+        /**
+         * Foreground usage.
+         */
+        public static final int STATE_FOREGROUND = 0x2;
+
+        /**
+         * Special UID value for aggregate/unspecified.
+         */
+        public static final int UID_ALL = android.net.NetworkStats.UID_ALL;
+
+        /**
+         * Special UID value for removed apps.
+         */
+        public static final int UID_REMOVED = TrafficStats.UID_REMOVED;
+
+        /**
+         * Special UID value for data usage by tethering.
+         */
+        public static final int UID_TETHERING = TrafficStats.UID_TETHERING;
+
+        /** @hide */
+        @IntDef(prefix = { "METERED_" }, value = {
+                METERED_ALL,
+                METERED_NO,
+                METERED_YES
+        })
+        @Retention(RetentionPolicy.SOURCE)
+        public @interface Metered {}
+
+        /**
+         * Combined usage across all metered states. Covers metered and unmetered usage.
+         */
+        public static final int METERED_ALL = -1;
+
+        /**
+         * Usage that occurs on an unmetered network.
+         */
+        public static final int METERED_NO = 0x1;
+
+        /**
+         * Usage that occurs on a metered network.
+         *
+         * <p>A network is classified as metered when the user is sensitive to heavy data usage on
+         * that connection.
+         */
+        public static final int METERED_YES = 0x2;
+
+        /** @hide */
+        @IntDef(prefix = { "ROAMING_" }, value = {
+                ROAMING_ALL,
+                ROAMING_NO,
+                ROAMING_YES
+        })
+        @Retention(RetentionPolicy.SOURCE)
+        public @interface Roaming {}
+
+        /**
+         * Combined usage across all roaming states. Covers both roaming and non-roaming usage.
+         */
+        public static final int ROAMING_ALL = -1;
+
+        /**
+         * Usage that occurs on a home, non-roaming network.
+         *
+         * <p>Any cellular usage in this bucket was incurred while the device was connected to a
+         * tower owned or operated by the user's wireless carrier, or a tower that the user's
+         * wireless carrier has indicated should be treated as a home network regardless.
+         *
+         * <p>This is also the default value for network types that do not support roaming.
+         */
+        public static final int ROAMING_NO = 0x1;
+
+        /**
+         * Usage that occurs on a roaming network.
+         *
+         * <p>Any cellular usage in this bucket as incurred while the device was roaming on another
+         * carrier's network, for which additional charges may apply.
+         */
+        public static final int ROAMING_YES = 0x2;
+
+        /** @hide */
+        @IntDef(prefix = { "DEFAULT_NETWORK_" }, value = {
+                DEFAULT_NETWORK_ALL,
+                DEFAULT_NETWORK_NO,
+                DEFAULT_NETWORK_YES
+        })
+        @Retention(RetentionPolicy.SOURCE)
+        public @interface DefaultNetworkStatus {}
+
+        /**
+         * Combined usage for this network regardless of default network status.
+         */
+        public static final int DEFAULT_NETWORK_ALL = -1;
+
+        /**
+         * Usage that occurs while this network is not a default network.
+         *
+         * <p>This implies that the app responsible for this usage requested that it occur on a
+         * specific network different from the one(s) the system would have selected for it.
+         */
+        public static final int DEFAULT_NETWORK_NO = 0x1;
+
+        /**
+         * Usage that occurs while this network is a default network.
+         *
+         * <p>This implies that the app either did not select a specific network for this usage,
+         * or it selected a network that the system could have selected for app traffic.
+         */
+        public static final int DEFAULT_NETWORK_YES = 0x2;
+
+        /**
+         * Special TAG value for total data across all tags
+         */
+        public static final int TAG_NONE = android.net.NetworkStats.TAG_NONE;
+
+        private int mUid;
+        private int mTag;
+        private int mState;
+        private int mDefaultNetworkStatus;
+        private int mMetered;
+        private int mRoaming;
+        private long mBeginTimeStamp;
+        private long mEndTimeStamp;
+        private long mRxBytes;
+        private long mRxPackets;
+        private long mTxBytes;
+        private long mTxPackets;
+
+        private static int convertSet(@State int state) {
+            switch (state) {
+                case STATE_ALL: return android.net.NetworkStats.SET_ALL;
+                case STATE_DEFAULT: return android.net.NetworkStats.SET_DEFAULT;
+                case STATE_FOREGROUND: return android.net.NetworkStats.SET_FOREGROUND;
+            }
+            return 0;
+        }
+
+        private static @State int convertState(int networkStatsSet) {
+            switch (networkStatsSet) {
+                case android.net.NetworkStats.SET_ALL : return STATE_ALL;
+                case android.net.NetworkStats.SET_DEFAULT : return STATE_DEFAULT;
+                case android.net.NetworkStats.SET_FOREGROUND : return STATE_FOREGROUND;
+            }
+            return 0;
+        }
+
+        private static int convertUid(int uid) {
+            switch (uid) {
+                case TrafficStats.UID_REMOVED: return UID_REMOVED;
+                case TrafficStats.UID_TETHERING: return UID_TETHERING;
+            }
+            return uid;
+        }
+
+        private static int convertTag(int tag) {
+            switch (tag) {
+                case android.net.NetworkStats.TAG_NONE: return TAG_NONE;
+            }
+            return tag;
+        }
+
+        private static @Metered int convertMetered(int metered) {
+            switch (metered) {
+                case android.net.NetworkStats.METERED_ALL : return METERED_ALL;
+                case android.net.NetworkStats.METERED_NO: return METERED_NO;
+                case android.net.NetworkStats.METERED_YES: return METERED_YES;
+            }
+            return 0;
+        }
+
+        private static @Roaming int convertRoaming(int roaming) {
+            switch (roaming) {
+                case android.net.NetworkStats.ROAMING_ALL : return ROAMING_ALL;
+                case android.net.NetworkStats.ROAMING_NO: return ROAMING_NO;
+                case android.net.NetworkStats.ROAMING_YES: return ROAMING_YES;
+            }
+            return 0;
+        }
+
+        private static @DefaultNetworkStatus int convertDefaultNetworkStatus(
+                int defaultNetworkStatus) {
+            switch (defaultNetworkStatus) {
+                case android.net.NetworkStats.DEFAULT_NETWORK_ALL : return DEFAULT_NETWORK_ALL;
+                case android.net.NetworkStats.DEFAULT_NETWORK_NO: return DEFAULT_NETWORK_NO;
+                case android.net.NetworkStats.DEFAULT_NETWORK_YES: return DEFAULT_NETWORK_YES;
+            }
+            return 0;
+        }
+
+        public Bucket() {
+        }
+
+        /**
+         * Key of the bucket. Usually an app uid or one of the following special values:<p />
+         * <ul>
+         * <li>{@link #UID_REMOVED}</li>
+         * <li>{@link #UID_TETHERING}</li>
+         * <li>{@link android.os.Process#SYSTEM_UID}</li>
+         * </ul>
+         * @return Bucket key.
+         */
+        public int getUid() {
+            return mUid;
+        }
+
+        /**
+         * Tag of the bucket.<p />
+         * @return Bucket tag.
+         */
+        public int getTag() {
+            return mTag;
+        }
+
+        /**
+         * Usage state. One of the following values:<p/>
+         * <ul>
+         * <li>{@link #STATE_ALL}</li>
+         * <li>{@link #STATE_DEFAULT}</li>
+         * <li>{@link #STATE_FOREGROUND}</li>
+         * </ul>
+         * @return Usage state.
+         */
+        public @State int getState() {
+            return mState;
+        }
+
+        /**
+         * Metered state. One of the following values:<p/>
+         * <ul>
+         * <li>{@link #METERED_ALL}</li>
+         * <li>{@link #METERED_NO}</li>
+         * <li>{@link #METERED_YES}</li>
+         * </ul>
+         * <p>A network is classified as metered when the user is sensitive to heavy data usage on
+         * that connection. Apps may warn before using these networks for large downloads. The
+         * metered state can be set by the user within data usage network restrictions.
+         */
+        public @Metered int getMetered() {
+            return mMetered;
+        }
+
+        /**
+         * Roaming state. One of the following values:<p/>
+         * <ul>
+         * <li>{@link #ROAMING_ALL}</li>
+         * <li>{@link #ROAMING_NO}</li>
+         * <li>{@link #ROAMING_YES}</li>
+         * </ul>
+         */
+        public @Roaming int getRoaming() {
+            return mRoaming;
+        }
+
+        /**
+         * Default network status. One of the following values:<p/>
+         * <ul>
+         * <li>{@link #DEFAULT_NETWORK_ALL}</li>
+         * <li>{@link #DEFAULT_NETWORK_NO}</li>
+         * <li>{@link #DEFAULT_NETWORK_YES}</li>
+         * </ul>
+         */
+        public @DefaultNetworkStatus int getDefaultNetworkStatus() {
+            return mDefaultNetworkStatus;
+        }
+
+        /**
+         * Start timestamp of the bucket's time interval. Defined in terms of "Unix time", see
+         * {@link java.lang.System#currentTimeMillis}.
+         * @return Start of interval.
+         */
+        public long getStartTimeStamp() {
+            return mBeginTimeStamp;
+        }
+
+        /**
+         * End timestamp of the bucket's time interval. Defined in terms of "Unix time", see
+         * {@link java.lang.System#currentTimeMillis}.
+         * @return End of interval.
+         */
+        public long getEndTimeStamp() {
+            return mEndTimeStamp;
+        }
+
+        /**
+         * Number of bytes received during the bucket's time interval. Statistics are measured at
+         * the network layer, so they include both TCP and UDP usage.
+         * @return Number of bytes.
+         */
+        public long getRxBytes() {
+            return mRxBytes;
+        }
+
+        /**
+         * Number of bytes transmitted during the bucket's time interval. Statistics are measured at
+         * the network layer, so they include both TCP and UDP usage.
+         * @return Number of bytes.
+         */
+        public long getTxBytes() {
+            return mTxBytes;
+        }
+
+        /**
+         * Number of packets received during the bucket's time interval. Statistics are measured at
+         * the network layer, so they include both TCP and UDP usage.
+         * @return Number of packets.
+         */
+        public long getRxPackets() {
+            return mRxPackets;
+        }
+
+        /**
+         * Number of packets transmitted during the bucket's time interval. Statistics are measured
+         * at the network layer, so they include both TCP and UDP usage.
+         * @return Number of packets.
+         */
+        public long getTxPackets() {
+            return mTxPackets;
+        }
+    }
+
+    /**
+     * Fills the recycled bucket with data of the next bin in the enumeration.
+     * @param bucketOut Bucket to be filled with data.
+     * @return true if successfully filled the bucket, false otherwise.
+     */
+    public boolean getNextBucket(Bucket bucketOut) {
+        if (mSummary != null) {
+            return getNextSummaryBucket(bucketOut);
+        } else {
+            return getNextHistoryBucket(bucketOut);
+        }
+    }
+
+    /**
+     * Check if it is possible to ask for a next bucket in the enumeration.
+     * @return true if there is at least one more bucket.
+     */
+    public boolean hasNextBucket() {
+        if (mSummary != null) {
+            return mEnumerationIndex < mSummary.size();
+        } else if (mHistory != null) {
+            return mEnumerationIndex < mHistory.size()
+                    || hasNextUid();
+        }
+        return false;
+    }
+
+    /**
+     * Closes the enumeration. Call this method before this object gets out of scope.
+     */
+    @Override
+    public void close() {
+        if (mSession != null) {
+            try {
+                mSession.close();
+            } catch (RemoteException e) {
+                Log.w(TAG, e);
+                // Otherwise, meh
+            }
+        }
+        mSession = null;
+        if (mCloseGuard != null) {
+            mCloseGuard.close();
+        }
+    }
+
+    // -------------------------END OF PUBLIC API-----------------------------------
+
+    /**
+     * Collects device summary results into a Bucket.
+     * @throws RemoteException
+     */
+    Bucket getDeviceSummaryForNetwork() throws RemoteException {
+        mSummary = mSession.getDeviceSummaryForNetwork(mTemplate, mStartTimeStamp, mEndTimeStamp);
+
+        // Setting enumeration index beyond end to avoid accidental enumeration over data that does
+        // not belong to the calling user.
+        mEnumerationIndex = mSummary.size();
+
+        return getSummaryAggregate();
+    }
+
+    /**
+     * Collects summary results and sets summary enumeration mode.
+     * @throws RemoteException
+     */
+    void startSummaryEnumeration() throws RemoteException {
+        mSummary = mSession.getSummaryForAllUid(mTemplate, mStartTimeStamp, mEndTimeStamp,
+                false /* includeTags */);
+        mEnumerationIndex = 0;
+    }
+
+    /**
+     * Collects history results for uid and resets history enumeration index.
+     */
+    void startHistoryEnumeration(int uid, int tag, int state) {
+        mHistory = null;
+        try {
+            mHistory = mSession.getHistoryIntervalForUid(mTemplate, uid,
+                    Bucket.convertSet(state), tag, NetworkStatsHistory.FIELD_ALL,
+                    mStartTimeStamp, mEndTimeStamp);
+            setSingleUidTagState(uid, tag, state);
+        } catch (RemoteException e) {
+            Log.w(TAG, e);
+            // Leaving mHistory null
+        }
+        mEnumerationIndex = 0;
+    }
+
+    /**
+     * Starts uid enumeration for current user.
+     * @throws RemoteException
+     */
+    void startUserUidEnumeration() throws RemoteException {
+        // TODO: getRelevantUids should be sensitive to time interval. When that's done,
+        //       the filtering logic below can be removed.
+        int[] uids = mSession.getRelevantUids();
+        // Filtering of uids with empty history.
+        IntArray filteredUids = new IntArray(uids.length);
+        for (int uid : uids) {
+            try {
+                NetworkStatsHistory history = mSession.getHistoryIntervalForUid(mTemplate, uid,
+                        android.net.NetworkStats.SET_ALL, android.net.NetworkStats.TAG_NONE,
+                        NetworkStatsHistory.FIELD_ALL, mStartTimeStamp, mEndTimeStamp);
+                if (history != null && history.size() > 0) {
+                    filteredUids.add(uid);
+                }
+            } catch (RemoteException e) {
+                Log.w(TAG, "Error while getting history of uid " + uid, e);
+            }
+        }
+        mUids = filteredUids.toArray();
+        mUidOrUidIndex = -1;
+        stepHistory();
+    }
+
+    /**
+     * Steps to next uid in enumeration and collects history for that.
+     */
+    private void stepHistory(){
+        if (hasNextUid()) {
+            stepUid();
+            mHistory = null;
+            try {
+                mHistory = mSession.getHistoryIntervalForUid(mTemplate, getUid(),
+                        android.net.NetworkStats.SET_ALL, android.net.NetworkStats.TAG_NONE,
+                        NetworkStatsHistory.FIELD_ALL, mStartTimeStamp, mEndTimeStamp);
+            } catch (RemoteException e) {
+                Log.w(TAG, e);
+                // Leaving mHistory null
+            }
+            mEnumerationIndex = 0;
+        }
+    }
+
+    private void fillBucketFromSummaryEntry(Bucket bucketOut) {
+        bucketOut.mUid = Bucket.convertUid(mRecycledSummaryEntry.uid);
+        bucketOut.mTag = Bucket.convertTag(mRecycledSummaryEntry.tag);
+        bucketOut.mState = Bucket.convertState(mRecycledSummaryEntry.set);
+        bucketOut.mDefaultNetworkStatus = Bucket.convertDefaultNetworkStatus(
+                mRecycledSummaryEntry.defaultNetwork);
+        bucketOut.mMetered = Bucket.convertMetered(mRecycledSummaryEntry.metered);
+        bucketOut.mRoaming = Bucket.convertRoaming(mRecycledSummaryEntry.roaming);
+        bucketOut.mBeginTimeStamp = mStartTimeStamp;
+        bucketOut.mEndTimeStamp = mEndTimeStamp;
+        bucketOut.mRxBytes = mRecycledSummaryEntry.rxBytes;
+        bucketOut.mRxPackets = mRecycledSummaryEntry.rxPackets;
+        bucketOut.mTxBytes = mRecycledSummaryEntry.txBytes;
+        bucketOut.mTxPackets = mRecycledSummaryEntry.txPackets;
+    }
+
+    /**
+     * Getting the next item in summary enumeration.
+     * @param bucketOut Next item will be set here.
+     * @return true if a next item could be set.
+     */
+    private boolean getNextSummaryBucket(Bucket bucketOut) {
+        if (bucketOut != null && mEnumerationIndex < mSummary.size()) {
+            mRecycledSummaryEntry = mSummary.getValues(mEnumerationIndex++, mRecycledSummaryEntry);
+            fillBucketFromSummaryEntry(bucketOut);
+            return true;
+        }
+        return false;
+    }
+
+    Bucket getSummaryAggregate() {
+        if (mSummary == null) {
+            return null;
+        }
+        Bucket bucket = new Bucket();
+        if (mRecycledSummaryEntry == null) {
+            mRecycledSummaryEntry = new android.net.NetworkStats.Entry();
+        }
+        mSummary.getTotal(mRecycledSummaryEntry);
+        fillBucketFromSummaryEntry(bucket);
+        return bucket;
+    }
+
+    /**
+     * Getting the next item in a history enumeration.
+     * @param bucketOut Next item will be set here.
+     * @return true if a next item could be set.
+     */
+    private boolean getNextHistoryBucket(Bucket bucketOut) {
+        if (bucketOut != null && mHistory != null) {
+            if (mEnumerationIndex < mHistory.size()) {
+                mRecycledHistoryEntry = mHistory.getValues(mEnumerationIndex++,
+                        mRecycledHistoryEntry);
+                bucketOut.mUid = Bucket.convertUid(getUid());
+                bucketOut.mTag = Bucket.convertTag(mTag);
+                bucketOut.mState = mState;
+                bucketOut.mDefaultNetworkStatus = Bucket.DEFAULT_NETWORK_ALL;
+                bucketOut.mMetered = Bucket.METERED_ALL;
+                bucketOut.mRoaming = Bucket.ROAMING_ALL;
+                bucketOut.mBeginTimeStamp = mRecycledHistoryEntry.bucketStart;
+                bucketOut.mEndTimeStamp = mRecycledHistoryEntry.bucketStart +
+                        mRecycledHistoryEntry.bucketDuration;
+                bucketOut.mRxBytes = mRecycledHistoryEntry.rxBytes;
+                bucketOut.mRxPackets = mRecycledHistoryEntry.rxPackets;
+                bucketOut.mTxBytes = mRecycledHistoryEntry.txBytes;
+                bucketOut.mTxPackets = mRecycledHistoryEntry.txPackets;
+                return true;
+            } else if (hasNextUid()) {
+                stepHistory();
+                return getNextHistoryBucket(bucketOut);
+            }
+        }
+        return false;
+    }
+
+    // ------------------ UID LOGIC------------------------
+
+    private boolean isUidEnumeration() {
+        return mUids != null;
+    }
+
+    private boolean hasNextUid() {
+        return isUidEnumeration() && (mUidOrUidIndex + 1) < mUids.length;
+    }
+
+    private int getUid() {
+        // Check if uid enumeration.
+        if (isUidEnumeration()) {
+            if (mUidOrUidIndex < 0 || mUidOrUidIndex >= mUids.length) {
+                throw new IndexOutOfBoundsException(
+                        "Index=" + mUidOrUidIndex + " mUids.length=" + mUids.length);
+            }
+            return mUids[mUidOrUidIndex];
+        }
+        // Single uid mode.
+        return mUidOrUidIndex;
+    }
+
+    private void setSingleUidTagState(int uid, int tag, int state) {
+        mUidOrUidIndex = uid;
+        mTag = tag;
+        mState = state;
+    }
+
+    private void stepUid() {
+        if (mUids != null) {
+            ++mUidOrUidIndex;
+        }
+    }
+}
diff --git a/framework-t/src/android/app/usage/NetworkStatsManager.java b/framework-t/src/android/app/usage/NetworkStatsManager.java
new file mode 100644
index 0000000..8a6c85d
--- /dev/null
+++ b/framework-t/src/android/app/usage/NetworkStatsManager.java
@@ -0,0 +1,767 @@
+/**
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy
+ * of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+
+package android.app.usage;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.RequiresPermission;
+import android.annotation.SystemApi;
+import android.annotation.SystemService;
+import android.annotation.TestApi;
+import android.annotation.WorkerThread;
+import android.app.usage.NetworkStats.Bucket;
+import android.compat.annotation.UnsupportedAppUsage;
+import android.content.Context;
+import android.net.ConnectivityManager;
+import android.net.DataUsageRequest;
+import android.net.INetworkStatsService;
+import android.net.Network;
+import android.net.NetworkStack;
+import android.net.NetworkStateSnapshot;
+import android.net.NetworkTemplate;
+import android.net.UnderlyingNetworkInfo;
+import android.net.netstats.provider.INetworkStatsProviderCallback;
+import android.net.netstats.provider.NetworkStatsProvider;
+import android.os.Binder;
+import android.os.Build;
+import android.os.Handler;
+import android.os.Looper;
+import android.os.Message;
+import android.os.Messenger;
+import android.os.RemoteException;
+import android.os.ServiceManager;
+import android.os.ServiceManager.ServiceNotFoundException;
+import android.telephony.TelephonyManager;
+import android.text.TextUtils;
+import android.util.DataUnit;
+import android.util.Log;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.net.module.util.NetworkIdentityUtils;
+
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * Provides access to network usage history and statistics. Usage data is collected in
+ * discrete bins of time called 'Buckets'. See {@link NetworkStats.Bucket} for details.
+ * <p />
+ * Queries can define a time interval in the form of start and end timestamps (Long.MIN_VALUE and
+ * Long.MAX_VALUE can be used to simulate open ended intervals). By default, apps can only obtain
+ * data about themselves. See the below note for special cases in which apps can obtain data about
+ * other applications.
+ * <h3>
+ * Summary queries
+ * </h3>
+ * {@link #querySummaryForDevice} <p />
+ * {@link #querySummaryForUser} <p />
+ * {@link #querySummary} <p />
+ * These queries aggregate network usage across the whole interval. Therefore there will be only one
+ * bucket for a particular key, state, metered and roaming combination. In case of the user-wide
+ * and device-wide summaries a single bucket containing the totalised network usage is returned.
+ * <h3>
+ * History queries
+ * </h3>
+ * {@link #queryDetailsForUid} <p />
+ * {@link #queryDetails} <p />
+ * These queries do not aggregate over time but do aggregate over state, metered and roaming.
+ * Therefore there can be multiple buckets for a particular key. However, all Buckets will have
+ * {@code state} {@link NetworkStats.Bucket#STATE_ALL},
+ * {@code defaultNetwork} {@link NetworkStats.Bucket#DEFAULT_NETWORK_ALL},
+ * {@code metered } {@link NetworkStats.Bucket#METERED_ALL},
+ * {@code roaming} {@link NetworkStats.Bucket#ROAMING_ALL}.
+ * <p />
+ * <b>NOTE:</b> Calling {@link #querySummaryForDevice} or accessing stats for apps other than the
+ * calling app requires the permission {@link android.Manifest.permission#PACKAGE_USAGE_STATS},
+ * which is a system-level permission and will not be granted to third-party apps. However,
+ * declaring the permission implies intention to use the API and the user of the device can grant
+ * permission through the Settings application.
+ * <p />
+ * Profile owner apps are automatically granted permission to query data on the profile they manage
+ * (that is, for any query except {@link #querySummaryForDevice}). Device owner apps and carrier-
+ * privileged apps likewise get access to usage data for all users on the device.
+ * <p />
+ * In addition to tethering usage, usage by removed users and apps, and usage by the system
+ * is also included in the results for callers with one of these higher levels of access.
+ * <p />
+ * <b>NOTE:</b> Prior to API level {@value android.os.Build.VERSION_CODES#N}, all calls to these APIs required
+ * the above permission, even to access an app's own data usage, and carrier-privileged apps were
+ * not included.
+ */
+@SystemService(Context.NETWORK_STATS_SERVICE)
+public class NetworkStatsManager {
+    private static final String TAG = "NetworkStatsManager";
+    private static final boolean DBG = false;
+
+    /** @hide */
+    public static final int CALLBACK_LIMIT_REACHED = 0;
+    /** @hide */
+    public static final int CALLBACK_RELEASED = 1;
+
+    /**
+     * Minimum data usage threshold for registering usage callbacks.
+     *
+     * Requests registered with a threshold lower than this will only be triggered once this minimum
+     * is reached.
+     * @hide
+     */
+    public static final long MIN_THRESHOLD_BYTES = DataUnit.MEBIBYTES.toBytes(2);
+
+    private final Context mContext;
+    private final INetworkStatsService mService;
+
+    /** @hide */
+    public static final int FLAG_POLL_ON_OPEN = 1 << 0;
+    /** @hide */
+    public static final int FLAG_POLL_FORCE = 1 << 1;
+    /** @hide */
+    public static final int FLAG_AUGMENT_WITH_SUBSCRIPTION_PLAN = 1 << 2;
+
+    private int mFlags;
+
+    /**
+     * {@hide}
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public NetworkStatsManager(Context context) throws ServiceNotFoundException {
+        this(context, INetworkStatsService.Stub.asInterface(
+                ServiceManager.getServiceOrThrow(Context.NETWORK_STATS_SERVICE)));
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public NetworkStatsManager(Context context, INetworkStatsService service) {
+        mContext = context;
+        mService = service;
+        setPollOnOpen(true);
+    }
+
+    /** @hide */
+    public void setPollOnOpen(boolean pollOnOpen) {
+        if (pollOnOpen) {
+            mFlags |= FLAG_POLL_ON_OPEN;
+        } else {
+            mFlags &= ~FLAG_POLL_ON_OPEN;
+        }
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    @TestApi
+    public void setPollForce(boolean pollForce) {
+        if (pollForce) {
+            mFlags |= FLAG_POLL_FORCE;
+        } else {
+            mFlags &= ~FLAG_POLL_FORCE;
+        }
+    }
+
+    /** @hide */
+    public void setAugmentWithSubscriptionPlan(boolean augmentWithSubscriptionPlan) {
+        if (augmentWithSubscriptionPlan) {
+            mFlags |= FLAG_AUGMENT_WITH_SUBSCRIPTION_PLAN;
+        } else {
+            mFlags &= ~FLAG_AUGMENT_WITH_SUBSCRIPTION_PLAN;
+        }
+    }
+
+    /** @hide */
+    public Bucket querySummaryForDevice(NetworkTemplate template,
+            long startTime, long endTime) throws SecurityException, RemoteException {
+        Bucket bucket = null;
+        NetworkStats stats = new NetworkStats(mContext, template, mFlags, startTime, endTime,
+                mService);
+        bucket = stats.getDeviceSummaryForNetwork();
+
+        stats.close();
+        return bucket;
+    }
+
+    /**
+     * Query network usage statistics summaries. Result is summarised data usage for the whole
+     * device. Result is a single Bucket aggregated over time, state, uid, tag, metered, and
+     * roaming. This means the bucket's start and end timestamp are going to be the same as the
+     * 'startTime' and 'endTime' parameters. State is going to be
+     * {@link NetworkStats.Bucket#STATE_ALL}, uid {@link NetworkStats.Bucket#UID_ALL},
+     * tag {@link NetworkStats.Bucket#TAG_NONE},
+     * default network {@link NetworkStats.Bucket#DEFAULT_NETWORK_ALL},
+     * metered {@link NetworkStats.Bucket#METERED_ALL},
+     * and roaming {@link NetworkStats.Bucket#ROAMING_ALL}.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param networkType As defined in {@link ConnectivityManager}, e.g.
+     *            {@link ConnectivityManager#TYPE_MOBILE}, {@link ConnectivityManager#TYPE_WIFI}
+     *            etc.
+     * @param subscriberId If applicable, the subscriber id of the network interface.
+     *                     <p>Starting with API level 29, the {@code subscriberId} is guarded by
+     *                     additional restrictions. Calling apps that do not meet the new
+     *                     requirements to access the {@code subscriberId} can provide a {@code
+     *                     null} value when querying for the mobile network type to receive usage
+     *                     for all mobile networks. For additional details see {@link
+     *                     TelephonyManager#getSubscriberId()}.
+     *                     <p>Starting with API level 31, calling apps can provide a
+     *                     {@code subscriberId} with wifi network type to receive usage for
+     *                     wifi networks which is under the given subscription if applicable.
+     *                     Otherwise, pass {@code null} when querying all wifi networks.
+     * @param startTime Start of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @return Bucket object or null if permissions are insufficient or error happened during
+     *         statistics collection.
+     */
+    @WorkerThread
+    public Bucket querySummaryForDevice(int networkType, String subscriberId,
+            long startTime, long endTime) throws SecurityException, RemoteException {
+        NetworkTemplate template;
+        try {
+            template = createTemplate(networkType, subscriberId);
+        } catch (IllegalArgumentException e) {
+            if (DBG) Log.e(TAG, "Cannot create template", e);
+            return null;
+        }
+
+        return querySummaryForDevice(template, startTime, endTime);
+    }
+
+    /**
+     * Query network usage statistics summaries. Result is summarised data usage for all uids
+     * belonging to calling user. Result is a single Bucket aggregated over time, state and uid.
+     * This means the bucket's start and end timestamp are going to be the same as the 'startTime'
+     * and 'endTime' parameters. State is going to be {@link NetworkStats.Bucket#STATE_ALL},
+     * uid {@link NetworkStats.Bucket#UID_ALL}, tag {@link NetworkStats.Bucket#TAG_NONE},
+     * metered {@link NetworkStats.Bucket#METERED_ALL}, and roaming
+     * {@link NetworkStats.Bucket#ROAMING_ALL}.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param networkType As defined in {@link ConnectivityManager}, e.g.
+     *            {@link ConnectivityManager#TYPE_MOBILE}, {@link ConnectivityManager#TYPE_WIFI}
+     *            etc.
+     * @param subscriberId If applicable, the subscriber id of the network interface.
+     *                     <p>Starting with API level 29, the {@code subscriberId} is guarded by
+     *                     additional restrictions. Calling apps that do not meet the new
+     *                     requirements to access the {@code subscriberId} can provide a {@code
+     *                     null} value when querying for the mobile network type to receive usage
+     *                     for all mobile networks. For additional details see {@link
+     *                     TelephonyManager#getSubscriberId()}.
+     *                     <p>Starting with API level 31, calling apps can provide a
+     *                     {@code subscriberId} with wifi network type to receive usage for
+     *                     wifi networks which is under the given subscription if applicable.
+     *                     Otherwise, pass {@code null} when querying all wifi networks.
+     * @param startTime Start of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @return Bucket object or null if permissions are insufficient or error happened during
+     *         statistics collection.
+     */
+    @WorkerThread
+    public Bucket querySummaryForUser(int networkType, String subscriberId, long startTime,
+            long endTime) throws SecurityException, RemoteException {
+        NetworkTemplate template;
+        try {
+            template = createTemplate(networkType, subscriberId);
+        } catch (IllegalArgumentException e) {
+            if (DBG) Log.e(TAG, "Cannot create template", e);
+            return null;
+        }
+
+        NetworkStats stats;
+        stats = new NetworkStats(mContext, template, mFlags, startTime, endTime, mService);
+        stats.startSummaryEnumeration();
+
+        stats.close();
+        return stats.getSummaryAggregate();
+    }
+
+    /**
+     * Query network usage statistics summaries. Result filtered to include only uids belonging to
+     * calling user. Result is aggregated over time, hence all buckets will have the same start and
+     * end timestamps. Not aggregated over state, uid, default network, metered, or roaming. This
+     * means buckets' start and end timestamps are going to be the same as the 'startTime' and
+     * 'endTime' parameters. State, uid, metered, and roaming are going to vary, and tag is going to
+     * be the same.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param networkType As defined in {@link ConnectivityManager}, e.g.
+     *            {@link ConnectivityManager#TYPE_MOBILE}, {@link ConnectivityManager#TYPE_WIFI}
+     *            etc.
+     * @param subscriberId If applicable, the subscriber id of the network interface.
+     *                     <p>Starting with API level 29, the {@code subscriberId} is guarded by
+     *                     additional restrictions. Calling apps that do not meet the new
+     *                     requirements to access the {@code subscriberId} can provide a {@code
+     *                     null} value when querying for the mobile network type to receive usage
+     *                     for all mobile networks. For additional details see {@link
+     *                     TelephonyManager#getSubscriberId()}.
+     *                     <p>Starting with API level 31, calling apps can provide a
+     *                     {@code subscriberId} with wifi network type to receive usage for
+     *                     wifi networks which is under the given subscription if applicable.
+     *                     Otherwise, pass {@code null} when querying all wifi networks.
+     * @param startTime Start of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @return Statistics object or null if permissions are insufficient or error happened during
+     *         statistics collection.
+     */
+    @WorkerThread
+    public NetworkStats querySummary(int networkType, String subscriberId, long startTime,
+            long endTime) throws SecurityException, RemoteException {
+        NetworkTemplate template;
+        try {
+            template = createTemplate(networkType, subscriberId);
+        } catch (IllegalArgumentException e) {
+            if (DBG) Log.e(TAG, "Cannot create template", e);
+            return null;
+        }
+
+        return querySummary(template, startTime, endTime);
+    }
+
+    /** @hide */
+    public NetworkStats querySummary(NetworkTemplate template, long startTime,
+            long endTime) throws SecurityException, RemoteException {
+        NetworkStats result;
+        result = new NetworkStats(mContext, template, mFlags, startTime, endTime, mService);
+        result.startSummaryEnumeration();
+
+        return result;
+    }
+
+    /**
+     * Query network usage statistics details for a given uid.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @see #queryDetailsForUidTagState(int, String, long, long, int, int, int)
+     */
+    @WorkerThread
+    public NetworkStats queryDetailsForUid(int networkType, String subscriberId,
+            long startTime, long endTime, int uid) throws SecurityException {
+        return queryDetailsForUidTagState(networkType, subscriberId, startTime, endTime, uid,
+            NetworkStats.Bucket.TAG_NONE, NetworkStats.Bucket.STATE_ALL);
+    }
+
+    /** @hide */
+    public NetworkStats queryDetailsForUid(NetworkTemplate template,
+            long startTime, long endTime, int uid) throws SecurityException {
+        return queryDetailsForUidTagState(template, startTime, endTime, uid,
+                NetworkStats.Bucket.TAG_NONE, NetworkStats.Bucket.STATE_ALL);
+    }
+
+    /**
+     * Query network usage statistics details for a given uid and tag.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @see #queryDetailsForUidTagState(int, String, long, long, int, int, int)
+     */
+    @WorkerThread
+    public NetworkStats queryDetailsForUidTag(int networkType, String subscriberId,
+            long startTime, long endTime, int uid, int tag) throws SecurityException {
+        return queryDetailsForUidTagState(networkType, subscriberId, startTime, endTime, uid,
+            tag, NetworkStats.Bucket.STATE_ALL);
+    }
+
+    /**
+     * Query network usage statistics details for a given uid, tag, and state. Only usable for uids
+     * belonging to calling user. Result is not aggregated over time. This means buckets' start and
+     * end timestamps are going to be between 'startTime' and 'endTime' parameters. The uid is going
+     * to be the same as the 'uid' parameter, the tag the same as the 'tag' parameter, and the state
+     * the same as the 'state' parameter.
+     * defaultNetwork is going to be {@link NetworkStats.Bucket#DEFAULT_NETWORK_ALL},
+     * metered is going to be {@link NetworkStats.Bucket#METERED_ALL}, and
+     * roaming is going to be {@link NetworkStats.Bucket#ROAMING_ALL}.
+     * <p>Only includes buckets that atomically occur in the inclusive time range. Doesn't
+     * interpolate across partial buckets. Since bucket length is in the order of hours, this
+     * method cannot be used to measure data usage on a fine grained time scale.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param networkType As defined in {@link ConnectivityManager}, e.g.
+     *            {@link ConnectivityManager#TYPE_MOBILE}, {@link ConnectivityManager#TYPE_WIFI}
+     *            etc.
+     * @param subscriberId If applicable, the subscriber id of the network interface.
+     *                     <p>Starting with API level 29, the {@code subscriberId} is guarded by
+     *                     additional restrictions. Calling apps that do not meet the new
+     *                     requirements to access the {@code subscriberId} can provide a {@code
+     *                     null} value when querying for the mobile network type to receive usage
+     *                     for all mobile networks. For additional details see {@link
+     *                     TelephonyManager#getSubscriberId()}.
+     *                     <p>Starting with API level 31, calling apps can provide a
+     *                     {@code subscriberId} with wifi network type to receive usage for
+     *                     wifi networks which is under the given subscription if applicable.
+     *                     Otherwise, pass {@code null} when querying all wifi networks.
+     * @param startTime Start of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param uid UID of app
+     * @param tag TAG of interest. Use {@link NetworkStats.Bucket#TAG_NONE} for no tags.
+     * @param state state of interest. Use {@link NetworkStats.Bucket#STATE_ALL} to aggregate
+     *            traffic from all states.
+     * @return Statistics object or null if an error happened during statistics collection.
+     * @throws SecurityException if permissions are insufficient to read network statistics.
+     */
+    @WorkerThread
+    public NetworkStats queryDetailsForUidTagState(int networkType, String subscriberId,
+            long startTime, long endTime, int uid, int tag, int state) throws SecurityException {
+        NetworkTemplate template;
+        template = createTemplate(networkType, subscriberId);
+
+        return queryDetailsForUidTagState(template, startTime, endTime, uid, tag, state);
+    }
+
+    /** @hide */
+    public NetworkStats queryDetailsForUidTagState(NetworkTemplate template,
+            long startTime, long endTime, int uid, int tag, int state) throws SecurityException {
+
+        NetworkStats result;
+        try {
+            result = new NetworkStats(mContext, template, mFlags, startTime, endTime, mService);
+            result.startHistoryEnumeration(uid, tag, state);
+        } catch (RemoteException e) {
+            Log.e(TAG, "Error while querying stats for uid=" + uid + " tag=" + tag
+                    + " state=" + state, e);
+            return null;
+        }
+
+        return result;
+    }
+
+    /**
+     * Query network usage statistics details. Result filtered to include only uids belonging to
+     * calling user. Result is aggregated over state but not aggregated over time, uid, tag,
+     * metered, nor roaming. This means buckets' start and end timestamps are going to be between
+     * 'startTime' and 'endTime' parameters. State is going to be
+     * {@link NetworkStats.Bucket#STATE_ALL}, uid will vary,
+     * tag {@link NetworkStats.Bucket#TAG_NONE},
+     * default network is going to be {@link NetworkStats.Bucket#DEFAULT_NETWORK_ALL},
+     * metered is going to be {@link NetworkStats.Bucket#METERED_ALL},
+     * and roaming is going to be {@link NetworkStats.Bucket#ROAMING_ALL}.
+     * <p>Only includes buckets that atomically occur in the inclusive time range. Doesn't
+     * interpolate across partial buckets. Since bucket length is in the order of hours, this
+     * method cannot be used to measure data usage on a fine grained time scale.
+     * This may take a long time, and apps should avoid calling this on their main thread.
+     *
+     * @param networkType As defined in {@link ConnectivityManager}, e.g.
+     *            {@link ConnectivityManager#TYPE_MOBILE}, {@link ConnectivityManager#TYPE_WIFI}
+     *            etc.
+     * @param subscriberId If applicable, the subscriber id of the network interface.
+     *                     <p>Starting with API level 29, the {@code subscriberId} is guarded by
+     *                     additional restrictions. Calling apps that do not meet the new
+     *                     requirements to access the {@code subscriberId} can provide a {@code
+     *                     null} value when querying for the mobile network type to receive usage
+     *                     for all mobile networks. For additional details see {@link
+     *                     TelephonyManager#getSubscriberId()}.
+     *                     <p>Starting with API level 31, calling apps can provide a
+     *                     {@code subscriberId} with wifi network type to receive usage for
+     *                     wifi networks which is under the given subscription if applicable.
+     *                     Otherwise, pass {@code null} when querying all wifi networks.
+     * @param startTime Start of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @param endTime End of period. Defined in terms of "Unix time", see
+     *            {@link java.lang.System#currentTimeMillis}.
+     * @return Statistics object or null if permissions are insufficient or error happened during
+     *         statistics collection.
+     */
+    @WorkerThread
+    public NetworkStats queryDetails(int networkType, String subscriberId, long startTime,
+            long endTime) throws SecurityException, RemoteException {
+        NetworkTemplate template;
+        try {
+            template = createTemplate(networkType, subscriberId);
+        } catch (IllegalArgumentException e) {
+            if (DBG) Log.e(TAG, "Cannot create template", e);
+            return null;
+        }
+
+        NetworkStats result;
+        result = new NetworkStats(mContext, template, mFlags, startTime, endTime, mService);
+        result.startUserUidEnumeration();
+        return result;
+    }
+
+    /** @hide */
+    public void registerUsageCallback(NetworkTemplate template, int networkType,
+            long thresholdBytes, UsageCallback callback, @Nullable Handler handler) {
+        Objects.requireNonNull(callback, "UsageCallback cannot be null");
+
+        final Looper looper;
+        if (handler == null) {
+            looper = Looper.myLooper();
+        } else {
+            looper = handler.getLooper();
+        }
+
+        DataUsageRequest request = new DataUsageRequest(DataUsageRequest.REQUEST_ID_UNSET,
+                template, thresholdBytes);
+        try {
+            CallbackHandler callbackHandler = new CallbackHandler(looper, networkType,
+                    template.getSubscriberId(), callback);
+            callback.request = mService.registerUsageCallback(
+                    mContext.getOpPackageName(), request, new Messenger(callbackHandler),
+                    new Binder());
+            if (DBG) Log.d(TAG, "registerUsageCallback returned " + callback.request);
+
+            if (callback.request == null) {
+                Log.e(TAG, "Request from callback is null; should not happen");
+            }
+        } catch (RemoteException e) {
+            if (DBG) Log.d(TAG, "Remote exception when registering callback");
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Registers to receive notifications about data usage on specified networks.
+     *
+     * @see #registerUsageCallback(int, String, long, UsageCallback, Handler)
+     */
+    public void registerUsageCallback(int networkType, String subscriberId, long thresholdBytes,
+            UsageCallback callback) {
+        registerUsageCallback(networkType, subscriberId, thresholdBytes, callback,
+                null /* handler */);
+    }
+
+    /**
+     * Registers to receive notifications about data usage on specified networks.
+     *
+     * <p>The callbacks will continue to be called as long as the process is live or
+     * {@link #unregisterUsageCallback} is called.
+     *
+     * @param networkType Type of network to monitor. Either
+                  {@link ConnectivityManager#TYPE_MOBILE} or {@link ConnectivityManager#TYPE_WIFI}.
+     * @param subscriberId If applicable, the subscriber id of the network interface.
+     *                     <p>Starting with API level 29, the {@code subscriberId} is guarded by
+     *                     additional restrictions. Calling apps that do not meet the new
+     *                     requirements to access the {@code subscriberId} can provide a {@code
+     *                     null} value when registering for the mobile network type to receive
+     *                     notifications for all mobile networks. For additional details see {@link
+     *                     TelephonyManager#getSubscriberId()}.
+     *                     <p>Starting with API level 31, calling apps can provide a
+     *                     {@code subscriberId} with wifi network type to receive usage for
+     *                     wifi networks which is under the given subscription if applicable.
+     *                     Otherwise, pass {@code null} when querying all wifi networks.
+     * @param thresholdBytes Threshold in bytes to be notified on.
+     * @param callback The {@link UsageCallback} that the system will call when data usage
+     *            has exceeded the specified threshold.
+     * @param handler to dispatch callback events through, otherwise if {@code null} it uses
+     *            the calling thread.
+     */
+    public void registerUsageCallback(int networkType, String subscriberId, long thresholdBytes,
+            UsageCallback callback, @Nullable Handler handler) {
+        NetworkTemplate template = createTemplate(networkType, subscriberId);
+        if (DBG) {
+            Log.d(TAG, "registerUsageCallback called with: {"
+                + " networkType=" + networkType
+                + " subscriberId=" + subscriberId
+                + " thresholdBytes=" + thresholdBytes
+                + " }");
+        }
+        registerUsageCallback(template, networkType, thresholdBytes, callback, handler);
+    }
+
+    /**
+     * Unregisters callbacks on data usage.
+     *
+     * @param callback The {@link UsageCallback} used when registering.
+     */
+    public void unregisterUsageCallback(UsageCallback callback) {
+        if (callback == null || callback.request == null
+                || callback.request.requestId == DataUsageRequest.REQUEST_ID_UNSET) {
+            throw new IllegalArgumentException("Invalid UsageCallback");
+        }
+        try {
+            mService.unregisterUsageRequest(callback.request);
+        } catch (RemoteException e) {
+            if (DBG) Log.d(TAG, "Remote exception when unregistering callback");
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Base class for usage callbacks. Should be extended by applications wanting notifications.
+     */
+    public static abstract class UsageCallback {
+
+        /**
+         * Called when data usage has reached the given threshold.
+         */
+        public abstract void onThresholdReached(int networkType, String subscriberId);
+
+        /**
+         * @hide used for internal bookkeeping
+         */
+        private DataUsageRequest request;
+    }
+
+    /**
+     * Registers a custom provider of {@link android.net.NetworkStats} to provide network statistics
+     * to the system. To unregister, invoke {@link #unregisterNetworkStatsProvider}.
+     * Note that no de-duplication of statistics between providers is performed, so each provider
+     * must only report network traffic that is not being reported by any other provider. Also note
+     * that the provider cannot be re-registered after unregistering.
+     *
+     * @param tag a human readable identifier of the custom network stats provider. This is only
+     *            used for debugging.
+     * @param provider the subclass of {@link NetworkStatsProvider} that needs to be
+     *                 registered to the system.
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(anyOf = {
+            android.Manifest.permission.NETWORK_STATS_PROVIDER,
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK})
+    @NonNull public void registerNetworkStatsProvider(
+            @NonNull String tag,
+            @NonNull NetworkStatsProvider provider) {
+        try {
+            if (provider.getProviderCallbackBinder() != null) {
+                throw new IllegalArgumentException("provider is already registered");
+            }
+            final INetworkStatsProviderCallback cbBinder =
+                    mService.registerNetworkStatsProvider(tag, provider.getProviderBinder());
+            provider.setProviderCallbackBinder(cbBinder);
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Unregisters an instance of {@link NetworkStatsProvider}.
+     *
+     * @param provider the subclass of {@link NetworkStatsProvider} that needs to be
+     *                 unregistered to the system.
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(anyOf = {
+            android.Manifest.permission.NETWORK_STATS_PROVIDER,
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK})
+    @NonNull public void unregisterNetworkStatsProvider(@NonNull NetworkStatsProvider provider) {
+        try {
+            provider.getProviderCallbackBinderOrThrow().unregister();
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    private static NetworkTemplate createTemplate(int networkType, String subscriberId) {
+        final NetworkTemplate template;
+        switch (networkType) {
+            case ConnectivityManager.TYPE_MOBILE:
+                template = subscriberId == null
+                        ? NetworkTemplate.buildTemplateMobileWildcard()
+                        : NetworkTemplate.buildTemplateMobileAll(subscriberId);
+                break;
+            case ConnectivityManager.TYPE_WIFI:
+                template = TextUtils.isEmpty(subscriberId)
+                        ? NetworkTemplate.buildTemplateWifiWildcard()
+                        : NetworkTemplate.buildTemplateWifi(NetworkTemplate.WIFI_NETWORKID_ALL,
+                                subscriberId);
+                break;
+            default:
+                throw new IllegalArgumentException("Cannot create template for network type "
+                        + networkType + ", subscriberId '"
+                        + NetworkIdentityUtils.scrubSubscriberId(subscriberId) + "'.");
+        }
+        return template;
+    }
+
+    /**
+     * Notify {@code NetworkStatsService} about network status changed.
+     *
+     * Notifies NetworkStatsService of network state changes for data usage accounting purposes.
+     *
+     * To avoid races that attribute data usage to wrong network, such as new network with
+     * the same interface after SIM hot-swap, this function will not return until
+     * {@code NetworkStatsService} finishes its work of retrieving traffic statistics from
+     * all data sources.
+     *
+     * @param defaultNetworks the list of all networks that could be used by network traffic that
+     *                        does not explicitly select a network.
+     * @param networkStateSnapshots a list of {@link NetworkStateSnapshot}s, one for
+     *                              each network that is currently connected.
+     * @param activeIface the active (i.e., connected) default network interface for the calling
+     *                    uid. Used to determine on which network future calls to
+     *                    {@link android.net.TrafficStats#incrementOperationCount} applies to.
+     * @param underlyingNetworkInfos the list of underlying network information for all
+     *                               currently-connected VPNs.
+     *
+     * @hide
+     */
+    @SystemApi(client = MODULE_LIBRARIES)
+    @RequiresPermission(anyOf = {
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
+            android.Manifest.permission.NETWORK_STACK})
+    public void notifyNetworkStatus(
+            @NonNull List<Network> defaultNetworks,
+            @NonNull List<NetworkStateSnapshot> networkStateSnapshots,
+            @Nullable String activeIface,
+            @NonNull List<UnderlyingNetworkInfo> underlyingNetworkInfos) {
+        try {
+            Objects.requireNonNull(defaultNetworks);
+            Objects.requireNonNull(networkStateSnapshots);
+            Objects.requireNonNull(underlyingNetworkInfos);
+            mService.notifyNetworkStatus(defaultNetworks.toArray(new Network[0]),
+                    networkStateSnapshots.toArray(new NetworkStateSnapshot[0]), activeIface,
+                    underlyingNetworkInfos.toArray(new UnderlyingNetworkInfo[0]));
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    private static class CallbackHandler extends Handler {
+        private final int mNetworkType;
+        private final String mSubscriberId;
+        private UsageCallback mCallback;
+
+        CallbackHandler(Looper looper, int networkType, String subscriberId,
+                UsageCallback callback) {
+            super(looper);
+            mNetworkType = networkType;
+            mSubscriberId = subscriberId;
+            mCallback = callback;
+        }
+
+        @Override
+        public void handleMessage(Message message) {
+            DataUsageRequest request =
+                    (DataUsageRequest) getObject(message, DataUsageRequest.PARCELABLE_KEY);
+
+            switch (message.what) {
+                case CALLBACK_LIMIT_REACHED: {
+                    if (mCallback != null) {
+                        mCallback.onThresholdReached(mNetworkType, mSubscriberId);
+                    } else {
+                        Log.e(TAG, "limit reached with released callback for " + request);
+                    }
+                    break;
+                }
+                case CALLBACK_RELEASED: {
+                    if (DBG) Log.d(TAG, "callback released for " + request);
+                    mCallback = null;
+                    break;
+                }
+            }
+        }
+
+        private static Object getObject(Message msg, String key) {
+            return msg.getData().getParcelable(key);
+        }
+    }
+}
diff --git a/framework-t/src/android/net/DataUsageRequest.aidl b/framework-t/src/android/net/DataUsageRequest.aidl
new file mode 100644
index 0000000..d1937c7
--- /dev/null
+++ b/framework-t/src/android/net/DataUsageRequest.aidl
@@ -0,0 +1,19 @@
+/**
+ * Copyright (c) 2016, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+parcelable DataUsageRequest;
diff --git a/framework-t/src/android/net/DataUsageRequest.java b/framework-t/src/android/net/DataUsageRequest.java
new file mode 100644
index 0000000..b06d515
--- /dev/null
+++ b/framework-t/src/android/net/DataUsageRequest.java
@@ -0,0 +1,112 @@
+/**
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy
+ * of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+
+package android.net;
+
+import android.annotation.Nullable;
+import android.net.NetworkTemplate;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import java.util.Objects;
+
+/**
+ * Defines a request to register a callbacks. Used to be notified on data usage via
+ * {@link android.app.usage.NetworkStatsManager#registerDataUsageCallback}.
+ * If no {@code uid}s are set, callbacks are restricted to device-owners,
+ * carrier-privileged apps, or system apps.
+ *
+ * @hide
+ */
+public final class DataUsageRequest implements Parcelable {
+
+    public static final String PARCELABLE_KEY = "DataUsageRequest";
+    public static final int REQUEST_ID_UNSET = 0;
+
+    /**
+     * Identifies the request.  {@link DataUsageRequest}s should only be constructed by
+     * the Framework and it is used internally to identify the request.
+     */
+    public final int requestId;
+
+    /**
+     * {@link NetworkTemplate} describing the network to monitor.
+     */
+    public final NetworkTemplate template;
+
+    /**
+     * Threshold in bytes to be notified on.
+     */
+    public final long thresholdInBytes;
+
+    public DataUsageRequest(int requestId, NetworkTemplate template, long thresholdInBytes) {
+        this.requestId = requestId;
+        this.template = template;
+        this.thresholdInBytes = thresholdInBytes;
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel dest, int flags) {
+        dest.writeInt(requestId);
+        dest.writeParcelable(template, flags);
+        dest.writeLong(thresholdInBytes);
+    }
+
+    public static final @android.annotation.NonNull Creator<DataUsageRequest> CREATOR =
+            new Creator<DataUsageRequest>() {
+                @Override
+                public DataUsageRequest createFromParcel(Parcel in) {
+                    int requestId = in.readInt();
+                    NetworkTemplate template = in.readParcelable(null);
+                    long thresholdInBytes = in.readLong();
+                    DataUsageRequest result = new DataUsageRequest(requestId, template,
+                            thresholdInBytes);
+                    return result;
+                }
+
+                @Override
+                public DataUsageRequest[] newArray(int size) {
+                    return new DataUsageRequest[size];
+                }
+            };
+
+    @Override
+    public String toString() {
+        return "DataUsageRequest [ requestId=" + requestId
+                + ", networkTemplate=" + template
+                + ", thresholdInBytes=" + thresholdInBytes + " ]";
+    }
+
+    @Override
+    public boolean equals(@Nullable Object obj) {
+        if (obj instanceof DataUsageRequest == false) return false;
+        DataUsageRequest that = (DataUsageRequest) obj;
+        return that.requestId == this.requestId
+                && Objects.equals(that.template, this.template)
+                && that.thresholdInBytes == this.thresholdInBytes;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(requestId, template, thresholdInBytes);
+   }
+
+}
diff --git a/framework-t/src/android/net/INetworkStatsService.aidl b/framework-t/src/android/net/INetworkStatsService.aidl
new file mode 100644
index 0000000..12937b5
--- /dev/null
+++ b/framework-t/src/android/net/INetworkStatsService.aidl
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.net.DataUsageRequest;
+import android.net.INetworkStatsSession;
+import android.net.Network;
+import android.net.NetworkStateSnapshot;
+import android.net.NetworkStats;
+import android.net.NetworkStatsHistory;
+import android.net.NetworkTemplate;
+import android.net.UnderlyingNetworkInfo;
+import android.net.netstats.provider.INetworkStatsProvider;
+import android.net.netstats.provider.INetworkStatsProviderCallback;
+import android.os.IBinder;
+import android.os.Messenger;
+
+/** {@hide} */
+interface INetworkStatsService {
+
+    /** Start a statistics query session. */
+    @UnsupportedAppUsage
+    INetworkStatsSession openSession();
+
+    /** Start a statistics query session. If calling package is profile or device owner then it is
+     *  granted automatic access if apiLevel is NetworkStatsManager.API_LEVEL_DPC_ALLOWED. If
+     *  apiLevel is at least NetworkStatsManager.API_LEVEL_REQUIRES_PACKAGE_USAGE_STATS then
+     *  PACKAGE_USAGE_STATS permission is always checked. If PACKAGE_USAGE_STATS is not granted
+     *  READ_NETWORK_USAGE_STATS is checked for.
+     */
+    @UnsupportedAppUsage(maxTargetSdk = 30, trackingBug = 170729553)
+    INetworkStatsSession openSessionForUsageStats(int flags, String callingPackage);
+
+    /** Return data layer snapshot of UID network usage. */
+    @UnsupportedAppUsage
+    NetworkStats getDataLayerSnapshotForUid(int uid);
+
+    /** Get a detailed snapshot of stats since boot for all UIDs.
+    *
+    * <p>Results will not always be limited to stats on requiredIfaces when specified: stats for
+    * interfaces stacked on the specified interfaces, or for interfaces on which the specified
+    * interfaces are stacked on, will also be included.
+    * @param requiredIfaces Interface names to get data for, or {@link NetworkStats#INTERFACES_ALL}.
+    */
+    NetworkStats getDetailedUidStats(in String[] requiredIfaces);
+
+    /** Return set of any ifaces associated with mobile networks since boot. */
+    @UnsupportedAppUsage
+    String[] getMobileIfaces();
+
+    /** Increment data layer count of operations performed for UID and tag. */
+    void incrementOperationCount(int uid, int tag, int operationCount);
+
+    /**  Notify {@code NetworkStatsService} about network status changed. */
+    void notifyNetworkStatus(
+         in Network[] defaultNetworks,
+         in NetworkStateSnapshot[] snapshots,
+         in String activeIface,
+         in UnderlyingNetworkInfo[] underlyingNetworkInfos);
+    /** Force update of statistics. */
+    @UnsupportedAppUsage
+    void forceUpdate();
+
+    /** Registers a callback on data usage. */
+    DataUsageRequest registerUsageCallback(String callingPackage,
+            in DataUsageRequest request, in Messenger messenger, in IBinder binder);
+
+    /** Unregisters a callback on data usage. */
+    void unregisterUsageRequest(in DataUsageRequest request);
+
+    /** Get the uid stats information since boot */
+    long getUidStats(int uid, int type);
+
+    /** Get the iface stats information since boot */
+    long getIfaceStats(String iface, int type);
+
+    /** Get the total network stats information since boot */
+    long getTotalStats(int type);
+
+    /** Registers a network stats provider */
+    INetworkStatsProviderCallback registerNetworkStatsProvider(String tag,
+            in INetworkStatsProvider provider);
+}
diff --git a/framework-t/src/android/net/INetworkStatsSession.aidl b/framework-t/src/android/net/INetworkStatsSession.aidl
new file mode 100644
index 0000000..dfedf66
--- /dev/null
+++ b/framework-t/src/android/net/INetworkStatsSession.aidl
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.net.NetworkStats;
+import android.net.NetworkStatsHistory;
+import android.net.NetworkTemplate;
+
+/** {@hide} */
+interface INetworkStatsSession {
+
+    /** Return device aggregated network layer usage summary for traffic that matches template. */
+    NetworkStats getDeviceSummaryForNetwork(in NetworkTemplate template, long start, long end);
+
+    /** Return network layer usage summary for traffic that matches template. */
+    @UnsupportedAppUsage
+    NetworkStats getSummaryForNetwork(in NetworkTemplate template, long start, long end);
+    /** Return historical network layer stats for traffic that matches template. */
+    @UnsupportedAppUsage
+    NetworkStatsHistory getHistoryForNetwork(in NetworkTemplate template, int fields);
+
+    /**
+     * Return network layer usage summary per UID for traffic that matches template.
+     *
+     * <p>The resulting {@code NetworkStats#getElapsedRealtime()} contains time delta between
+     * {@code start} and {@code end}.
+     *
+     * @param template - a predicate to filter netstats.
+     * @param start - start of the range, timestamp in milliseconds since the epoch.
+     * @param end - end of the range, timestamp in milliseconds since the epoch.
+     * @param includeTags - includes data usage tags if true.
+     */
+    @UnsupportedAppUsage
+    NetworkStats getSummaryForAllUid(in NetworkTemplate template, long start, long end, boolean includeTags);
+    /** Return historical network layer stats for specific UID traffic that matches template. */
+    @UnsupportedAppUsage
+    NetworkStatsHistory getHistoryForUid(in NetworkTemplate template, int uid, int set, int tag, int fields);
+    /** Return historical network layer stats for specific UID traffic that matches template. */
+    NetworkStatsHistory getHistoryIntervalForUid(in NetworkTemplate template, int uid, int set, int tag, int fields, long start, long end);
+
+    /** Return array of uids that have stats and are accessible to the calling user */
+    int[] getRelevantUids();
+
+    @UnsupportedAppUsage
+    void close();
+
+}
diff --git a/framework-t/src/android/net/NetworkIdentity.java b/framework-t/src/android/net/NetworkIdentity.java
new file mode 100644
index 0000000..eb8f43e
--- /dev/null
+++ b/framework-t/src/android/net/NetworkIdentity.java
@@ -0,0 +1,286 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.net.ConnectivityManager.TYPE_WIFI;
+
+import android.annotation.Nullable;
+import android.content.Context;
+import android.net.wifi.WifiInfo;
+import android.net.wifi.WifiManager;
+import android.service.NetworkIdentityProto;
+import android.telephony.Annotation.NetworkType;
+import android.util.proto.ProtoOutputStream;
+
+import com.android.net.module.util.NetworkCapabilitiesUtils;
+import com.android.net.module.util.NetworkIdentityUtils;
+
+import java.util.ArrayList;
+import java.util.Objects;
+
+/**
+ * Network definition that includes strong identity. Analogous to combining
+ * {@link NetworkCapabilities} and an IMSI.
+ *
+ * @hide
+ */
+public class NetworkIdentity implements Comparable<NetworkIdentity> {
+    private static final String TAG = "NetworkIdentity";
+
+    public static final int SUBTYPE_COMBINED = -1;
+
+    /**
+     * Network has no {@code NetworkCapabilities#NET_CAPABILITY_OEM_*}.
+     * @hide
+     */
+    public static final int OEM_NONE = 0x0;
+    /**
+     * Network has {@link NetworkCapabilities#NET_CAPABILITY_OEM_PAID}.
+     * @hide
+     */
+    public static final int OEM_PAID = 0x1;
+    /**
+     * Network has {@link NetworkCapabilities#NET_CAPABILITY_OEM_PRIVATE}.
+     * @hide
+     */
+    public static final int OEM_PRIVATE = 0x2;
+
+    final int mType;
+    final int mSubType;
+    final String mSubscriberId;
+    final String mNetworkId;
+    final boolean mRoaming;
+    final boolean mMetered;
+    final boolean mDefaultNetwork;
+    final int mOemManaged;
+
+    public NetworkIdentity(
+            int type, int subType, String subscriberId, String networkId, boolean roaming,
+            boolean metered, boolean defaultNetwork, int oemManaged) {
+        mType = type;
+        mSubType = subType;
+        mSubscriberId = subscriberId;
+        mNetworkId = networkId;
+        mRoaming = roaming;
+        mMetered = metered;
+        mDefaultNetwork = defaultNetwork;
+        mOemManaged = oemManaged;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mType, mSubType, mSubscriberId, mNetworkId, mRoaming, mMetered,
+                mDefaultNetwork, mOemManaged);
+    }
+
+    @Override
+    public boolean equals(@Nullable Object obj) {
+        if (obj instanceof NetworkIdentity) {
+            final NetworkIdentity ident = (NetworkIdentity) obj;
+            return mType == ident.mType && mSubType == ident.mSubType && mRoaming == ident.mRoaming
+                    && Objects.equals(mSubscriberId, ident.mSubscriberId)
+                    && Objects.equals(mNetworkId, ident.mNetworkId)
+                    && mMetered == ident.mMetered
+                    && mDefaultNetwork == ident.mDefaultNetwork
+                    && mOemManaged == ident.mOemManaged;
+        }
+        return false;
+    }
+
+    @Override
+    public String toString() {
+        final StringBuilder builder = new StringBuilder("{");
+        builder.append("type=").append(mType);
+        builder.append(", subType=");
+        if (mSubType == SUBTYPE_COMBINED) {
+            builder.append("COMBINED");
+        } else {
+            builder.append(mSubType);
+        }
+        if (mSubscriberId != null) {
+            builder.append(", subscriberId=")
+                    .append(NetworkIdentityUtils.scrubSubscriberId(mSubscriberId));
+        }
+        if (mNetworkId != null) {
+            builder.append(", networkId=").append(mNetworkId);
+        }
+        if (mRoaming) {
+            builder.append(", ROAMING");
+        }
+        builder.append(", metered=").append(mMetered);
+        builder.append(", defaultNetwork=").append(mDefaultNetwork);
+        builder.append(", oemManaged=").append(getOemManagedNames(mOemManaged));
+        return builder.append("}").toString();
+    }
+
+    /**
+     * Get the human readable representation of a bitfield representing the OEM managed state of a
+     * network.
+     */
+    static String getOemManagedNames(int oemManaged) {
+        if (oemManaged == OEM_NONE) {
+            return "OEM_NONE";
+        }
+        final int[] bitPositions = NetworkCapabilitiesUtils.unpackBits(oemManaged);
+        final ArrayList<String> oemManagedNames = new ArrayList<String>();
+        for (int position : bitPositions) {
+            oemManagedNames.add(nameOfOemManaged(1 << position));
+        }
+        return String.join(",", oemManagedNames);
+    }
+
+    private static String nameOfOemManaged(int oemManagedBit) {
+        switch (oemManagedBit) {
+            case OEM_PAID:
+                return "OEM_PAID";
+            case OEM_PRIVATE:
+                return "OEM_PRIVATE";
+            default:
+                return "Invalid(" + oemManagedBit + ")";
+        }
+    }
+
+    public void dumpDebug(ProtoOutputStream proto, long tag) {
+        final long start = proto.start(tag);
+
+        proto.write(NetworkIdentityProto.TYPE, mType);
+
+        // Not dumping mSubType, subtypes are no longer supported.
+
+        if (mSubscriberId != null) {
+            proto.write(NetworkIdentityProto.SUBSCRIBER_ID,
+                    NetworkIdentityUtils.scrubSubscriberId(mSubscriberId));
+        }
+        proto.write(NetworkIdentityProto.NETWORK_ID, mNetworkId);
+        proto.write(NetworkIdentityProto.ROAMING, mRoaming);
+        proto.write(NetworkIdentityProto.METERED, mMetered);
+        proto.write(NetworkIdentityProto.DEFAULT_NETWORK, mDefaultNetwork);
+        proto.write(NetworkIdentityProto.OEM_MANAGED_NETWORK, mOemManaged);
+
+        proto.end(start);
+    }
+
+    public int getType() {
+        return mType;
+    }
+
+    public int getSubType() {
+        return mSubType;
+    }
+
+    public String getSubscriberId() {
+        return mSubscriberId;
+    }
+
+    public String getNetworkId() {
+        return mNetworkId;
+    }
+
+    public boolean getRoaming() {
+        return mRoaming;
+    }
+
+    public boolean getMetered() {
+        return mMetered;
+    }
+
+    public boolean getDefaultNetwork() {
+        return mDefaultNetwork;
+    }
+
+    public int getOemManaged() {
+        return mOemManaged;
+    }
+
+    /**
+     * Build a {@link NetworkIdentity} from the given {@link NetworkStateSnapshot} and
+     * {@code subType}, assuming that any mobile networks are using the current IMSI.
+     * The subType if applicable, should be set as one of the TelephonyManager.NETWORK_TYPE_*
+     * constants, or {@link android.telephony.TelephonyManager#NETWORK_TYPE_UNKNOWN} if not.
+     */
+    public static NetworkIdentity buildNetworkIdentity(Context context,
+            NetworkStateSnapshot snapshot, boolean defaultNetwork, @NetworkType int subType) {
+        final int legacyType = snapshot.getLegacyType();
+
+        final String subscriberId = snapshot.getSubscriberId();
+        String networkId = null;
+        boolean roaming = !snapshot.getNetworkCapabilities().hasCapability(
+                NetworkCapabilities.NET_CAPABILITY_NOT_ROAMING);
+        boolean metered = !(snapshot.getNetworkCapabilities().hasCapability(
+                NetworkCapabilities.NET_CAPABILITY_NOT_METERED)
+                || snapshot.getNetworkCapabilities().hasCapability(
+                NetworkCapabilities.NET_CAPABILITY_TEMPORARILY_NOT_METERED));
+
+        final int oemManaged = getOemBitfield(snapshot.getNetworkCapabilities());
+
+        if (legacyType == TYPE_WIFI) {
+            networkId = snapshot.getNetworkCapabilities().getSsid();
+            if (networkId == null) {
+                final WifiManager wifi = context.getSystemService(WifiManager.class);
+                final WifiInfo info = wifi.getConnectionInfo();
+                networkId = info != null ? info.getSSID() : null;
+            }
+        }
+
+        return new NetworkIdentity(legacyType, subType, subscriberId, networkId, roaming, metered,
+                defaultNetwork, oemManaged);
+    }
+
+    /**
+     * Builds a bitfield of {@code NetworkIdentity.OEM_*} based on {@link NetworkCapabilities}.
+     * @hide
+     */
+    public static int getOemBitfield(NetworkCapabilities nc) {
+        int oemManaged = OEM_NONE;
+
+        if (nc.hasCapability(NetworkCapabilities.NET_CAPABILITY_OEM_PAID)) {
+            oemManaged |= OEM_PAID;
+        }
+        if (nc.hasCapability(NetworkCapabilities.NET_CAPABILITY_OEM_PRIVATE)) {
+            oemManaged |= OEM_PRIVATE;
+        }
+
+        return oemManaged;
+    }
+
+    @Override
+    public int compareTo(NetworkIdentity another) {
+        int res = Integer.compare(mType, another.mType);
+        if (res == 0) {
+            res = Integer.compare(mSubType, another.mSubType);
+        }
+        if (res == 0 && mSubscriberId != null && another.mSubscriberId != null) {
+            res = mSubscriberId.compareTo(another.mSubscriberId);
+        }
+        if (res == 0 && mNetworkId != null && another.mNetworkId != null) {
+            res = mNetworkId.compareTo(another.mNetworkId);
+        }
+        if (res == 0) {
+            res = Boolean.compare(mRoaming, another.mRoaming);
+        }
+        if (res == 0) {
+            res = Boolean.compare(mMetered, another.mMetered);
+        }
+        if (res == 0) {
+            res = Boolean.compare(mDefaultNetwork, another.mDefaultNetwork);
+        }
+        if (res == 0) {
+            res = Integer.compare(mOemManaged, another.mOemManaged);
+        }
+        return res;
+    }
+}
diff --git a/framework-t/src/android/net/NetworkStateSnapshot.java b/framework-t/src/android/net/NetworkStateSnapshot.java
new file mode 100644
index 0000000..3915634
--- /dev/null
+++ b/framework-t/src/android/net/NetworkStateSnapshot.java
@@ -0,0 +1,173 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import com.android.net.module.util.NetworkIdentityUtils;
+
+import java.util.Objects;
+
+/**
+ * Snapshot of network state.
+ *
+ * @hide
+ */
+@SystemApi(client = MODULE_LIBRARIES)
+public final class NetworkStateSnapshot implements Parcelable {
+    /** The network associated with this snapshot. */
+    @NonNull
+    private final Network mNetwork;
+
+    /** The {@link NetworkCapabilities} of the network associated with this snapshot. */
+    @NonNull
+    private final NetworkCapabilities mNetworkCapabilities;
+
+    /** The {@link LinkProperties} of the network associated with this snapshot. */
+    @NonNull
+    private final LinkProperties mLinkProperties;
+
+    /**
+     * The Subscriber Id of the network associated with this snapshot. See
+     * {@link android.telephony.TelephonyManager#getSubscriberId()}.
+     */
+    @Nullable
+    private final String mSubscriberId;
+
+    /**
+     * The legacy type of the network associated with this snapshot. See
+     * {@code ConnectivityManager#TYPE_*}.
+     */
+    private final int mLegacyType;
+
+    public NetworkStateSnapshot(@NonNull Network network,
+            @NonNull NetworkCapabilities networkCapabilities,
+            @NonNull LinkProperties linkProperties,
+            @Nullable String subscriberId, int legacyType) {
+        mNetwork = Objects.requireNonNull(network);
+        mNetworkCapabilities = Objects.requireNonNull(networkCapabilities);
+        mLinkProperties = Objects.requireNonNull(linkProperties);
+        mSubscriberId = subscriberId;
+        mLegacyType = legacyType;
+    }
+
+    /** @hide */
+    public NetworkStateSnapshot(@NonNull Parcel in) {
+        mNetwork = in.readParcelable(null);
+        mNetworkCapabilities = in.readParcelable(null);
+        mLinkProperties = in.readParcelable(null);
+        mSubscriberId = in.readString();
+        mLegacyType = in.readInt();
+    }
+
+    /** Get the network associated with this snapshot */
+    @NonNull
+    public Network getNetwork() {
+        return mNetwork;
+    }
+
+    /** Get {@link NetworkCapabilities} of the network associated with this snapshot. */
+    @NonNull
+    public NetworkCapabilities getNetworkCapabilities() {
+        return mNetworkCapabilities;
+    }
+
+    /** Get the {@link LinkProperties} of the network associated with this snapshot. */
+    @NonNull
+    public LinkProperties getLinkProperties() {
+        return mLinkProperties;
+    }
+
+    /** Get the Subscriber Id of the network associated with this snapshot. */
+    @Nullable
+    public String getSubscriberId() {
+        return mSubscriberId;
+    }
+
+    /**
+     * Get the legacy type of the network associated with this snapshot.
+     * @return the legacy network type. See {@code ConnectivityManager#TYPE_*}.
+     */
+    public int getLegacyType() {
+        return mLegacyType;
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel out, int flags) {
+        out.writeParcelable(mNetwork, flags);
+        out.writeParcelable(mNetworkCapabilities, flags);
+        out.writeParcelable(mLinkProperties, flags);
+        out.writeString(mSubscriberId);
+        out.writeInt(mLegacyType);
+    }
+
+    @NonNull
+    public static final Creator<NetworkStateSnapshot> CREATOR =
+            new Creator<NetworkStateSnapshot>() {
+        @NonNull
+        @Override
+        public NetworkStateSnapshot createFromParcel(@NonNull Parcel in) {
+            return new NetworkStateSnapshot(in);
+        }
+
+        @NonNull
+        @Override
+        public NetworkStateSnapshot[] newArray(int size) {
+            return new NetworkStateSnapshot[size];
+        }
+    };
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (!(o instanceof NetworkStateSnapshot)) return false;
+        NetworkStateSnapshot that = (NetworkStateSnapshot) o;
+        return mLegacyType == that.mLegacyType
+                && Objects.equals(mNetwork, that.mNetwork)
+                && Objects.equals(mNetworkCapabilities, that.mNetworkCapabilities)
+                && Objects.equals(mLinkProperties, that.mLinkProperties)
+                && Objects.equals(mSubscriberId, that.mSubscriberId);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mNetwork,
+                mNetworkCapabilities, mLinkProperties, mSubscriberId, mLegacyType);
+    }
+
+    @Override
+    public String toString() {
+        return "NetworkStateSnapshot{"
+                + "network=" + mNetwork
+                + ", networkCapabilities=" + mNetworkCapabilities
+                + ", linkProperties=" + mLinkProperties
+                + ", subscriberId='" + NetworkIdentityUtils.scrubSubscriberId(mSubscriberId) + '\''
+                + ", legacyType=" + mLegacyType
+                + '}';
+    }
+}
diff --git a/framework-t/src/android/net/NetworkStats.java b/framework-t/src/android/net/NetworkStats.java
new file mode 100644
index 0000000..c7ffc19
--- /dev/null
+++ b/framework-t/src/android/net/NetworkStats.java
@@ -0,0 +1,1738 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static com.android.internal.net.NetworkUtilsInternal.multiplySafeByRational;
+
+import android.annotation.IntDef;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+import android.compat.annotation.UnsupportedAppUsage;
+import android.os.Build;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.os.Process;
+import android.os.SystemClock;
+import android.util.SparseBooleanArray;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.util.ArrayUtils;
+
+import libcore.util.EmptyArray;
+
+import java.io.CharArrayWriter;
+import java.io.PrintWriter;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.function.Predicate;
+
+/**
+ * Collection of active network statistics. Can contain summary details across
+ * all interfaces, or details with per-UID granularity. Internally stores data
+ * as a large table, closely matching {@code /proc/} data format. This structure
+ * optimizes for rapid in-memory comparison, but consider using
+ * {@link NetworkStatsHistory} when persisting.
+ *
+ * @hide
+ */
+// @NotThreadSafe
+@SystemApi
+public final class NetworkStats implements Parcelable {
+    private static final String TAG = "NetworkStats";
+
+    /**
+     * {@link #iface} value when interface details unavailable.
+     * @hide
+     */
+    @Nullable public static final String IFACE_ALL = null;
+
+    /**
+     * Virtual network interface for video telephony. This is for VT data usage counting
+     * purpose.
+     */
+    public static final String IFACE_VT = "vt_data0";
+
+    /** {@link #uid} value when UID details unavailable. */
+    public static final int UID_ALL = -1;
+    /** Special UID value for data usage by tethering. */
+    public static final int UID_TETHERING = -5;
+
+    /**
+     * {@link #tag} value matching any tag.
+     * @hide
+     */
+    // TODO: Rename TAG_ALL to TAG_ANY.
+    public static final int TAG_ALL = -1;
+    /**
+     * {@link #set} value for all sets combined, not including debug sets.
+     * @hide
+     */
+    public static final int SET_ALL = -1;
+    /** {@link #set} value where background data is accounted. */
+    public static final int SET_DEFAULT = 0;
+    /** {@link #set} value where foreground data is accounted. */
+    public static final int SET_FOREGROUND = 1;
+    /**
+     * All {@link #set} value greater than SET_DEBUG_START are debug {@link #set} values.
+     * @hide
+     */
+    public static final int SET_DEBUG_START = 1000;
+    /**
+     * Debug {@link #set} value when the VPN stats are moved in.
+     * @hide
+     */
+    public static final int SET_DBG_VPN_IN = 1001;
+    /**
+     * Debug {@link #set} value when the VPN stats are moved out of a vpn UID.
+     * @hide
+     */
+    public static final int SET_DBG_VPN_OUT = 1002;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "SET_" }, value = {
+            SET_ALL,
+            SET_DEFAULT,
+            SET_FOREGROUND,
+            SET_DEBUG_START,
+            SET_DBG_VPN_IN,
+            SET_DBG_VPN_OUT
+    })
+    public @interface State {
+    }
+
+    /**
+     * Include all interfaces when filtering
+     * @hide
+     */
+    public @Nullable static final String[] INTERFACES_ALL = null;
+
+    /** {@link #tag} value for total data across all tags. */
+    // TODO: Rename TAG_NONE to TAG_ALL.
+    public static final int TAG_NONE = 0;
+
+    /**
+     * {@link #metered} value to account for all metered states.
+     * @hide
+     */
+    public static final int METERED_ALL = -1;
+    /** {@link #metered} value where native, unmetered data is accounted. */
+    public static final int METERED_NO = 0;
+    /** {@link #metered} value where metered data is accounted. */
+    public static final int METERED_YES = 1;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "METERED_" }, value = {
+            METERED_ALL,
+            METERED_NO,
+            METERED_YES
+    })
+    public @interface Meteredness {
+    }
+
+
+    /**
+     * {@link #roaming} value to account for all roaming states.
+     * @hide
+     */
+    public static final int ROAMING_ALL = -1;
+    /** {@link #roaming} value where native, non-roaming data is accounted. */
+    public static final int ROAMING_NO = 0;
+    /** {@link #roaming} value where roaming data is accounted. */
+    public static final int ROAMING_YES = 1;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "ROAMING_" }, value = {
+            ROAMING_ALL,
+            ROAMING_NO,
+            ROAMING_YES
+    })
+    public @interface Roaming {
+    }
+
+    /**
+     * {@link #onDefaultNetwork} value to account for all default network states.
+     * @hide
+     */
+    public static final int DEFAULT_NETWORK_ALL = -1;
+    /** {@link #onDefaultNetwork} value to account for usage while not the default network. */
+    public static final int DEFAULT_NETWORK_NO = 0;
+    /** {@link #onDefaultNetwork} value to account for usage while the default network. */
+    public static final int DEFAULT_NETWORK_YES = 1;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "DEFAULT_NETWORK_" }, value = {
+            DEFAULT_NETWORK_ALL,
+            DEFAULT_NETWORK_NO,
+            DEFAULT_NETWORK_YES
+    })
+    public @interface DefaultNetwork {
+    }
+
+    /**
+     * Denotes a request for stats at the interface level.
+     * @hide
+     */
+    public static final int STATS_PER_IFACE = 0;
+    /**
+     * Denotes a request for stats at the interface and UID level.
+     * @hide
+     */
+    public static final int STATS_PER_UID = 1;
+
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(prefix = { "STATS_PER_" }, value = {
+            STATS_PER_IFACE,
+            STATS_PER_UID
+    })
+    public @interface StatsType {
+    }
+
+    private static final String CLATD_INTERFACE_PREFIX = "v4-";
+    // Delta between IPv4 header (20b) and IPv6 header (40b).
+    // Used for correct stats accounting on clatd interfaces.
+    private static final int IPV4V6_HEADER_DELTA = 20;
+
+    // TODO: move fields to "mVariable" notation
+
+    /**
+     * {@link SystemClock#elapsedRealtime()} timestamp in milliseconds when this data was
+     * generated.
+     * It's a timestamps delta when {@link #subtract()},
+     * {@code INetworkStatsSession#getSummaryForAllUid()} methods are used.
+     */
+    private long elapsedRealtime;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private int size;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private int capacity;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private String[] iface;
+    @UnsupportedAppUsage
+    private int[] uid;
+    @UnsupportedAppUsage
+    private int[] set;
+    @UnsupportedAppUsage
+    private int[] tag;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private int[] metered;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private int[] roaming;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private int[] defaultNetwork;
+    @UnsupportedAppUsage
+    private long[] rxBytes;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private long[] rxPackets;
+    @UnsupportedAppUsage
+    private long[] txBytes;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private long[] txPackets;
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    private long[] operations;
+
+    /**
+     * Basic element of network statistics. Contains the number of packets and number of bytes
+     * transferred on both directions in a given set of conditions. See
+     * {@link Entry#Entry(String, int, int, int, int, int, int, long, long, long, long, long)}.
+     *
+     * @hide
+     */
+    @SystemApi
+    public static class Entry {
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public String iface;
+        /** @hide */
+        @UnsupportedAppUsage
+        public int uid;
+        /** @hide */
+        @UnsupportedAppUsage
+        public int set;
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public int tag;
+        /**
+         * Note that this is only populated w/ the default value when read from /proc or written
+         * to disk. We merge in the correct value when reporting this value to clients of
+         * getSummary().
+         * @hide
+         */
+        public int metered;
+        /**
+         * Note that this is only populated w/ the default value when read from /proc or written
+         * to disk. We merge in the correct value when reporting this value to clients of
+         * getSummary().
+         * @hide
+         */
+        public int roaming;
+        /**
+         * Note that this is only populated w/ the default value when read from /proc or written
+         * to disk. We merge in the correct value when reporting this value to clients of
+         * getSummary().
+         * @hide
+         */
+        public int defaultNetwork;
+        /** @hide */
+        @UnsupportedAppUsage
+        public long rxBytes;
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long rxPackets;
+        /** @hide */
+        @UnsupportedAppUsage
+        public long txBytes;
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long txPackets;
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long operations;
+
+        /** @hide */
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public Entry() {
+            this(IFACE_ALL, UID_ALL, SET_DEFAULT, TAG_NONE, 0L, 0L, 0L, 0L, 0L);
+        }
+
+        /** @hide */
+        public Entry(long rxBytes, long rxPackets, long txBytes, long txPackets, long operations) {
+            this(IFACE_ALL, UID_ALL, SET_DEFAULT, TAG_NONE, rxBytes, rxPackets, txBytes, txPackets,
+                    operations);
+        }
+
+        /** @hide */
+        public Entry(String iface, int uid, int set, int tag, long rxBytes, long rxPackets,
+                long txBytes, long txPackets, long operations) {
+            this(iface, uid, set, tag, METERED_NO, ROAMING_NO, DEFAULT_NETWORK_NO,
+                    rxBytes, rxPackets, txBytes, txPackets, operations);
+        }
+
+        /**
+         * Construct a {@link Entry} object by giving statistics of packet and byte transferred on
+         * both direction, and associated with a set of given conditions.
+         *
+         * @param iface interface name of this {@link Entry}. Or null if not specified.
+         * @param uid uid of this {@link Entry}. {@link #UID_TETHERING} if this {@link Entry} is
+         *            for tethering. Or {@link #UID_ALL} if this {@link NetworkStats} is only
+         *            counting iface stats.
+         * @param set usage state of this {@link Entry}. Should be one of the following
+         *            values: {@link #SET_DEFAULT}, {@link #SET_FOREGROUND}.
+         * @param tag tag of this {@link Entry}.
+         * @param metered metered state of this {@link Entry}. Should be one of the following
+         *                values: {link #METERED_YES}, {link #METERED_NO}.
+         * @param roaming roaming state of this {@link Entry}. Should be one of the following
+         *                values: {link #ROAMING_YES}, {link #ROAMING_NO}.
+         * @param defaultNetwork default network status of this {@link Entry}. Should be one
+         *                       of the following values: {link #DEFAULT_NETWORK_YES},
+         *                       {link #DEFAULT_NETWORK_NO}.
+         * @param rxBytes Number of bytes received for this {@link Entry}. Statistics should
+         *                represent the contents of IP packets, including IP headers.
+         * @param rxPackets Number of packets received for this {@link Entry}. Statistics should
+         *                  represent the contents of IP packets, including IP headers.
+         * @param txBytes Number of bytes transmitted for this {@link Entry}. Statistics should
+         *                represent the contents of IP packets, including IP headers.
+         * @param txPackets Number of bytes transmitted for this {@link Entry}. Statistics should
+         *                  represent the contents of IP packets, including IP headers.
+         * @param operations count of network operations performed for this {@link Entry}. This can
+         *                   be used to derive bytes-per-operation.
+         */
+        public Entry(@Nullable String iface, int uid, @State int set, int tag,
+                @Meteredness int metered, @Roaming int roaming, @DefaultNetwork int defaultNetwork,
+                long rxBytes, long rxPackets, long txBytes, long txPackets, long operations) {
+            this.iface = iface;
+            this.uid = uid;
+            this.set = set;
+            this.tag = tag;
+            this.metered = metered;
+            this.roaming = roaming;
+            this.defaultNetwork = defaultNetwork;
+            this.rxBytes = rxBytes;
+            this.rxPackets = rxPackets;
+            this.txBytes = txBytes;
+            this.txPackets = txPackets;
+            this.operations = operations;
+        }
+
+        /** @hide */
+        public boolean isNegative() {
+            return rxBytes < 0 || rxPackets < 0 || txBytes < 0 || txPackets < 0 || operations < 0;
+        }
+
+        /** @hide */
+        public boolean isEmpty() {
+            return rxBytes == 0 && rxPackets == 0 && txBytes == 0 && txPackets == 0
+                    && operations == 0;
+        }
+
+        /** @hide */
+        public void add(Entry another) {
+            this.rxBytes += another.rxBytes;
+            this.rxPackets += another.rxPackets;
+            this.txBytes += another.txBytes;
+            this.txPackets += another.txPackets;
+            this.operations += another.operations;
+        }
+
+        @Override
+        public String toString() {
+            final StringBuilder builder = new StringBuilder();
+            builder.append("iface=").append(iface);
+            builder.append(" uid=").append(uid);
+            builder.append(" set=").append(setToString(set));
+            builder.append(" tag=").append(tagToString(tag));
+            builder.append(" metered=").append(meteredToString(metered));
+            builder.append(" roaming=").append(roamingToString(roaming));
+            builder.append(" defaultNetwork=").append(defaultNetworkToString(defaultNetwork));
+            builder.append(" rxBytes=").append(rxBytes);
+            builder.append(" rxPackets=").append(rxPackets);
+            builder.append(" txBytes=").append(txBytes);
+            builder.append(" txPackets=").append(txPackets);
+            builder.append(" operations=").append(operations);
+            return builder.toString();
+        }
+
+        /** @hide */
+        @Override
+        public boolean equals(@Nullable Object o) {
+            if (o instanceof Entry) {
+                final Entry e = (Entry) o;
+                return uid == e.uid && set == e.set && tag == e.tag && metered == e.metered
+                        && roaming == e.roaming && defaultNetwork == e.defaultNetwork
+                        && rxBytes == e.rxBytes && rxPackets == e.rxPackets
+                        && txBytes == e.txBytes && txPackets == e.txPackets
+                        && operations == e.operations && iface.equals(e.iface);
+            }
+            return false;
+        }
+
+        /** @hide */
+        @Override
+        public int hashCode() {
+            return Objects.hash(uid, set, tag, metered, roaming, defaultNetwork, iface);
+        }
+    }
+
+    public NetworkStats(long elapsedRealtime, int initialSize) {
+        this.elapsedRealtime = elapsedRealtime;
+        this.size = 0;
+        if (initialSize > 0) {
+            this.capacity = initialSize;
+            this.iface = new String[initialSize];
+            this.uid = new int[initialSize];
+            this.set = new int[initialSize];
+            this.tag = new int[initialSize];
+            this.metered = new int[initialSize];
+            this.roaming = new int[initialSize];
+            this.defaultNetwork = new int[initialSize];
+            this.rxBytes = new long[initialSize];
+            this.rxPackets = new long[initialSize];
+            this.txBytes = new long[initialSize];
+            this.txPackets = new long[initialSize];
+            this.operations = new long[initialSize];
+        } else {
+            // Special case for use by NetworkStatsFactory to start out *really* empty.
+            clear();
+        }
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public NetworkStats(Parcel parcel) {
+        elapsedRealtime = parcel.readLong();
+        size = parcel.readInt();
+        capacity = parcel.readInt();
+        iface = parcel.createStringArray();
+        uid = parcel.createIntArray();
+        set = parcel.createIntArray();
+        tag = parcel.createIntArray();
+        metered = parcel.createIntArray();
+        roaming = parcel.createIntArray();
+        defaultNetwork = parcel.createIntArray();
+        rxBytes = parcel.createLongArray();
+        rxPackets = parcel.createLongArray();
+        txBytes = parcel.createLongArray();
+        txPackets = parcel.createLongArray();
+        operations = parcel.createLongArray();
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        dest.writeLong(elapsedRealtime);
+        dest.writeInt(size);
+        dest.writeInt(capacity);
+        dest.writeStringArray(iface);
+        dest.writeIntArray(uid);
+        dest.writeIntArray(set);
+        dest.writeIntArray(tag);
+        dest.writeIntArray(metered);
+        dest.writeIntArray(roaming);
+        dest.writeIntArray(defaultNetwork);
+        dest.writeLongArray(rxBytes);
+        dest.writeLongArray(rxPackets);
+        dest.writeLongArray(txBytes);
+        dest.writeLongArray(txPackets);
+        dest.writeLongArray(operations);
+    }
+
+    /**
+     * @hide
+     */
+    @Override
+    public NetworkStats clone() {
+        final NetworkStats clone = new NetworkStats(elapsedRealtime, size);
+        NetworkStats.Entry entry = null;
+        for (int i = 0; i < size; i++) {
+            entry = getValues(i, entry);
+            clone.insertEntry(entry);
+        }
+        return clone;
+    }
+
+    /**
+     * Clear all data stored in this object.
+     * @hide
+     */
+    public void clear() {
+        this.capacity = 0;
+        this.iface = EmptyArray.STRING;
+        this.uid = EmptyArray.INT;
+        this.set = EmptyArray.INT;
+        this.tag = EmptyArray.INT;
+        this.metered = EmptyArray.INT;
+        this.roaming = EmptyArray.INT;
+        this.defaultNetwork = EmptyArray.INT;
+        this.rxBytes = EmptyArray.LONG;
+        this.rxPackets = EmptyArray.LONG;
+        this.txBytes = EmptyArray.LONG;
+        this.txPackets = EmptyArray.LONG;
+        this.operations = EmptyArray.LONG;
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public NetworkStats insertEntry(
+            String iface, long rxBytes, long rxPackets, long txBytes, long txPackets) {
+        return insertEntry(
+                iface, UID_ALL, SET_DEFAULT, TAG_NONE, rxBytes, rxPackets, txBytes, txPackets, 0L);
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public NetworkStats insertEntry(String iface, int uid, int set, int tag, long rxBytes,
+            long rxPackets, long txBytes, long txPackets, long operations) {
+        return insertEntry(new Entry(
+                iface, uid, set, tag, rxBytes, rxPackets, txBytes, txPackets, operations));
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public NetworkStats insertEntry(String iface, int uid, int set, int tag, int metered,
+            int roaming, int defaultNetwork, long rxBytes, long rxPackets, long txBytes,
+            long txPackets, long operations) {
+        return insertEntry(new Entry(
+                iface, uid, set, tag, metered, roaming, defaultNetwork, rxBytes, rxPackets,
+                txBytes, txPackets, operations));
+    }
+
+    /**
+     * Add new stats entry, copying from given {@link Entry}. The {@link Entry}
+     * object can be recycled across multiple calls.
+     * @hide
+     */
+    public NetworkStats insertEntry(Entry entry) {
+        if (size >= capacity) {
+            final int newLength = Math.max(size, 10) * 3 / 2;
+            iface = Arrays.copyOf(iface, newLength);
+            uid = Arrays.copyOf(uid, newLength);
+            set = Arrays.copyOf(set, newLength);
+            tag = Arrays.copyOf(tag, newLength);
+            metered = Arrays.copyOf(metered, newLength);
+            roaming = Arrays.copyOf(roaming, newLength);
+            defaultNetwork = Arrays.copyOf(defaultNetwork, newLength);
+            rxBytes = Arrays.copyOf(rxBytes, newLength);
+            rxPackets = Arrays.copyOf(rxPackets, newLength);
+            txBytes = Arrays.copyOf(txBytes, newLength);
+            txPackets = Arrays.copyOf(txPackets, newLength);
+            operations = Arrays.copyOf(operations, newLength);
+            capacity = newLength;
+        }
+
+        setValues(size, entry);
+        size++;
+
+        return this;
+    }
+
+    private void setValues(int i, Entry entry) {
+        iface[i] = entry.iface;
+        uid[i] = entry.uid;
+        set[i] = entry.set;
+        tag[i] = entry.tag;
+        metered[i] = entry.metered;
+        roaming[i] = entry.roaming;
+        defaultNetwork[i] = entry.defaultNetwork;
+        rxBytes[i] = entry.rxBytes;
+        rxPackets[i] = entry.rxPackets;
+        txBytes[i] = entry.txBytes;
+        txPackets[i] = entry.txPackets;
+        operations[i] = entry.operations;
+    }
+
+    /**
+     * Return specific stats entry.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public Entry getValues(int i, Entry recycle) {
+        final Entry entry = recycle != null ? recycle : new Entry();
+        entry.iface = iface[i];
+        entry.uid = uid[i];
+        entry.set = set[i];
+        entry.tag = tag[i];
+        entry.metered = metered[i];
+        entry.roaming = roaming[i];
+        entry.defaultNetwork = defaultNetwork[i];
+        entry.rxBytes = rxBytes[i];
+        entry.rxPackets = rxPackets[i];
+        entry.txBytes = txBytes[i];
+        entry.txPackets = txPackets[i];
+        entry.operations = operations[i];
+        return entry;
+    }
+
+    /**
+     * If @{code dest} is not equal to @{code src}, copy entry from index @{code src} to index
+     * @{code dest}.
+     */
+    private void maybeCopyEntry(int dest, int src) {
+        if (dest == src) return;
+        iface[dest] = iface[src];
+        uid[dest] = uid[src];
+        set[dest] = set[src];
+        tag[dest] = tag[src];
+        metered[dest] = metered[src];
+        roaming[dest] = roaming[src];
+        defaultNetwork[dest] = defaultNetwork[src];
+        rxBytes[dest] = rxBytes[src];
+        rxPackets[dest] = rxPackets[src];
+        txBytes[dest] = txBytes[src];
+        txPackets[dest] = txPackets[src];
+        operations[dest] = operations[src];
+    }
+
+    /** @hide */
+    public long getElapsedRealtime() {
+        return elapsedRealtime;
+    }
+
+    /** @hide */
+    public void setElapsedRealtime(long time) {
+        elapsedRealtime = time;
+    }
+
+    /**
+     * Return age of this {@link NetworkStats} object with respect to
+     * {@link SystemClock#elapsedRealtime()}.
+     * @hide
+     */
+    public long getElapsedRealtimeAge() {
+        return SystemClock.elapsedRealtime() - elapsedRealtime;
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage
+    public int size() {
+        return size;
+    }
+
+    /** @hide */
+    @VisibleForTesting
+    public int internalSize() {
+        return capacity;
+    }
+
+    /** @hide */
+    @Deprecated
+    public NetworkStats combineValues(String iface, int uid, int tag, long rxBytes, long rxPackets,
+            long txBytes, long txPackets, long operations) {
+        return combineValues(
+                iface, uid, SET_DEFAULT, tag, rxBytes, rxPackets, txBytes,
+                txPackets, operations);
+    }
+
+    /** @hide */
+    public NetworkStats combineValues(String iface, int uid, int set, int tag,
+            long rxBytes, long rxPackets, long txBytes, long txPackets, long operations) {
+        return combineValues(new Entry(
+                iface, uid, set, tag, rxBytes, rxPackets, txBytes, txPackets, operations));
+    }
+
+    /**
+     * Combine given values with an existing row, or create a new row if
+     * {@link #findIndex(String, int, int, int, int, int, int)} is unable to find match. Can
+     * also be used to subtract values from existing rows. This method mutates the referencing
+     * {@link NetworkStats} object.
+     *
+     * @param entry the {@link Entry} to combine.
+     * @return a reference to this mutated {@link NetworkStats} object.
+     * @hide
+     */
+    public @NonNull NetworkStats combineValues(@NonNull Entry entry) {
+        final int i = findIndex(entry.iface, entry.uid, entry.set, entry.tag, entry.metered,
+                entry.roaming, entry.defaultNetwork);
+        if (i == -1) {
+            // only create new entry when positive contribution
+            insertEntry(entry);
+        } else {
+            rxBytes[i] += entry.rxBytes;
+            rxPackets[i] += entry.rxPackets;
+            txBytes[i] += entry.txBytes;
+            txPackets[i] += entry.txPackets;
+            operations[i] += entry.operations;
+        }
+        return this;
+    }
+
+    /**
+     * Add given values with an existing row, or create a new row if
+     * {@link #findIndex(String, int, int, int, int, int, int)} is unable to find match. Can
+     * also be used to subtract values from existing rows.
+     *
+     * @param entry the {@link Entry} to add.
+     * @return a new constructed {@link NetworkStats} object that contains the result.
+     */
+    public @NonNull NetworkStats addEntry(@NonNull Entry entry) {
+        return this.clone().combineValues(entry);
+    }
+
+    /**
+     * Add the given {@link NetworkStats} objects.
+     *
+     * @return the sum of two objects.
+     */
+    public @NonNull NetworkStats add(@NonNull NetworkStats another) {
+        final NetworkStats ret = this.clone();
+        ret.combineAllValues(another);
+        return ret;
+    }
+
+    /**
+     * Combine all values from another {@link NetworkStats} into this object.
+     * @hide
+     */
+    public void combineAllValues(@NonNull NetworkStats another) {
+        NetworkStats.Entry entry = null;
+        for (int i = 0; i < another.size; i++) {
+            entry = another.getValues(i, entry);
+            combineValues(entry);
+        }
+    }
+
+    /**
+     * Find first stats index that matches the requested parameters.
+     * @hide
+     */
+    public int findIndex(String iface, int uid, int set, int tag, int metered, int roaming,
+            int defaultNetwork) {
+        for (int i = 0; i < size; i++) {
+            if (uid == this.uid[i] && set == this.set[i] && tag == this.tag[i]
+                    && metered == this.metered[i] && roaming == this.roaming[i]
+                    && defaultNetwork == this.defaultNetwork[i]
+                    && Objects.equals(iface, this.iface[i])) {
+                return i;
+            }
+        }
+        return -1;
+    }
+
+    /**
+     * Find first stats index that matches the requested parameters, starting
+     * search around the hinted index as an optimization.
+     * @hide
+     */
+    @VisibleForTesting
+    public int findIndexHinted(String iface, int uid, int set, int tag, int metered, int roaming,
+            int defaultNetwork, int hintIndex) {
+        for (int offset = 0; offset < size; offset++) {
+            final int halfOffset = offset / 2;
+
+            // search outwards from hint index, alternating forward and backward
+            final int i;
+            if (offset % 2 == 0) {
+                i = (hintIndex + halfOffset) % size;
+            } else {
+                i = (size + hintIndex - halfOffset - 1) % size;
+            }
+
+            if (uid == this.uid[i] && set == this.set[i] && tag == this.tag[i]
+                    && metered == this.metered[i] && roaming == this.roaming[i]
+                    && defaultNetwork == this.defaultNetwork[i]
+                    && Objects.equals(iface, this.iface[i])) {
+                return i;
+            }
+        }
+        return -1;
+    }
+
+    /**
+     * Splice in {@link #operations} from the given {@link NetworkStats} based
+     * on matching {@link #uid} and {@link #tag} rows. Ignores {@link #iface},
+     * since operation counts are at data layer.
+     * @hide
+     */
+    public void spliceOperationsFrom(NetworkStats stats) {
+        for (int i = 0; i < size; i++) {
+            final int j = stats.findIndex(iface[i], uid[i], set[i], tag[i], metered[i], roaming[i],
+                    defaultNetwork[i]);
+            if (j == -1) {
+                operations[i] = 0;
+            } else {
+                operations[i] = stats.operations[j];
+            }
+        }
+    }
+
+    /**
+     * Return list of unique interfaces known by this data structure.
+     * @hide
+     */
+    public String[] getUniqueIfaces() {
+        final HashSet<String> ifaces = new HashSet<String>();
+        for (String iface : this.iface) {
+            if (iface != IFACE_ALL) {
+                ifaces.add(iface);
+            }
+        }
+        return ifaces.toArray(new String[ifaces.size()]);
+    }
+
+    /**
+     * Return list of unique UIDs known by this data structure.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public int[] getUniqueUids() {
+        final SparseBooleanArray uids = new SparseBooleanArray();
+        for (int uid : this.uid) {
+            uids.put(uid, true);
+        }
+
+        final int size = uids.size();
+        final int[] result = new int[size];
+        for (int i = 0; i < size; i++) {
+            result[i] = uids.keyAt(i);
+        }
+        return result;
+    }
+
+    /**
+     * Return total bytes represented by this snapshot object, usually used when
+     * checking if a {@link #subtract(NetworkStats)} delta passes a threshold.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public long getTotalBytes() {
+        final Entry entry = getTotal(null);
+        return entry.rxBytes + entry.txBytes;
+    }
+
+    /**
+     * Return total of all fields represented by this snapshot object.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public Entry getTotal(Entry recycle) {
+        return getTotal(recycle, null, UID_ALL, false);
+    }
+
+    /**
+     * Return total of all fields represented by this snapshot object matching
+     * the requested {@link #uid}.
+     * @hide
+     */
+    @UnsupportedAppUsage
+    public Entry getTotal(Entry recycle, int limitUid) {
+        return getTotal(recycle, null, limitUid, false);
+    }
+
+    /**
+     * Return total of all fields represented by this snapshot object matching
+     * the requested {@link #iface}.
+     * @hide
+     */
+    public Entry getTotal(Entry recycle, HashSet<String> limitIface) {
+        return getTotal(recycle, limitIface, UID_ALL, false);
+    }
+
+    /** @hide */
+    @UnsupportedAppUsage
+    public Entry getTotalIncludingTags(Entry recycle) {
+        return getTotal(recycle, null, UID_ALL, true);
+    }
+
+    /**
+     * Return total of all fields represented by this snapshot object matching
+     * the requested {@link #iface} and {@link #uid}.
+     *
+     * @param limitIface Set of {@link #iface} to include in total; or {@code
+     *            null} to include all ifaces.
+     */
+    private Entry getTotal(
+            Entry recycle, HashSet<String> limitIface, int limitUid, boolean includeTags) {
+        final Entry entry = recycle != null ? recycle : new Entry();
+
+        entry.iface = IFACE_ALL;
+        entry.uid = limitUid;
+        entry.set = SET_ALL;
+        entry.tag = TAG_NONE;
+        entry.metered = METERED_ALL;
+        entry.roaming = ROAMING_ALL;
+        entry.defaultNetwork = DEFAULT_NETWORK_ALL;
+        entry.rxBytes = 0;
+        entry.rxPackets = 0;
+        entry.txBytes = 0;
+        entry.txPackets = 0;
+        entry.operations = 0;
+
+        for (int i = 0; i < size; i++) {
+            final boolean matchesUid = (limitUid == UID_ALL) || (limitUid == uid[i]);
+            final boolean matchesIface = (limitIface == null) || (limitIface.contains(iface[i]));
+
+            if (matchesUid && matchesIface) {
+                // skip specific tags, since already counted in TAG_NONE
+                if (tag[i] != TAG_NONE && !includeTags) continue;
+
+                entry.rxBytes += rxBytes[i];
+                entry.rxPackets += rxPackets[i];
+                entry.txBytes += txBytes[i];
+                entry.txPackets += txPackets[i];
+                entry.operations += operations[i];
+            }
+        }
+        return entry;
+    }
+
+    /**
+     * Fast path for battery stats.
+     * @hide
+     */
+    public long getTotalPackets() {
+        long total = 0;
+        for (int i = size-1; i >= 0; i--) {
+            total += rxPackets[i] + txPackets[i];
+        }
+        return total;
+    }
+
+    /**
+     * Subtract the given {@link NetworkStats}, effectively leaving the delta
+     * between two snapshots in time. Assumes that statistics rows collect over
+     * time, and that none of them have disappeared. This method does not mutate
+     * the referencing object.
+     *
+     * @return the delta between two objects.
+     */
+    public @NonNull NetworkStats subtract(@NonNull NetworkStats right) {
+        return subtract(this, right, null, null);
+    }
+
+    /**
+     * Subtract the two given {@link NetworkStats} objects, returning the delta
+     * between two snapshots in time. Assumes that statistics rows collect over
+     * time, and that none of them have disappeared.
+     * <p>
+     * If counters have rolled backwards, they are clamped to {@code 0} and
+     * reported to the given {@link NonMonotonicObserver}.
+     * @hide
+     */
+    public static <C> NetworkStats subtract(NetworkStats left, NetworkStats right,
+            NonMonotonicObserver<C> observer, C cookie) {
+        return subtract(left, right, observer, cookie, null);
+    }
+
+    /**
+     * Subtract the two given {@link NetworkStats} objects, returning the delta
+     * between two snapshots in time. Assumes that statistics rows collect over
+     * time, and that none of them have disappeared.
+     * <p>
+     * If counters have rolled backwards, they are clamped to {@code 0} and
+     * reported to the given {@link NonMonotonicObserver}.
+     * <p>
+     * If <var>recycle</var> is supplied, this NetworkStats object will be
+     * reused (and returned) as the result if it is large enough to contain
+     * the data.
+     * @hide
+     */
+    public static <C> NetworkStats subtract(NetworkStats left, NetworkStats right,
+            NonMonotonicObserver<C> observer, C cookie, NetworkStats recycle) {
+        long deltaRealtime = left.elapsedRealtime - right.elapsedRealtime;
+        if (deltaRealtime < 0) {
+            if (observer != null) {
+                observer.foundNonMonotonic(left, -1, right, -1, cookie);
+            }
+            deltaRealtime = 0;
+        }
+
+        // result will have our rows, and elapsed time between snapshots
+        final Entry entry = new Entry();
+        final NetworkStats result;
+        if (recycle != null && recycle.capacity >= left.size) {
+            result = recycle;
+            result.size = 0;
+            result.elapsedRealtime = deltaRealtime;
+        } else {
+            result = new NetworkStats(deltaRealtime, left.size);
+        }
+        for (int i = 0; i < left.size; i++) {
+            entry.iface = left.iface[i];
+            entry.uid = left.uid[i];
+            entry.set = left.set[i];
+            entry.tag = left.tag[i];
+            entry.metered = left.metered[i];
+            entry.roaming = left.roaming[i];
+            entry.defaultNetwork = left.defaultNetwork[i];
+            entry.rxBytes = left.rxBytes[i];
+            entry.rxPackets = left.rxPackets[i];
+            entry.txBytes = left.txBytes[i];
+            entry.txPackets = left.txPackets[i];
+            entry.operations = left.operations[i];
+
+            // find remote row that matches, and subtract
+            final int j = right.findIndexHinted(entry.iface, entry.uid, entry.set, entry.tag,
+                    entry.metered, entry.roaming, entry.defaultNetwork, i);
+            if (j != -1) {
+                // Found matching row, subtract remote value.
+                entry.rxBytes -= right.rxBytes[j];
+                entry.rxPackets -= right.rxPackets[j];
+                entry.txBytes -= right.txBytes[j];
+                entry.txPackets -= right.txPackets[j];
+                entry.operations -= right.operations[j];
+            }
+
+            if (entry.isNegative()) {
+                if (observer != null) {
+                    observer.foundNonMonotonic(left, i, right, j, cookie);
+                }
+                entry.rxBytes = Math.max(entry.rxBytes, 0);
+                entry.rxPackets = Math.max(entry.rxPackets, 0);
+                entry.txBytes = Math.max(entry.txBytes, 0);
+                entry.txPackets = Math.max(entry.txPackets, 0);
+                entry.operations = Math.max(entry.operations, 0);
+            }
+
+            result.insertEntry(entry);
+        }
+
+        return result;
+    }
+
+    /**
+     * Calculate and apply adjustments to captured statistics for 464xlat traffic.
+     *
+     * <p>This mutates stacked traffic stats, to account for IPv4/IPv6 header size difference.
+     *
+     * <p>UID stats, which are only accounted on the stacked interface, need to be increased
+     * by 20 bytes/packet to account for translation overhead.
+     *
+     * <p>The potential additional overhead of 8 bytes/packet for ip fragments is ignored.
+     *
+     * <p>Interface stats need to sum traffic on both stacked and base interface because:
+     *   - eBPF offloaded packets appear only on the stacked interface
+     *   - Non-offloaded ingress packets appear only on the stacked interface
+     *     (due to iptables raw PREROUTING drop rules)
+     *   - Non-offloaded egress packets appear only on the stacked interface
+     *     (due to ignoring traffic from clat daemon by uid match)
+     * (and of course the 20 bytes/packet overhead needs to be applied to stacked interface stats)
+     *
+     * <p>This method will behave fine if {@code stackedIfaces} is an non-synchronized but add-only
+     * {@code ConcurrentHashMap}
+     * @param baseTraffic Traffic on the base interfaces. Will be mutated.
+     * @param stackedTraffic Stats with traffic stacked on top of our ifaces. Will also be mutated.
+     * @param stackedIfaces Mapping ipv6if -> ipv4if interface where traffic is counted on both.
+     * @hide
+     */
+    public static void apply464xlatAdjustments(NetworkStats baseTraffic,
+            NetworkStats stackedTraffic, Map<String, String> stackedIfaces) {
+        // For recycling
+        Entry entry = null;
+        for (int i = 0; i < stackedTraffic.size; i++) {
+            entry = stackedTraffic.getValues(i, entry);
+            if (entry == null) continue;
+            if (entry.iface == null) continue;
+            if (!entry.iface.startsWith(CLATD_INTERFACE_PREFIX)) continue;
+
+            // For 464xlat traffic, per uid stats only counts the bytes of the native IPv4 packet
+            // sent on the stacked interface with prefix "v4-" and drops the IPv6 header size after
+            // unwrapping. To account correctly for on-the-wire traffic, add the 20 additional bytes
+            // difference for all packets (http://b/12249687, http:/b/33681750).
+            //
+            // Note: this doesn't account for LRO/GRO/GSO/TSO (ie. >mtu) traffic correctly, nor
+            // does it correctly account for the 8 extra bytes in the IPv6 fragmentation header.
+            //
+            // While the ebpf code path does try to simulate proper post segmentation packet
+            // counts, we have nothing of the sort of xt_qtaguid stats.
+            entry.rxBytes += entry.rxPackets * IPV4V6_HEADER_DELTA;
+            entry.txBytes += entry.txPackets * IPV4V6_HEADER_DELTA;
+            stackedTraffic.setValues(i, entry);
+        }
+    }
+
+    /**
+     * Calculate and apply adjustments to captured statistics for 464xlat traffic counted twice.
+     *
+     * <p>This mutates the object this method is called on. Equivalent to calling
+     * {@link #apply464xlatAdjustments(NetworkStats, NetworkStats, Map)} with {@code this} as
+     * base and stacked traffic.
+     * @param stackedIfaces Mapping ipv6if -> ipv4if interface where traffic is counted on both.
+     * @hide
+     */
+    public void apply464xlatAdjustments(Map<String, String> stackedIfaces) {
+        apply464xlatAdjustments(this, this, stackedIfaces);
+    }
+
+    /**
+     * Return total statistics grouped by {@link #iface}; doesn't mutate the
+     * original structure.
+     * @hide
+     */
+    public NetworkStats groupedByIface() {
+        final NetworkStats stats = new NetworkStats(elapsedRealtime, 10);
+
+        final Entry entry = new Entry();
+        entry.uid = UID_ALL;
+        entry.set = SET_ALL;
+        entry.tag = TAG_NONE;
+        entry.metered = METERED_ALL;
+        entry.roaming = ROAMING_ALL;
+        entry.defaultNetwork = DEFAULT_NETWORK_ALL;
+        entry.operations = 0L;
+
+        for (int i = 0; i < size; i++) {
+            // skip specific tags, since already counted in TAG_NONE
+            if (tag[i] != TAG_NONE) continue;
+
+            entry.iface = iface[i];
+            entry.rxBytes = rxBytes[i];
+            entry.rxPackets = rxPackets[i];
+            entry.txBytes = txBytes[i];
+            entry.txPackets = txPackets[i];
+            stats.combineValues(entry);
+        }
+
+        return stats;
+    }
+
+    /**
+     * Return total statistics grouped by {@link #uid}; doesn't mutate the
+     * original structure.
+     * @hide
+     */
+    public NetworkStats groupedByUid() {
+        final NetworkStats stats = new NetworkStats(elapsedRealtime, 10);
+
+        final Entry entry = new Entry();
+        entry.iface = IFACE_ALL;
+        entry.set = SET_ALL;
+        entry.tag = TAG_NONE;
+        entry.metered = METERED_ALL;
+        entry.roaming = ROAMING_ALL;
+        entry.defaultNetwork = DEFAULT_NETWORK_ALL;
+
+        for (int i = 0; i < size; i++) {
+            // skip specific tags, since already counted in TAG_NONE
+            if (tag[i] != TAG_NONE) continue;
+
+            entry.uid = uid[i];
+            entry.rxBytes = rxBytes[i];
+            entry.rxPackets = rxPackets[i];
+            entry.txBytes = txBytes[i];
+            entry.txPackets = txPackets[i];
+            entry.operations = operations[i];
+            stats.combineValues(entry);
+        }
+
+        return stats;
+    }
+
+    /**
+     * Remove all rows that match one of specified UIDs.
+     * This mutates the original structure in place.
+     * @hide
+     */
+    public void removeUids(int[] uids) {
+        filter(e -> !ArrayUtils.contains(uids, e.uid));
+    }
+
+    /**
+     * Remove all rows that match one of specified UIDs.
+     * @return the result object.
+     * @hide
+     */
+    @NonNull
+    public NetworkStats removeEmptyEntries() {
+        final NetworkStats ret = this.clone();
+        ret.filter(e -> e.rxBytes != 0 || e.rxPackets != 0 || e.txBytes != 0 || e.txPackets != 0
+                || e.operations != 0);
+        return ret;
+    }
+
+    /**
+     * Only keep entries that match all specified filters.
+     *
+     * <p>This mutates the original structure in place. After this method is called,
+     * size is the number of matching entries, and capacity is the previous capacity.
+     * @param limitUid UID to filter for, or {@link #UID_ALL}.
+     * @param limitIfaces Interfaces to filter for, or {@link #INTERFACES_ALL}.
+     * @param limitTag Tag to filter for, or {@link #TAG_ALL}.
+     * @hide
+     */
+    public void filter(int limitUid, String[] limitIfaces, int limitTag) {
+        if (limitUid == UID_ALL && limitTag == TAG_ALL && limitIfaces == INTERFACES_ALL) {
+            return;
+        }
+        filter(e -> (limitUid == UID_ALL || limitUid == e.uid)
+                && (limitTag == TAG_ALL || limitTag == e.tag)
+                && (limitIfaces == INTERFACES_ALL
+                    || ArrayUtils.contains(limitIfaces, e.iface)));
+    }
+
+    /**
+     * Only keep entries with {@link #set} value less than {@link #SET_DEBUG_START}.
+     *
+     * <p>This mutates the original structure in place.
+     * @hide
+     */
+    public void filterDebugEntries() {
+        filter(e -> e.set < SET_DEBUG_START);
+    }
+
+    private void filter(Predicate<Entry> predicate) {
+        Entry entry = new Entry();
+        int nextOutputEntry = 0;
+        for (int i = 0; i < size; i++) {
+            entry = getValues(i, entry);
+            if (predicate.test(entry)) {
+                if (nextOutputEntry != i) {
+                    setValues(nextOutputEntry, entry);
+                }
+                nextOutputEntry++;
+            }
+        }
+        size = nextOutputEntry;
+    }
+
+    /** @hide */
+    public void dump(String prefix, PrintWriter pw) {
+        pw.print(prefix);
+        pw.print("NetworkStats: elapsedRealtime="); pw.println(elapsedRealtime);
+        for (int i = 0; i < size; i++) {
+            pw.print(prefix);
+            pw.print("  ["); pw.print(i); pw.print("]");
+            pw.print(" iface="); pw.print(iface[i]);
+            pw.print(" uid="); pw.print(uid[i]);
+            pw.print(" set="); pw.print(setToString(set[i]));
+            pw.print(" tag="); pw.print(tagToString(tag[i]));
+            pw.print(" metered="); pw.print(meteredToString(metered[i]));
+            pw.print(" roaming="); pw.print(roamingToString(roaming[i]));
+            pw.print(" defaultNetwork="); pw.print(defaultNetworkToString(defaultNetwork[i]));
+            pw.print(" rxBytes="); pw.print(rxBytes[i]);
+            pw.print(" rxPackets="); pw.print(rxPackets[i]);
+            pw.print(" txBytes="); pw.print(txBytes[i]);
+            pw.print(" txPackets="); pw.print(txPackets[i]);
+            pw.print(" operations="); pw.println(operations[i]);
+        }
+    }
+
+    /**
+     * Return text description of {@link #set} value.
+     * @hide
+     */
+    public static String setToString(int set) {
+        switch (set) {
+            case SET_ALL:
+                return "ALL";
+            case SET_DEFAULT:
+                return "DEFAULT";
+            case SET_FOREGROUND:
+                return "FOREGROUND";
+            case SET_DBG_VPN_IN:
+                return "DBG_VPN_IN";
+            case SET_DBG_VPN_OUT:
+                return "DBG_VPN_OUT";
+            default:
+                return "UNKNOWN";
+        }
+    }
+
+    /**
+     * Return text description of {@link #set} value.
+     * @hide
+     */
+    public static String setToCheckinString(int set) {
+        switch (set) {
+            case SET_ALL:
+                return "all";
+            case SET_DEFAULT:
+                return "def";
+            case SET_FOREGROUND:
+                return "fg";
+            case SET_DBG_VPN_IN:
+                return "vpnin";
+            case SET_DBG_VPN_OUT:
+                return "vpnout";
+            default:
+                return "unk";
+        }
+    }
+
+    /**
+     * @return true if the querySet matches the dataSet.
+     * @hide
+     */
+    public static boolean setMatches(int querySet, int dataSet) {
+        if (querySet == dataSet) {
+            return true;
+        }
+        // SET_ALL matches all non-debugging sets.
+        return querySet == SET_ALL && dataSet < SET_DEBUG_START;
+    }
+
+    /**
+     * Return text description of {@link #tag} value.
+     * @hide
+     */
+    public static String tagToString(int tag) {
+        return "0x" + Integer.toHexString(tag);
+    }
+
+    /**
+     * Return text description of {@link #metered} value.
+     * @hide
+     */
+    public static String meteredToString(int metered) {
+        switch (metered) {
+            case METERED_ALL:
+                return "ALL";
+            case METERED_NO:
+                return "NO";
+            case METERED_YES:
+                return "YES";
+            default:
+                return "UNKNOWN";
+        }
+    }
+
+    /**
+     * Return text description of {@link #roaming} value.
+     * @hide
+     */
+    public static String roamingToString(int roaming) {
+        switch (roaming) {
+            case ROAMING_ALL:
+                return "ALL";
+            case ROAMING_NO:
+                return "NO";
+            case ROAMING_YES:
+                return "YES";
+            default:
+                return "UNKNOWN";
+        }
+    }
+
+    /**
+     * Return text description of {@link #defaultNetwork} value.
+     * @hide
+     */
+    public static String defaultNetworkToString(int defaultNetwork) {
+        switch (defaultNetwork) {
+            case DEFAULT_NETWORK_ALL:
+                return "ALL";
+            case DEFAULT_NETWORK_NO:
+                return "NO";
+            case DEFAULT_NETWORK_YES:
+                return "YES";
+            default:
+                return "UNKNOWN";
+        }
+    }
+
+    /** @hide */
+    @Override
+    public String toString() {
+        final CharArrayWriter writer = new CharArrayWriter();
+        dump("", new PrintWriter(writer));
+        return writer.toString();
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    public static final @NonNull Creator<NetworkStats> CREATOR = new Creator<NetworkStats>() {
+        @Override
+        public NetworkStats createFromParcel(Parcel in) {
+            return new NetworkStats(in);
+        }
+
+        @Override
+        public NetworkStats[] newArray(int size) {
+            return new NetworkStats[size];
+        }
+    };
+
+    /** @hide */
+    public interface NonMonotonicObserver<C> {
+        public void foundNonMonotonic(
+                NetworkStats left, int leftIndex, NetworkStats right, int rightIndex, C cookie);
+        public void foundNonMonotonic(
+                NetworkStats stats, int statsIndex, C cookie);
+    }
+
+    /**
+     * VPN accounting. Move some VPN's underlying traffic to other UIDs that use tun0 iface.
+     *
+     * <p>This method should only be called on delta NetworkStats. Do not call this method on a
+     * snapshot {@link NetworkStats} object because the tunUid and/or the underlyingIface may change
+     * over time.
+     *
+     * <p>This method performs adjustments for one active VPN package and one VPN iface at a time.
+     *
+     * @param tunUid uid of the VPN application
+     * @param tunIface iface of the vpn tunnel
+     * @param underlyingIfaces underlying network ifaces used by the VPN application
+     * @hide
+     */
+    public void migrateTun(int tunUid, @NonNull String tunIface,
+            @NonNull List<String> underlyingIfaces) {
+        // Combined usage by all apps using VPN.
+        final Entry tunIfaceTotal = new Entry();
+        // Usage by VPN, grouped by its {@code underlyingIfaces}.
+        final Entry[] perInterfaceTotal = new Entry[underlyingIfaces.size()];
+        // Usage by VPN, summed across all its {@code underlyingIfaces}.
+        final Entry underlyingIfacesTotal = new Entry();
+
+        for (int i = 0; i < perInterfaceTotal.length; i++) {
+            perInterfaceTotal[i] = new Entry();
+        }
+
+        tunAdjustmentInit(tunUid, tunIface, underlyingIfaces, tunIfaceTotal, perInterfaceTotal,
+                underlyingIfacesTotal);
+
+        // If tunIface < underlyingIfacesTotal, it leaves the overhead traffic in the VPN app.
+        // If tunIface > underlyingIfacesTotal, the VPN app doesn't get credit for data compression.
+        // Negative stats should be avoided.
+        final Entry[] moved =
+                addTrafficToApplications(tunUid, tunIface, underlyingIfaces, tunIfaceTotal,
+                        perInterfaceTotal, underlyingIfacesTotal);
+        deductTrafficFromVpnApp(tunUid, underlyingIfaces, moved);
+    }
+
+    /**
+     * Initializes the data used by the migrateTun() method.
+     *
+     * <p>This is the first pass iteration which does the following work:
+     *
+     * <ul>
+     *   <li>Adds up all the traffic through the tunUid's underlyingIfaces (both foreground and
+     *       background).
+     *   <li>Adds up all the traffic through tun0 excluding traffic from the vpn app itself.
+     * </ul>
+     *
+     * @param tunUid uid of the VPN application
+     * @param tunIface iface of the vpn tunnel
+     * @param underlyingIfaces underlying network ifaces used by the VPN application
+     * @param tunIfaceTotal output parameter; combined data usage by all apps using VPN
+     * @param perInterfaceTotal output parameter; data usage by VPN app, grouped by its {@code
+     *     underlyingIfaces}
+     * @param underlyingIfacesTotal output parameter; data usage by VPN, summed across all of its
+     *     {@code underlyingIfaces}
+     */
+    private void tunAdjustmentInit(int tunUid, @NonNull String tunIface,
+            @NonNull List<String> underlyingIfaces, @NonNull Entry tunIfaceTotal,
+            @NonNull Entry[] perInterfaceTotal, @NonNull Entry underlyingIfacesTotal) {
+        final Entry recycle = new Entry();
+        for (int i = 0; i < size; i++) {
+            getValues(i, recycle);
+            if (recycle.uid == UID_ALL) {
+                throw new IllegalStateException(
+                        "Cannot adjust VPN accounting on an iface aggregated NetworkStats.");
+            }
+            if (recycle.set == SET_DBG_VPN_IN || recycle.set == SET_DBG_VPN_OUT) {
+                throw new IllegalStateException(
+                        "Cannot adjust VPN accounting on a NetworkStats containing SET_DBG_VPN_*");
+            }
+            if (recycle.tag != TAG_NONE) {
+                // TODO(b/123666283): Take all tags for tunUid into account.
+                continue;
+            }
+
+            if (tunUid == Process.SYSTEM_UID) {
+                // Kernel-based VPN or VCN, traffic sent by apps on the VPN/VCN network
+                //
+                // Since the data is not UID-accounted on underlying networks, just use VPN/VCN
+                // network usage as ground truth. Encrypted traffic on the underlying networks will
+                // never be processed here because encrypted traffic on the underlying interfaces
+                // is not present in UID stats, and this method is only called on UID stats.
+                if (tunIface.equals(recycle.iface)) {
+                    tunIfaceTotal.add(recycle);
+                    underlyingIfacesTotal.add(recycle);
+
+                    // In steady state, there should always be one network, but edge cases may
+                    // result in the network being null (network lost), and thus no underlying
+                    // ifaces is possible.
+                    if (perInterfaceTotal.length > 0) {
+                        // While platform VPNs and VCNs have exactly one underlying network, that
+                        // network may have multiple interfaces (eg for 464xlat). This layer does
+                        // not have the required information to identify which of the interfaces
+                        // were used. Select "any" of the interfaces. Since overhead is already
+                        // lost, this number is an approximation anyways.
+                        perInterfaceTotal[0].add(recycle);
+                    }
+                }
+            } else if (recycle.uid == tunUid) {
+                // VpnService VPN, traffic sent by the VPN app over underlying networks
+                for (int j = 0; j < underlyingIfaces.size(); j++) {
+                    if (Objects.equals(underlyingIfaces.get(j), recycle.iface)) {
+                        perInterfaceTotal[j].add(recycle);
+                        underlyingIfacesTotal.add(recycle);
+                        break;
+                    }
+                }
+            } else if (tunIface.equals(recycle.iface)) {
+                // VpnService VPN; traffic sent by apps on the VPN network
+                tunIfaceTotal.add(recycle);
+            }
+        }
+    }
+
+    /**
+     * Distributes traffic across apps that are using given {@code tunIface}, and returns the total
+     * traffic that should be moved off of {@code tunUid} grouped by {@code underlyingIfaces}.
+     *
+     * @param tunUid uid of the VPN application
+     * @param tunIface iface of the vpn tunnel
+     * @param underlyingIfaces underlying network ifaces used by the VPN application
+     * @param tunIfaceTotal combined data usage across all apps using {@code tunIface}
+     * @param perInterfaceTotal data usage by VPN app, grouped by its {@code underlyingIfaces}
+     * @param underlyingIfacesTotal data usage by VPN, summed across all of its {@code
+     *     underlyingIfaces}
+     */
+    private Entry[] addTrafficToApplications(int tunUid, @NonNull String tunIface,
+            @NonNull List<String> underlyingIfaces, @NonNull Entry tunIfaceTotal,
+            @NonNull Entry[] perInterfaceTotal, @NonNull Entry underlyingIfacesTotal) {
+        // Traffic that should be moved off of each underlying interface for tunUid (see
+        // deductTrafficFromVpnApp below).
+        final Entry[] moved = new Entry[underlyingIfaces.size()];
+        for (int i = 0; i < underlyingIfaces.size(); i++) {
+            moved[i] = new Entry();
+        }
+
+        final Entry tmpEntry = new Entry();
+        final int origSize = size;
+        for (int i = 0; i < origSize; i++) {
+            if (!Objects.equals(iface[i], tunIface)) {
+                // Consider only entries that go onto the VPN interface.
+                continue;
+            }
+
+            if (uid[i] == tunUid && tunUid != Process.SYSTEM_UID) {
+                // Exclude VPN app from the redistribution, as it can choose to create packet
+                // streams by writing to itself.
+                //
+                // However, for platform VPNs, do not exclude the system's usage of the VPN network,
+                // since it is never local-only, and never double counted
+                continue;
+            }
+            tmpEntry.uid = uid[i];
+            tmpEntry.tag = tag[i];
+            tmpEntry.metered = metered[i];
+            tmpEntry.roaming = roaming[i];
+            tmpEntry.defaultNetwork = defaultNetwork[i];
+
+            // In a first pass, compute this entry's total share of data across all
+            // underlyingIfaces. This is computed on the basis of the share of this entry's usage
+            // over tunIface.
+            // TODO: Consider refactoring first pass into a separate helper method.
+            long totalRxBytes = 0;
+            if (tunIfaceTotal.rxBytes > 0) {
+                // Note - The multiplication below should not overflow since NetworkStatsService
+                // processes this every time device has transmitted/received amount equivalent to
+                // global threshold alert (~ 2MB) across all interfaces.
+                final long rxBytesAcrossUnderlyingIfaces =
+                        multiplySafeByRational(underlyingIfacesTotal.rxBytes,
+                                rxBytes[i], tunIfaceTotal.rxBytes);
+                // app must not be blamed for more than it consumed on tunIface
+                totalRxBytes = Math.min(rxBytes[i], rxBytesAcrossUnderlyingIfaces);
+            }
+            long totalRxPackets = 0;
+            if (tunIfaceTotal.rxPackets > 0) {
+                final long rxPacketsAcrossUnderlyingIfaces =
+                        multiplySafeByRational(underlyingIfacesTotal.rxPackets,
+                                rxPackets[i], tunIfaceTotal.rxPackets);
+                totalRxPackets = Math.min(rxPackets[i], rxPacketsAcrossUnderlyingIfaces);
+            }
+            long totalTxBytes = 0;
+            if (tunIfaceTotal.txBytes > 0) {
+                final long txBytesAcrossUnderlyingIfaces =
+                        multiplySafeByRational(underlyingIfacesTotal.txBytes,
+                                txBytes[i], tunIfaceTotal.txBytes);
+                totalTxBytes = Math.min(txBytes[i], txBytesAcrossUnderlyingIfaces);
+            }
+            long totalTxPackets = 0;
+            if (tunIfaceTotal.txPackets > 0) {
+                final long txPacketsAcrossUnderlyingIfaces =
+                        multiplySafeByRational(underlyingIfacesTotal.txPackets,
+                                txPackets[i], tunIfaceTotal.txPackets);
+                totalTxPackets = Math.min(txPackets[i], txPacketsAcrossUnderlyingIfaces);
+            }
+            long totalOperations = 0;
+            if (tunIfaceTotal.operations > 0) {
+                final long operationsAcrossUnderlyingIfaces =
+                        multiplySafeByRational(underlyingIfacesTotal.operations,
+                                operations[i], tunIfaceTotal.operations);
+                totalOperations = Math.min(operations[i], operationsAcrossUnderlyingIfaces);
+            }
+            // In a second pass, distribute these values across interfaces in the proportion that
+            // each interface represents of the total traffic of the underlying interfaces.
+            for (int j = 0; j < underlyingIfaces.size(); j++) {
+                tmpEntry.iface = underlyingIfaces.get(j);
+                tmpEntry.rxBytes = 0;
+                // Reset 'set' to correct value since it gets updated when adding debug info below.
+                tmpEntry.set = set[i];
+                if (underlyingIfacesTotal.rxBytes > 0) {
+                    tmpEntry.rxBytes =
+                            multiplySafeByRational(totalRxBytes,
+                                    perInterfaceTotal[j].rxBytes,
+                                    underlyingIfacesTotal.rxBytes);
+                }
+                tmpEntry.rxPackets = 0;
+                if (underlyingIfacesTotal.rxPackets > 0) {
+                    tmpEntry.rxPackets =
+                            multiplySafeByRational(totalRxPackets,
+                                    perInterfaceTotal[j].rxPackets,
+                                    underlyingIfacesTotal.rxPackets);
+                }
+                tmpEntry.txBytes = 0;
+                if (underlyingIfacesTotal.txBytes > 0) {
+                    tmpEntry.txBytes =
+                            multiplySafeByRational(totalTxBytes,
+                                    perInterfaceTotal[j].txBytes,
+                                    underlyingIfacesTotal.txBytes);
+                }
+                tmpEntry.txPackets = 0;
+                if (underlyingIfacesTotal.txPackets > 0) {
+                    tmpEntry.txPackets =
+                            multiplySafeByRational(totalTxPackets,
+                                    perInterfaceTotal[j].txPackets,
+                                    underlyingIfacesTotal.txPackets);
+                }
+                tmpEntry.operations = 0;
+                if (underlyingIfacesTotal.operations > 0) {
+                    tmpEntry.operations =
+                            multiplySafeByRational(totalOperations,
+                                    perInterfaceTotal[j].operations,
+                                    underlyingIfacesTotal.operations);
+                }
+                // tmpEntry now contains the migrated data of the i-th entry for the j-th underlying
+                // interface. Add that data usage to this object.
+                combineValues(tmpEntry);
+                if (tag[i] == TAG_NONE) {
+                    // Add the migrated data to moved so it is deducted from the VPN app later.
+                    moved[j].add(tmpEntry);
+                    // Add debug info
+                    tmpEntry.set = SET_DBG_VPN_IN;
+                    combineValues(tmpEntry);
+                }
+            }
+        }
+        return moved;
+    }
+
+    private void deductTrafficFromVpnApp(
+            int tunUid,
+            @NonNull List<String> underlyingIfaces,
+            @NonNull Entry[] moved) {
+        if (tunUid == Process.SYSTEM_UID) {
+            // No traffic recorded on a per-UID basis for in-kernel VPN/VCNs over underlying
+            // networks; thus no traffic to deduct.
+            return;
+        }
+
+        for (int i = 0; i < underlyingIfaces.size(); i++) {
+            moved[i].uid = tunUid;
+            // Add debug info
+            moved[i].set = SET_DBG_VPN_OUT;
+            moved[i].tag = TAG_NONE;
+            moved[i].iface = underlyingIfaces.get(i);
+            moved[i].metered = METERED_ALL;
+            moved[i].roaming = ROAMING_ALL;
+            moved[i].defaultNetwork = DEFAULT_NETWORK_ALL;
+            combineValues(moved[i]);
+
+            // Caveat: if the vpn software uses tag, the total tagged traffic may be greater than
+            // the TAG_NONE traffic.
+            //
+            // Relies on the fact that the underlying traffic only has state ROAMING_NO and
+            // METERED_NO, which should be the case as it comes directly from the /proc file.
+            // We only blend in the roaming data after applying these adjustments, by checking the
+            // NetworkIdentity of the underlying iface.
+            final int idxVpnBackground = findIndex(underlyingIfaces.get(i), tunUid, SET_DEFAULT,
+                            TAG_NONE, METERED_NO, ROAMING_NO, DEFAULT_NETWORK_NO);
+            if (idxVpnBackground != -1) {
+                // Note - tunSubtract also updates moved[i]; whatever traffic that's left is removed
+                // from foreground usage.
+                tunSubtract(idxVpnBackground, this, moved[i]);
+            }
+
+            final int idxVpnForeground = findIndex(underlyingIfaces.get(i), tunUid, SET_FOREGROUND,
+                            TAG_NONE, METERED_NO, ROAMING_NO, DEFAULT_NETWORK_NO);
+            if (idxVpnForeground != -1) {
+                tunSubtract(idxVpnForeground, this, moved[i]);
+            }
+        }
+    }
+
+    private static void tunSubtract(int i, @NonNull NetworkStats left, @NonNull Entry right) {
+        long rxBytes = Math.min(left.rxBytes[i], right.rxBytes);
+        left.rxBytes[i] -= rxBytes;
+        right.rxBytes -= rxBytes;
+
+        long rxPackets = Math.min(left.rxPackets[i], right.rxPackets);
+        left.rxPackets[i] -= rxPackets;
+        right.rxPackets -= rxPackets;
+
+        long txBytes = Math.min(left.txBytes[i], right.txBytes);
+        left.txBytes[i] -= txBytes;
+        right.txBytes -= txBytes;
+
+        long txPackets = Math.min(left.txPackets[i], right.txPackets);
+        left.txPackets[i] -= txPackets;
+        right.txPackets -= txPackets;
+    }
+}
diff --git a/framework-t/src/android/net/NetworkStatsHistory.aidl b/framework-t/src/android/net/NetworkStatsHistory.aidl
new file mode 100644
index 0000000..8b9069f
--- /dev/null
+++ b/framework-t/src/android/net/NetworkStatsHistory.aidl
@@ -0,0 +1,19 @@
+/**
+ * Copyright (c) 2011, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+parcelable NetworkStatsHistory;
diff --git a/framework-t/src/android/net/NetworkStatsHistory.java b/framework-t/src/android/net/NetworkStatsHistory.java
new file mode 100644
index 0000000..a875e1a
--- /dev/null
+++ b/framework-t/src/android/net/NetworkStatsHistory.java
@@ -0,0 +1,881 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.net.NetworkStats.IFACE_ALL;
+import static android.net.NetworkStats.SET_DEFAULT;
+import static android.net.NetworkStats.TAG_NONE;
+import static android.net.NetworkStats.UID_ALL;
+import static android.net.NetworkStatsHistory.DataStreamUtils.readFullLongArray;
+import static android.net.NetworkStatsHistory.DataStreamUtils.readVarLongArray;
+import static android.net.NetworkStatsHistory.DataStreamUtils.writeVarLongArray;
+import static android.net.NetworkStatsHistory.Entry.UNKNOWN;
+import static android.net.NetworkStatsHistory.ParcelUtils.readLongArray;
+import static android.net.NetworkStatsHistory.ParcelUtils.writeLongArray;
+import static android.text.format.DateUtils.SECOND_IN_MILLIS;
+
+import static com.android.internal.net.NetworkUtilsInternal.multiplySafeByRational;
+import static com.android.internal.util.ArrayUtils.total;
+
+import android.compat.annotation.UnsupportedAppUsage;
+import android.os.Build;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.service.NetworkStatsHistoryBucketProto;
+import android.service.NetworkStatsHistoryProto;
+import android.util.MathUtils;
+import android.util.proto.ProtoOutputStream;
+
+import com.android.internal.util.IndentingPrintWriter;
+
+import libcore.util.EmptyArray;
+
+import java.io.CharArrayWriter;
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.net.ProtocolException;
+import java.util.Arrays;
+import java.util.Random;
+
+/**
+ * Collection of historical network statistics, recorded into equally-sized
+ * "buckets" in time. Internally it stores data in {@code long} series for more
+ * efficient persistence.
+ * <p>
+ * Each bucket is defined by a {@link #bucketStart} timestamp, and lasts for
+ * {@link #bucketDuration}. Internally assumes that {@link #bucketStart} is
+ * sorted at all times.
+ *
+ * @hide
+ */
+public class NetworkStatsHistory implements Parcelable {
+    private static final int VERSION_INIT = 1;
+    private static final int VERSION_ADD_PACKETS = 2;
+    private static final int VERSION_ADD_ACTIVE = 3;
+
+    public static final int FIELD_ACTIVE_TIME = 0x01;
+    public static final int FIELD_RX_BYTES = 0x02;
+    public static final int FIELD_RX_PACKETS = 0x04;
+    public static final int FIELD_TX_BYTES = 0x08;
+    public static final int FIELD_TX_PACKETS = 0x10;
+    public static final int FIELD_OPERATIONS = 0x20;
+
+    public static final int FIELD_ALL = 0xFFFFFFFF;
+
+    private long bucketDuration;
+    private int bucketCount;
+    private long[] bucketStart;
+    private long[] activeTime;
+    private long[] rxBytes;
+    private long[] rxPackets;
+    private long[] txBytes;
+    private long[] txPackets;
+    private long[] operations;
+    private long totalBytes;
+
+    public static class Entry {
+        public static final long UNKNOWN = -1;
+
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long bucketDuration;
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long bucketStart;
+        public long activeTime;
+        @UnsupportedAppUsage
+        public long rxBytes;
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long rxPackets;
+        @UnsupportedAppUsage
+        public long txBytes;
+        @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+        public long txPackets;
+        public long operations;
+    }
+
+    @UnsupportedAppUsage
+    public NetworkStatsHistory(long bucketDuration) {
+        this(bucketDuration, 10, FIELD_ALL);
+    }
+
+    public NetworkStatsHistory(long bucketDuration, int initialSize) {
+        this(bucketDuration, initialSize, FIELD_ALL);
+    }
+
+    public NetworkStatsHistory(long bucketDuration, int initialSize, int fields) {
+        this.bucketDuration = bucketDuration;
+        bucketStart = new long[initialSize];
+        if ((fields & FIELD_ACTIVE_TIME) != 0) activeTime = new long[initialSize];
+        if ((fields & FIELD_RX_BYTES) != 0) rxBytes = new long[initialSize];
+        if ((fields & FIELD_RX_PACKETS) != 0) rxPackets = new long[initialSize];
+        if ((fields & FIELD_TX_BYTES) != 0) txBytes = new long[initialSize];
+        if ((fields & FIELD_TX_PACKETS) != 0) txPackets = new long[initialSize];
+        if ((fields & FIELD_OPERATIONS) != 0) operations = new long[initialSize];
+        bucketCount = 0;
+        totalBytes = 0;
+    }
+
+    public NetworkStatsHistory(NetworkStatsHistory existing, long bucketDuration) {
+        this(bucketDuration, existing.estimateResizeBuckets(bucketDuration));
+        recordEntireHistory(existing);
+    }
+
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public NetworkStatsHistory(Parcel in) {
+        bucketDuration = in.readLong();
+        bucketStart = readLongArray(in);
+        activeTime = readLongArray(in);
+        rxBytes = readLongArray(in);
+        rxPackets = readLongArray(in);
+        txBytes = readLongArray(in);
+        txPackets = readLongArray(in);
+        operations = readLongArray(in);
+        bucketCount = bucketStart.length;
+        totalBytes = in.readLong();
+    }
+
+    @Override
+    public void writeToParcel(Parcel out, int flags) {
+        out.writeLong(bucketDuration);
+        writeLongArray(out, bucketStart, bucketCount);
+        writeLongArray(out, activeTime, bucketCount);
+        writeLongArray(out, rxBytes, bucketCount);
+        writeLongArray(out, rxPackets, bucketCount);
+        writeLongArray(out, txBytes, bucketCount);
+        writeLongArray(out, txPackets, bucketCount);
+        writeLongArray(out, operations, bucketCount);
+        out.writeLong(totalBytes);
+    }
+
+    public NetworkStatsHistory(DataInput in) throws IOException {
+        final int version = in.readInt();
+        switch (version) {
+            case VERSION_INIT: {
+                bucketDuration = in.readLong();
+                bucketStart = readFullLongArray(in);
+                rxBytes = readFullLongArray(in);
+                rxPackets = new long[bucketStart.length];
+                txBytes = readFullLongArray(in);
+                txPackets = new long[bucketStart.length];
+                operations = new long[bucketStart.length];
+                bucketCount = bucketStart.length;
+                totalBytes = total(rxBytes) + total(txBytes);
+                break;
+            }
+            case VERSION_ADD_PACKETS:
+            case VERSION_ADD_ACTIVE: {
+                bucketDuration = in.readLong();
+                bucketStart = readVarLongArray(in);
+                activeTime = (version >= VERSION_ADD_ACTIVE) ? readVarLongArray(in)
+                        : new long[bucketStart.length];
+                rxBytes = readVarLongArray(in);
+                rxPackets = readVarLongArray(in);
+                txBytes = readVarLongArray(in);
+                txPackets = readVarLongArray(in);
+                operations = readVarLongArray(in);
+                bucketCount = bucketStart.length;
+                totalBytes = total(rxBytes) + total(txBytes);
+                break;
+            }
+            default: {
+                throw new ProtocolException("unexpected version: " + version);
+            }
+        }
+
+        if (bucketStart.length != bucketCount || rxBytes.length != bucketCount
+                || rxPackets.length != bucketCount || txBytes.length != bucketCount
+                || txPackets.length != bucketCount || operations.length != bucketCount) {
+            throw new ProtocolException("Mismatched history lengths");
+        }
+    }
+
+    public void writeToStream(DataOutput out) throws IOException {
+        out.writeInt(VERSION_ADD_ACTIVE);
+        out.writeLong(bucketDuration);
+        writeVarLongArray(out, bucketStart, bucketCount);
+        writeVarLongArray(out, activeTime, bucketCount);
+        writeVarLongArray(out, rxBytes, bucketCount);
+        writeVarLongArray(out, rxPackets, bucketCount);
+        writeVarLongArray(out, txBytes, bucketCount);
+        writeVarLongArray(out, txPackets, bucketCount);
+        writeVarLongArray(out, operations, bucketCount);
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public int size() {
+        return bucketCount;
+    }
+
+    public long getBucketDuration() {
+        return bucketDuration;
+    }
+
+    @UnsupportedAppUsage
+    public long getStart() {
+        if (bucketCount > 0) {
+            return bucketStart[0];
+        } else {
+            return Long.MAX_VALUE;
+        }
+    }
+
+    @UnsupportedAppUsage
+    public long getEnd() {
+        if (bucketCount > 0) {
+            return bucketStart[bucketCount - 1] + bucketDuration;
+        } else {
+            return Long.MIN_VALUE;
+        }
+    }
+
+    /**
+     * Return total bytes represented by this history.
+     */
+    public long getTotalBytes() {
+        return totalBytes;
+    }
+
+    /**
+     * Return index of bucket that contains or is immediately before the
+     * requested time.
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public int getIndexBefore(long time) {
+        int index = Arrays.binarySearch(bucketStart, 0, bucketCount, time);
+        if (index < 0) {
+            index = (~index) - 1;
+        } else {
+            index -= 1;
+        }
+        return MathUtils.constrain(index, 0, bucketCount - 1);
+    }
+
+    /**
+     * Return index of bucket that contains or is immediately after the
+     * requested time.
+     */
+    public int getIndexAfter(long time) {
+        int index = Arrays.binarySearch(bucketStart, 0, bucketCount, time);
+        if (index < 0) {
+            index = ~index;
+        } else {
+            index += 1;
+        }
+        return MathUtils.constrain(index, 0, bucketCount - 1);
+    }
+
+    /**
+     * Return specific stats entry.
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public Entry getValues(int i, Entry recycle) {
+        final Entry entry = recycle != null ? recycle : new Entry();
+        entry.bucketStart = bucketStart[i];
+        entry.bucketDuration = bucketDuration;
+        entry.activeTime = getLong(activeTime, i, UNKNOWN);
+        entry.rxBytes = getLong(rxBytes, i, UNKNOWN);
+        entry.rxPackets = getLong(rxPackets, i, UNKNOWN);
+        entry.txBytes = getLong(txBytes, i, UNKNOWN);
+        entry.txPackets = getLong(txPackets, i, UNKNOWN);
+        entry.operations = getLong(operations, i, UNKNOWN);
+        return entry;
+    }
+
+    public void setValues(int i, Entry entry) {
+        // Unwind old values
+        if (rxBytes != null) totalBytes -= rxBytes[i];
+        if (txBytes != null) totalBytes -= txBytes[i];
+
+        bucketStart[i] = entry.bucketStart;
+        setLong(activeTime, i, entry.activeTime);
+        setLong(rxBytes, i, entry.rxBytes);
+        setLong(rxPackets, i, entry.rxPackets);
+        setLong(txBytes, i, entry.txBytes);
+        setLong(txPackets, i, entry.txPackets);
+        setLong(operations, i, entry.operations);
+
+        // Apply new values
+        if (rxBytes != null) totalBytes += rxBytes[i];
+        if (txBytes != null) totalBytes += txBytes[i];
+    }
+
+    /**
+     * Record that data traffic occurred in the given time range. Will
+     * distribute across internal buckets, creating new buckets as needed.
+     */
+    @Deprecated
+    public void recordData(long start, long end, long rxBytes, long txBytes) {
+        recordData(start, end, new NetworkStats.Entry(
+                IFACE_ALL, UID_ALL, SET_DEFAULT, TAG_NONE, rxBytes, 0L, txBytes, 0L, 0L));
+    }
+
+    /**
+     * Record that data traffic occurred in the given time range. Will
+     * distribute across internal buckets, creating new buckets as needed.
+     */
+    public void recordData(long start, long end, NetworkStats.Entry entry) {
+        long rxBytes = entry.rxBytes;
+        long rxPackets = entry.rxPackets;
+        long txBytes = entry.txBytes;
+        long txPackets = entry.txPackets;
+        long operations = entry.operations;
+
+        if (entry.isNegative()) {
+            throw new IllegalArgumentException("tried recording negative data");
+        }
+        if (entry.isEmpty()) {
+            return;
+        }
+
+        // create any buckets needed by this range
+        ensureBuckets(start, end);
+
+        // distribute data usage into buckets
+        long duration = end - start;
+        final int startIndex = getIndexAfter(end);
+        for (int i = startIndex; i >= 0; i--) {
+            final long curStart = bucketStart[i];
+            final long curEnd = curStart + bucketDuration;
+
+            // bucket is older than record; we're finished
+            if (curEnd < start) break;
+            // bucket is newer than record; keep looking
+            if (curStart > end) continue;
+
+            final long overlap = Math.min(curEnd, end) - Math.max(curStart, start);
+            if (overlap <= 0) continue;
+
+            // integer math each time is faster than floating point
+            final long fracRxBytes = multiplySafeByRational(rxBytes, overlap, duration);
+            final long fracRxPackets = multiplySafeByRational(rxPackets, overlap, duration);
+            final long fracTxBytes = multiplySafeByRational(txBytes, overlap, duration);
+            final long fracTxPackets = multiplySafeByRational(txPackets, overlap, duration);
+            final long fracOperations = multiplySafeByRational(operations, overlap, duration);
+
+
+            addLong(activeTime, i, overlap);
+            addLong(this.rxBytes, i, fracRxBytes); rxBytes -= fracRxBytes;
+            addLong(this.rxPackets, i, fracRxPackets); rxPackets -= fracRxPackets;
+            addLong(this.txBytes, i, fracTxBytes); txBytes -= fracTxBytes;
+            addLong(this.txPackets, i, fracTxPackets); txPackets -= fracTxPackets;
+            addLong(this.operations, i, fracOperations); operations -= fracOperations;
+
+            duration -= overlap;
+        }
+
+        totalBytes += entry.rxBytes + entry.txBytes;
+    }
+
+    /**
+     * Record an entire {@link NetworkStatsHistory} into this history. Usually
+     * for combining together stats for external reporting.
+     */
+    @UnsupportedAppUsage
+    public void recordEntireHistory(NetworkStatsHistory input) {
+        recordHistory(input, Long.MIN_VALUE, Long.MAX_VALUE);
+    }
+
+    /**
+     * Record given {@link NetworkStatsHistory} into this history, copying only
+     * buckets that atomically occur in the inclusive time range. Doesn't
+     * interpolate across partial buckets.
+     */
+    public void recordHistory(NetworkStatsHistory input, long start, long end) {
+        final NetworkStats.Entry entry = new NetworkStats.Entry(
+                IFACE_ALL, UID_ALL, SET_DEFAULT, TAG_NONE, 0L, 0L, 0L, 0L, 0L);
+        for (int i = 0; i < input.bucketCount; i++) {
+            final long bucketStart = input.bucketStart[i];
+            final long bucketEnd = bucketStart + input.bucketDuration;
+
+            // skip when bucket is outside requested range
+            if (bucketStart < start || bucketEnd > end) continue;
+
+            entry.rxBytes = getLong(input.rxBytes, i, 0L);
+            entry.rxPackets = getLong(input.rxPackets, i, 0L);
+            entry.txBytes = getLong(input.txBytes, i, 0L);
+            entry.txPackets = getLong(input.txPackets, i, 0L);
+            entry.operations = getLong(input.operations, i, 0L);
+
+            recordData(bucketStart, bucketEnd, entry);
+        }
+    }
+
+    /**
+     * Ensure that buckets exist for given time range, creating as needed.
+     */
+    private void ensureBuckets(long start, long end) {
+        // normalize incoming range to bucket boundaries
+        start -= start % bucketDuration;
+        end += (bucketDuration - (end % bucketDuration)) % bucketDuration;
+
+        for (long now = start; now < end; now += bucketDuration) {
+            // try finding existing bucket
+            final int index = Arrays.binarySearch(bucketStart, 0, bucketCount, now);
+            if (index < 0) {
+                // bucket missing, create and insert
+                insertBucket(~index, now);
+            }
+        }
+    }
+
+    /**
+     * Insert new bucket at requested index and starting time.
+     */
+    private void insertBucket(int index, long start) {
+        // create more buckets when needed
+        if (bucketCount >= bucketStart.length) {
+            final int newLength = Math.max(bucketStart.length, 10) * 3 / 2;
+            bucketStart = Arrays.copyOf(bucketStart, newLength);
+            if (activeTime != null) activeTime = Arrays.copyOf(activeTime, newLength);
+            if (rxBytes != null) rxBytes = Arrays.copyOf(rxBytes, newLength);
+            if (rxPackets != null) rxPackets = Arrays.copyOf(rxPackets, newLength);
+            if (txBytes != null) txBytes = Arrays.copyOf(txBytes, newLength);
+            if (txPackets != null) txPackets = Arrays.copyOf(txPackets, newLength);
+            if (operations != null) operations = Arrays.copyOf(operations, newLength);
+        }
+
+        // create gap when inserting bucket in middle
+        if (index < bucketCount) {
+            final int dstPos = index + 1;
+            final int length = bucketCount - index;
+
+            System.arraycopy(bucketStart, index, bucketStart, dstPos, length);
+            if (activeTime != null) System.arraycopy(activeTime, index, activeTime, dstPos, length);
+            if (rxBytes != null) System.arraycopy(rxBytes, index, rxBytes, dstPos, length);
+            if (rxPackets != null) System.arraycopy(rxPackets, index, rxPackets, dstPos, length);
+            if (txBytes != null) System.arraycopy(txBytes, index, txBytes, dstPos, length);
+            if (txPackets != null) System.arraycopy(txPackets, index, txPackets, dstPos, length);
+            if (operations != null) System.arraycopy(operations, index, operations, dstPos, length);
+        }
+
+        bucketStart[index] = start;
+        setLong(activeTime, index, 0L);
+        setLong(rxBytes, index, 0L);
+        setLong(rxPackets, index, 0L);
+        setLong(txBytes, index, 0L);
+        setLong(txPackets, index, 0L);
+        setLong(operations, index, 0L);
+        bucketCount++;
+    }
+
+    /**
+     * Clear all data stored in this object.
+     */
+    public void clear() {
+        bucketStart = EmptyArray.LONG;
+        if (activeTime != null) activeTime = EmptyArray.LONG;
+        if (rxBytes != null) rxBytes = EmptyArray.LONG;
+        if (rxPackets != null) rxPackets = EmptyArray.LONG;
+        if (txBytes != null) txBytes = EmptyArray.LONG;
+        if (txPackets != null) txPackets = EmptyArray.LONG;
+        if (operations != null) operations = EmptyArray.LONG;
+        bucketCount = 0;
+        totalBytes = 0;
+    }
+
+    /**
+     * Remove buckets older than requested cutoff.
+     */
+    @Deprecated
+    public void removeBucketsBefore(long cutoff) {
+        int i;
+        for (i = 0; i < bucketCount; i++) {
+            final long curStart = bucketStart[i];
+            final long curEnd = curStart + bucketDuration;
+
+            // cutoff happens before or during this bucket; everything before
+            // this bucket should be removed.
+            if (curEnd > cutoff) break;
+        }
+
+        if (i > 0) {
+            final int length = bucketStart.length;
+            bucketStart = Arrays.copyOfRange(bucketStart, i, length);
+            if (activeTime != null) activeTime = Arrays.copyOfRange(activeTime, i, length);
+            if (rxBytes != null) rxBytes = Arrays.copyOfRange(rxBytes, i, length);
+            if (rxPackets != null) rxPackets = Arrays.copyOfRange(rxPackets, i, length);
+            if (txBytes != null) txBytes = Arrays.copyOfRange(txBytes, i, length);
+            if (txPackets != null) txPackets = Arrays.copyOfRange(txPackets, i, length);
+            if (operations != null) operations = Arrays.copyOfRange(operations, i, length);
+            bucketCount -= i;
+
+            // TODO: subtract removed values from totalBytes
+        }
+    }
+
+    /**
+     * Return interpolated data usage across the requested range. Interpolates
+     * across buckets, so values may be rounded slightly.
+     *
+     * <p>If the active bucket is not completed yet, it returns the proportional value of it
+     * based on its duration and the {@code end} param.
+     *
+     * @param start - start of the range, timestamp in milliseconds since the epoch.
+     * @param end - end of the range, timestamp in milliseconds since the epoch.
+     * @param recycle - entry instance for performance, could be null.
+     */
+    @UnsupportedAppUsage
+    public Entry getValues(long start, long end, Entry recycle) {
+        return getValues(start, end, Long.MAX_VALUE, recycle);
+    }
+
+    /**
+     * Return interpolated data usage across the requested range. Interpolates
+     * across buckets, so values may be rounded slightly.
+     *
+     * @param start - start of the range, timestamp in milliseconds since the epoch.
+     * @param end - end of the range, timestamp in milliseconds since the epoch.
+     * @param now - current timestamp in milliseconds since the epoch (wall clock).
+     * @param recycle - entry instance for performance, could be null.
+     */
+    @UnsupportedAppUsage
+    public Entry getValues(long start, long end, long now, Entry recycle) {
+        final Entry entry = recycle != null ? recycle : new Entry();
+        entry.bucketDuration = end - start;
+        entry.bucketStart = start;
+        entry.activeTime = activeTime != null ? 0 : UNKNOWN;
+        entry.rxBytes = rxBytes != null ? 0 : UNKNOWN;
+        entry.rxPackets = rxPackets != null ? 0 : UNKNOWN;
+        entry.txBytes = txBytes != null ? 0 : UNKNOWN;
+        entry.txPackets = txPackets != null ? 0 : UNKNOWN;
+        entry.operations = operations != null ? 0 : UNKNOWN;
+
+        final int startIndex = getIndexAfter(end);
+        for (int i = startIndex; i >= 0; i--) {
+            final long curStart = bucketStart[i];
+            long curEnd = curStart + bucketDuration;
+
+            // bucket is older than request; we're finished
+            if (curEnd <= start) break;
+            // bucket is newer than request; keep looking
+            if (curStart >= end) continue;
+
+            // the active bucket is shorter then a normal completed bucket
+            if (curEnd > now) curEnd = now;
+            // usually this is simply bucketDuration
+            final long bucketSpan = curEnd - curStart;
+            // prevent division by zero
+            if (bucketSpan <= 0) continue;
+
+            final long overlapEnd = curEnd < end ? curEnd : end;
+            final long overlapStart = curStart > start ? curStart : start;
+            final long overlap = overlapEnd - overlapStart;
+            if (overlap <= 0) continue;
+
+            // integer math each time is faster than floating point
+            if (activeTime != null) {
+                entry.activeTime += multiplySafeByRational(activeTime[i], overlap, bucketSpan);
+            }
+            if (rxBytes != null) {
+                entry.rxBytes += multiplySafeByRational(rxBytes[i], overlap, bucketSpan);
+            }
+            if (rxPackets != null) {
+                entry.rxPackets += multiplySafeByRational(rxPackets[i], overlap, bucketSpan);
+            }
+            if (txBytes != null) {
+                entry.txBytes += multiplySafeByRational(txBytes[i], overlap, bucketSpan);
+            }
+            if (txPackets != null) {
+                entry.txPackets += multiplySafeByRational(txPackets[i], overlap, bucketSpan);
+            }
+            if (operations != null) {
+                entry.operations += multiplySafeByRational(operations[i], overlap, bucketSpan);
+            }
+        }
+        return entry;
+    }
+
+    /**
+     * @deprecated only for temporary testing
+     */
+    @Deprecated
+    public void generateRandom(long start, long end, long bytes) {
+        final Random r = new Random();
+
+        final float fractionRx = r.nextFloat();
+        final long rxBytes = (long) (bytes * fractionRx);
+        final long txBytes = (long) (bytes * (1 - fractionRx));
+
+        final long rxPackets = rxBytes / 1024;
+        final long txPackets = txBytes / 1024;
+        final long operations = rxBytes / 2048;
+
+        generateRandom(start, end, rxBytes, rxPackets, txBytes, txPackets, operations, r);
+    }
+
+    /**
+     * @deprecated only for temporary testing
+     */
+    @Deprecated
+    public void generateRandom(long start, long end, long rxBytes, long rxPackets, long txBytes,
+            long txPackets, long operations, Random r) {
+        ensureBuckets(start, end);
+
+        final NetworkStats.Entry entry = new NetworkStats.Entry(
+                IFACE_ALL, UID_ALL, SET_DEFAULT, TAG_NONE, 0L, 0L, 0L, 0L, 0L);
+        while (rxBytes > 1024 || rxPackets > 128 || txBytes > 1024 || txPackets > 128
+                || operations > 32) {
+            final long curStart = randomLong(r, start, end);
+            final long curEnd = curStart + randomLong(r, 0, (end - curStart) / 2);
+
+            entry.rxBytes = randomLong(r, 0, rxBytes);
+            entry.rxPackets = randomLong(r, 0, rxPackets);
+            entry.txBytes = randomLong(r, 0, txBytes);
+            entry.txPackets = randomLong(r, 0, txPackets);
+            entry.operations = randomLong(r, 0, operations);
+
+            rxBytes -= entry.rxBytes;
+            rxPackets -= entry.rxPackets;
+            txBytes -= entry.txBytes;
+            txPackets -= entry.txPackets;
+            operations -= entry.operations;
+
+            recordData(curStart, curEnd, entry);
+        }
+    }
+
+    public static long randomLong(Random r, long start, long end) {
+        return (long) (start + (r.nextFloat() * (end - start)));
+    }
+
+    /**
+     * Quickly determine if this history intersects with given window.
+     */
+    public boolean intersects(long start, long end) {
+        final long dataStart = getStart();
+        final long dataEnd = getEnd();
+        if (start >= dataStart && start <= dataEnd) return true;
+        if (end >= dataStart && end <= dataEnd) return true;
+        if (dataStart >= start && dataStart <= end) return true;
+        if (dataEnd >= start && dataEnd <= end) return true;
+        return false;
+    }
+
+    public void dump(IndentingPrintWriter pw, boolean fullHistory) {
+        pw.print("NetworkStatsHistory: bucketDuration=");
+        pw.println(bucketDuration / SECOND_IN_MILLIS);
+        pw.increaseIndent();
+
+        final int start = fullHistory ? 0 : Math.max(0, bucketCount - 32);
+        if (start > 0) {
+            pw.print("(omitting "); pw.print(start); pw.println(" buckets)");
+        }
+
+        for (int i = start; i < bucketCount; i++) {
+            pw.print("st="); pw.print(bucketStart[i] / SECOND_IN_MILLIS);
+            if (rxBytes != null) { pw.print(" rb="); pw.print(rxBytes[i]); }
+            if (rxPackets != null) { pw.print(" rp="); pw.print(rxPackets[i]); }
+            if (txBytes != null) { pw.print(" tb="); pw.print(txBytes[i]); }
+            if (txPackets != null) { pw.print(" tp="); pw.print(txPackets[i]); }
+            if (operations != null) { pw.print(" op="); pw.print(operations[i]); }
+            pw.println();
+        }
+
+        pw.decreaseIndent();
+    }
+
+    public void dumpCheckin(PrintWriter pw) {
+        pw.print("d,");
+        pw.print(bucketDuration / SECOND_IN_MILLIS);
+        pw.println();
+
+        for (int i = 0; i < bucketCount; i++) {
+            pw.print("b,");
+            pw.print(bucketStart[i] / SECOND_IN_MILLIS); pw.print(',');
+            if (rxBytes != null) { pw.print(rxBytes[i]); } else { pw.print("*"); } pw.print(',');
+            if (rxPackets != null) { pw.print(rxPackets[i]); } else { pw.print("*"); } pw.print(',');
+            if (txBytes != null) { pw.print(txBytes[i]); } else { pw.print("*"); } pw.print(',');
+            if (txPackets != null) { pw.print(txPackets[i]); } else { pw.print("*"); } pw.print(',');
+            if (operations != null) { pw.print(operations[i]); } else { pw.print("*"); }
+            pw.println();
+        }
+    }
+
+    public void dumpDebug(ProtoOutputStream proto, long tag) {
+        final long start = proto.start(tag);
+
+        proto.write(NetworkStatsHistoryProto.BUCKET_DURATION_MS, bucketDuration);
+
+        for (int i = 0; i < bucketCount; i++) {
+            final long startBucket = proto.start(NetworkStatsHistoryProto.BUCKETS);
+
+            proto.write(NetworkStatsHistoryBucketProto.BUCKET_START_MS, bucketStart[i]);
+            dumpDebug(proto, NetworkStatsHistoryBucketProto.RX_BYTES, rxBytes, i);
+            dumpDebug(proto, NetworkStatsHistoryBucketProto.RX_PACKETS, rxPackets, i);
+            dumpDebug(proto, NetworkStatsHistoryBucketProto.TX_BYTES, txBytes, i);
+            dumpDebug(proto, NetworkStatsHistoryBucketProto.TX_PACKETS, txPackets, i);
+            dumpDebug(proto, NetworkStatsHistoryBucketProto.OPERATIONS, operations, i);
+
+            proto.end(startBucket);
+        }
+
+        proto.end(start);
+    }
+
+    private static void dumpDebug(ProtoOutputStream proto, long tag, long[] array, int index) {
+        if (array != null) {
+            proto.write(tag, array[index]);
+        }
+    }
+
+    @Override
+    public String toString() {
+        final CharArrayWriter writer = new CharArrayWriter();
+        dump(new IndentingPrintWriter(writer, "  "), false);
+        return writer.toString();
+    }
+
+    @UnsupportedAppUsage
+    public static final @android.annotation.NonNull Creator<NetworkStatsHistory> CREATOR = new Creator<NetworkStatsHistory>() {
+        @Override
+        public NetworkStatsHistory createFromParcel(Parcel in) {
+            return new NetworkStatsHistory(in);
+        }
+
+        @Override
+        public NetworkStatsHistory[] newArray(int size) {
+            return new NetworkStatsHistory[size];
+        }
+    };
+
+    private static long getLong(long[] array, int i, long value) {
+        return array != null ? array[i] : value;
+    }
+
+    private static void setLong(long[] array, int i, long value) {
+        if (array != null) array[i] = value;
+    }
+
+    private static void addLong(long[] array, int i, long value) {
+        if (array != null) array[i] += value;
+    }
+
+    public int estimateResizeBuckets(long newBucketDuration) {
+        return (int) (size() * getBucketDuration() / newBucketDuration);
+    }
+
+    /**
+     * Utility methods for interacting with {@link DataInputStream} and
+     * {@link DataOutputStream}, mostly dealing with writing partial arrays.
+     */
+    public static class DataStreamUtils {
+        @Deprecated
+        public static long[] readFullLongArray(DataInput in) throws IOException {
+            final int size = in.readInt();
+            if (size < 0) throw new ProtocolException("negative array size");
+            final long[] values = new long[size];
+            for (int i = 0; i < values.length; i++) {
+                values[i] = in.readLong();
+            }
+            return values;
+        }
+
+        /**
+         * Read variable-length {@link Long} using protobuf-style approach.
+         */
+        public static long readVarLong(DataInput in) throws IOException {
+            int shift = 0;
+            long result = 0;
+            while (shift < 64) {
+                byte b = in.readByte();
+                result |= (long) (b & 0x7F) << shift;
+                if ((b & 0x80) == 0)
+                    return result;
+                shift += 7;
+            }
+            throw new ProtocolException("malformed long");
+        }
+
+        /**
+         * Write variable-length {@link Long} using protobuf-style approach.
+         */
+        public static void writeVarLong(DataOutput out, long value) throws IOException {
+            while (true) {
+                if ((value & ~0x7FL) == 0) {
+                    out.writeByte((int) value);
+                    return;
+                } else {
+                    out.writeByte(((int) value & 0x7F) | 0x80);
+                    value >>>= 7;
+                }
+            }
+        }
+
+        public static long[] readVarLongArray(DataInput in) throws IOException {
+            final int size = in.readInt();
+            if (size == -1) return null;
+            if (size < 0) throw new ProtocolException("negative array size");
+            final long[] values = new long[size];
+            for (int i = 0; i < values.length; i++) {
+                values[i] = readVarLong(in);
+            }
+            return values;
+        }
+
+        public static void writeVarLongArray(DataOutput out, long[] values, int size)
+                throws IOException {
+            if (values == null) {
+                out.writeInt(-1);
+                return;
+            }
+            if (size > values.length) {
+                throw new IllegalArgumentException("size larger than length");
+            }
+            out.writeInt(size);
+            for (int i = 0; i < size; i++) {
+                writeVarLong(out, values[i]);
+            }
+        }
+    }
+
+    /**
+     * Utility methods for interacting with {@link Parcel} structures, mostly
+     * dealing with writing partial arrays.
+     */
+    public static class ParcelUtils {
+        public static long[] readLongArray(Parcel in) {
+            final int size = in.readInt();
+            if (size == -1) return null;
+            final long[] values = new long[size];
+            for (int i = 0; i < values.length; i++) {
+                values[i] = in.readLong();
+            }
+            return values;
+        }
+
+        public static void writeLongArray(Parcel out, long[] values, int size) {
+            if (values == null) {
+                out.writeInt(-1);
+                return;
+            }
+            if (size > values.length) {
+                throw new IllegalArgumentException("size larger than length");
+            }
+            out.writeInt(size);
+            for (int i = 0; i < size; i++) {
+                out.writeLong(values[i]);
+            }
+        }
+    }
+
+}
diff --git a/framework-t/src/android/net/NetworkTemplate.java b/framework-t/src/android/net/NetworkTemplate.java
new file mode 100644
index 0000000..c906a13
--- /dev/null
+++ b/framework-t/src/android/net/NetworkTemplate.java
@@ -0,0 +1,906 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.net.ConnectivityManager.TYPE_BLUETOOTH;
+import static android.net.ConnectivityManager.TYPE_ETHERNET;
+import static android.net.ConnectivityManager.TYPE_MOBILE;
+import static android.net.ConnectivityManager.TYPE_PROXY;
+import static android.net.ConnectivityManager.TYPE_WIFI;
+import static android.net.ConnectivityManager.TYPE_WIFI_P2P;
+import static android.net.ConnectivityManager.TYPE_WIMAX;
+import static android.net.NetworkIdentity.OEM_NONE;
+import static android.net.NetworkStats.DEFAULT_NETWORK_ALL;
+import static android.net.NetworkStats.DEFAULT_NETWORK_NO;
+import static android.net.NetworkStats.DEFAULT_NETWORK_YES;
+import static android.net.NetworkStats.METERED_ALL;
+import static android.net.NetworkStats.METERED_NO;
+import static android.net.NetworkStats.METERED_YES;
+import static android.net.NetworkStats.ROAMING_ALL;
+import static android.net.NetworkStats.ROAMING_NO;
+import static android.net.NetworkStats.ROAMING_YES;
+import static android.net.wifi.WifiInfo.sanitizeSsid;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.compat.annotation.UnsupportedAppUsage;
+import android.os.Build;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.telephony.Annotation.NetworkType;
+import android.telephony.TelephonyManager;
+import android.text.TextUtils;
+import android.util.BackupUtils;
+import android.util.Log;
+
+import com.android.internal.util.ArrayUtils;
+import com.android.net.module.util.NetworkIdentityUtils;
+
+import java.io.ByteArrayOutputStream;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * Predicate used to match {@link NetworkIdentity}, usually when collecting
+ * statistics. (It should probably have been named {@code NetworkPredicate}.)
+ *
+ * @hide
+ */
+public class NetworkTemplate implements Parcelable {
+    private static final String TAG = "NetworkTemplate";
+
+    /**
+     * Initial Version of the backup serializer.
+     */
+    public static final int BACKUP_VERSION_1_INIT = 1;
+    /**
+     * Version of the backup serializer that added carrier template support.
+     */
+    public static final int BACKUP_VERSION_2_SUPPORT_CARRIER_TEMPLATE = 2;
+    /**
+     * Current Version of the Backup Serializer.
+     */
+    private static final int BACKUP_VERSION = BACKUP_VERSION_2_SUPPORT_CARRIER_TEMPLATE;
+
+    public static final int MATCH_MOBILE = 1;
+    public static final int MATCH_WIFI = 4;
+    public static final int MATCH_ETHERNET = 5;
+    public static final int MATCH_MOBILE_WILDCARD = 6;
+    public static final int MATCH_WIFI_WILDCARD = 7;
+    public static final int MATCH_BLUETOOTH = 8;
+    public static final int MATCH_PROXY = 9;
+    public static final int MATCH_CARRIER = 10;
+
+    /**
+     * Value of the match rule of the subscriberId to match networks with specific subscriberId.
+     */
+    public static final int SUBSCRIBER_ID_MATCH_RULE_EXACT = 0;
+    /**
+     * Value of the match rule of the subscriberId to match networks with any subscriberId which
+     * includes null and non-null.
+     */
+    public static final int SUBSCRIBER_ID_MATCH_RULE_ALL = 1;
+
+    /**
+     * Wi-Fi Network ID is never supposed to be null (if it is, it is a bug that
+     * should be fixed), so it's not possible to want to match null vs
+     * non-null. Therefore it's fine to use null as a sentinel for Network ID.
+     */
+    public static final String WIFI_NETWORKID_ALL = null;
+
+    /**
+     * Include all network types when filtering. This is meant to merge in with the
+     * {@code TelephonyManager.NETWORK_TYPE_*} constants, and thus needs to stay in sync.
+     *
+     * @hide
+     */
+    public static final int NETWORK_TYPE_ALL = -1;
+    /**
+     * Virtual RAT type to represent 5G NSA (Non Stand Alone) mode, where the primary cell is
+     * still LTE and network allocates a secondary 5G cell so telephony reports RAT = LTE along
+     * with NR state as connected. This should not be overlapped with any of the
+     * {@code TelephonyManager.NETWORK_TYPE_*} constants.
+     *
+     * @hide
+     */
+    public static final int NETWORK_TYPE_5G_NSA = -2;
+
+    /**
+     * Value to match both OEM managed and unmanaged networks (all networks).
+     * @hide
+     */
+    public static final int OEM_MANAGED_ALL = -1;
+    /**
+     * Value to match networks which are not OEM managed.
+     * @hide
+     */
+    public static final int OEM_MANAGED_NO = OEM_NONE;
+    /**
+     * Value to match any OEM managed network.
+     * @hide
+     */
+    public static final int OEM_MANAGED_YES = -2;
+
+    private static boolean isKnownMatchRule(final int rule) {
+        switch (rule) {
+            case MATCH_MOBILE:
+            case MATCH_WIFI:
+            case MATCH_ETHERNET:
+            case MATCH_MOBILE_WILDCARD:
+            case MATCH_WIFI_WILDCARD:
+            case MATCH_BLUETOOTH:
+            case MATCH_PROXY:
+            case MATCH_CARRIER:
+                return true;
+
+            default:
+                return false;
+        }
+    }
+
+    /**
+     * Template to match {@link ConnectivityManager#TYPE_MOBILE} networks with
+     * the given IMSI.
+     */
+    @UnsupportedAppUsage
+    public static NetworkTemplate buildTemplateMobileAll(String subscriberId) {
+        return new NetworkTemplate(MATCH_MOBILE, subscriberId, null);
+    }
+
+    /**
+     * Template to match cellular networks with the given IMSI, {@code ratType} and
+     * {@code metered}. Use {@link #NETWORK_TYPE_ALL} to include all network types when
+     * filtering. See {@code TelephonyManager.NETWORK_TYPE_*}.
+     */
+    public static NetworkTemplate buildTemplateMobileWithRatType(@Nullable String subscriberId,
+            @NetworkType int ratType, int metered) {
+        if (TextUtils.isEmpty(subscriberId)) {
+            return new NetworkTemplate(MATCH_MOBILE_WILDCARD, null, null, null,
+                    metered, ROAMING_ALL, DEFAULT_NETWORK_ALL, ratType, OEM_MANAGED_ALL,
+                    SUBSCRIBER_ID_MATCH_RULE_EXACT);
+        }
+        return new NetworkTemplate(MATCH_MOBILE, subscriberId, new String[]{subscriberId}, null,
+                metered, ROAMING_ALL, DEFAULT_NETWORK_ALL, ratType, OEM_MANAGED_ALL,
+                SUBSCRIBER_ID_MATCH_RULE_EXACT);
+    }
+
+    /**
+     * Template to match metered {@link ConnectivityManager#TYPE_MOBILE} networks,
+     * regardless of IMSI.
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public static NetworkTemplate buildTemplateMobileWildcard() {
+        return new NetworkTemplate(MATCH_MOBILE_WILDCARD, null, null);
+    }
+
+    /**
+     * Template to match all metered {@link ConnectivityManager#TYPE_WIFI} networks,
+     * regardless of SSID.
+     */
+    @UnsupportedAppUsage
+    public static NetworkTemplate buildTemplateWifiWildcard() {
+        // TODO: Consider replace this with MATCH_WIFI with NETWORK_ID_ALL
+        // and SUBSCRIBER_ID_MATCH_RULE_ALL.
+        return new NetworkTemplate(MATCH_WIFI_WILDCARD, null, null);
+    }
+
+    @Deprecated
+    @UnsupportedAppUsage
+    public static NetworkTemplate buildTemplateWifi() {
+        return buildTemplateWifiWildcard();
+    }
+
+    /**
+     * Template to match {@link ConnectivityManager#TYPE_WIFI} networks with the
+     * given SSID.
+     */
+    public static NetworkTemplate buildTemplateWifi(@NonNull String networkId) {
+        Objects.requireNonNull(networkId);
+        return new NetworkTemplate(MATCH_WIFI, null /* subscriberId */,
+                new String[] { null } /* matchSubscriberIds */,
+                networkId, METERED_ALL, ROAMING_ALL,
+                DEFAULT_NETWORK_ALL, NETWORK_TYPE_ALL, OEM_MANAGED_ALL,
+                SUBSCRIBER_ID_MATCH_RULE_ALL);
+    }
+
+    /**
+     * Template to match all {@link ConnectivityManager#TYPE_WIFI} networks with the given SSID,
+     * and IMSI.
+     *
+     * Call with {@link #WIFI_NETWORKID_ALL} for {@code networkId} to get result regardless of SSID.
+     */
+    public static NetworkTemplate buildTemplateWifi(@Nullable String networkId,
+            @Nullable String subscriberId) {
+        return new NetworkTemplate(MATCH_WIFI, subscriberId, new String[] { subscriberId },
+                networkId, METERED_ALL, ROAMING_ALL,
+                DEFAULT_NETWORK_ALL, NETWORK_TYPE_ALL, OEM_MANAGED_ALL,
+                SUBSCRIBER_ID_MATCH_RULE_EXACT);
+    }
+
+    /**
+     * Template to combine all {@link ConnectivityManager#TYPE_ETHERNET} style
+     * networks together.
+     */
+    @UnsupportedAppUsage
+    public static NetworkTemplate buildTemplateEthernet() {
+        return new NetworkTemplate(MATCH_ETHERNET, null, null);
+    }
+
+    /**
+     * Template to combine all {@link ConnectivityManager#TYPE_BLUETOOTH} style
+     * networks together.
+     */
+    public static NetworkTemplate buildTemplateBluetooth() {
+        return new NetworkTemplate(MATCH_BLUETOOTH, null, null);
+    }
+
+    /**
+     * Template to combine all {@link ConnectivityManager#TYPE_PROXY} style
+     * networks together.
+     */
+    public static NetworkTemplate buildTemplateProxy() {
+        return new NetworkTemplate(MATCH_PROXY, null, null);
+    }
+
+    /**
+     * Template to match all metered carrier networks with the given IMSI.
+     */
+    public static NetworkTemplate buildTemplateCarrierMetered(@NonNull String subscriberId) {
+        Objects.requireNonNull(subscriberId);
+        return new NetworkTemplate(MATCH_CARRIER, subscriberId,
+                new String[] { subscriberId }, null /* networkId */, METERED_YES, ROAMING_ALL,
+                DEFAULT_NETWORK_ALL, NETWORK_TYPE_ALL, OEM_MANAGED_ALL,
+                SUBSCRIBER_ID_MATCH_RULE_EXACT);
+    }
+
+    private final int mMatchRule;
+    private final String mSubscriberId;
+
+    /**
+     * Ugh, templates are designed to target a single subscriber, but we might
+     * need to match several "merged" subscribers. These are the subscribers
+     * that should be considered to match this template.
+     * <p>
+     * Since the merge set is dynamic, it should <em>not</em> be persisted or
+     * used for determining equality.
+     */
+    private final String[] mMatchSubscriberIds;
+
+    private final String mNetworkId;
+
+    // Matches for the NetworkStats constants METERED_*, ROAMING_* and DEFAULT_NETWORK_*.
+    private final int mMetered;
+    private final int mRoaming;
+    private final int mDefaultNetwork;
+    private final int mSubType;
+    /**
+     * The subscriber Id match rule defines how the template should match networks with
+     * specific subscriberId(s). See NetworkTemplate#SUBSCRIBER_ID_MATCH_RULE_* for more detail.
+     */
+    private final int mSubscriberIdMatchRule;
+
+    // Bitfield containing OEM network properties{@code NetworkIdentity#OEM_*}.
+    private final int mOemManaged;
+
+    private void checkValidSubscriberIdMatchRule() {
+        switch (mMatchRule) {
+            case MATCH_MOBILE:
+            case MATCH_CARRIER:
+                // MOBILE and CARRIER templates must always specify a subscriber ID.
+                if (mSubscriberIdMatchRule == SUBSCRIBER_ID_MATCH_RULE_ALL) {
+                    throw new IllegalArgumentException("Invalid SubscriberIdMatchRule"
+                            + "on match rule: " + getMatchRuleName(mMatchRule));
+                }
+                return;
+            default:
+                return;
+        }
+    }
+
+    // TODO: Deprecate this constructor, mark it @UnsupportedAppUsage(maxTargetSdk = S)
+    @UnsupportedAppUsage
+    public NetworkTemplate(int matchRule, String subscriberId, String networkId) {
+        this(matchRule, subscriberId, new String[] { subscriberId }, networkId);
+    }
+
+    public NetworkTemplate(int matchRule, String subscriberId, String[] matchSubscriberIds,
+            String networkId) {
+        // Older versions used to only match MATCH_MOBILE and MATCH_MOBILE_WILDCARD templates
+        // to metered networks. It is now possible to match mobile with any meteredness, but
+        // in order to preserve backward compatibility of @UnsupportedAppUsage methods, this
+        //constructor passes METERED_YES for these types.
+        this(matchRule, subscriberId, matchSubscriberIds, networkId,
+                (matchRule == MATCH_MOBILE || matchRule == MATCH_MOBILE_WILDCARD) ? METERED_YES
+                : METERED_ALL , ROAMING_ALL, DEFAULT_NETWORK_ALL, NETWORK_TYPE_ALL,
+                OEM_MANAGED_ALL, SUBSCRIBER_ID_MATCH_RULE_EXACT);
+    }
+
+    // TODO: Remove it after updating all of the caller.
+    public NetworkTemplate(int matchRule, String subscriberId, String[] matchSubscriberIds,
+            String networkId, int metered, int roaming, int defaultNetwork, int subType,
+            int oemManaged) {
+        this(matchRule, subscriberId, matchSubscriberIds, networkId, metered, roaming,
+                defaultNetwork, subType, oemManaged, SUBSCRIBER_ID_MATCH_RULE_EXACT);
+    }
+
+    public NetworkTemplate(int matchRule, String subscriberId, String[] matchSubscriberIds,
+            String networkId, int metered, int roaming, int defaultNetwork, int subType,
+            int oemManaged, int subscriberIdMatchRule) {
+        mMatchRule = matchRule;
+        mSubscriberId = subscriberId;
+        // TODO: Check whether mMatchSubscriberIds = null or mMatchSubscriberIds = {null} when
+        // mSubscriberId is null
+        mMatchSubscriberIds = matchSubscriberIds;
+        mNetworkId = networkId;
+        mMetered = metered;
+        mRoaming = roaming;
+        mDefaultNetwork = defaultNetwork;
+        mSubType = subType;
+        mOemManaged = oemManaged;
+        mSubscriberIdMatchRule = subscriberIdMatchRule;
+        checkValidSubscriberIdMatchRule();
+        if (!isKnownMatchRule(matchRule)) {
+            throw new IllegalArgumentException("Unknown network template rule " + matchRule
+                    + " will not match any identity.");
+        }
+    }
+
+    private NetworkTemplate(Parcel in) {
+        mMatchRule = in.readInt();
+        mSubscriberId = in.readString();
+        mMatchSubscriberIds = in.createStringArray();
+        mNetworkId = in.readString();
+        mMetered = in.readInt();
+        mRoaming = in.readInt();
+        mDefaultNetwork = in.readInt();
+        mSubType = in.readInt();
+        mOemManaged = in.readInt();
+        mSubscriberIdMatchRule = in.readInt();
+    }
+
+    @Override
+    public void writeToParcel(Parcel dest, int flags) {
+        dest.writeInt(mMatchRule);
+        dest.writeString(mSubscriberId);
+        dest.writeStringArray(mMatchSubscriberIds);
+        dest.writeString(mNetworkId);
+        dest.writeInt(mMetered);
+        dest.writeInt(mRoaming);
+        dest.writeInt(mDefaultNetwork);
+        dest.writeInt(mSubType);
+        dest.writeInt(mOemManaged);
+        dest.writeInt(mSubscriberIdMatchRule);
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public String toString() {
+        final StringBuilder builder = new StringBuilder("NetworkTemplate: ");
+        builder.append("matchRule=").append(getMatchRuleName(mMatchRule));
+        if (mSubscriberId != null) {
+            builder.append(", subscriberId=").append(
+                    NetworkIdentityUtils.scrubSubscriberId(mSubscriberId));
+        }
+        if (mMatchSubscriberIds != null) {
+            builder.append(", matchSubscriberIds=").append(
+                    Arrays.toString(NetworkIdentityUtils.scrubSubscriberIds(mMatchSubscriberIds)));
+        }
+        if (mNetworkId != null) {
+            builder.append(", networkId=").append(mNetworkId);
+        }
+        if (mMetered != METERED_ALL) {
+            builder.append(", metered=").append(NetworkStats.meteredToString(mMetered));
+        }
+        if (mRoaming != ROAMING_ALL) {
+            builder.append(", roaming=").append(NetworkStats.roamingToString(mRoaming));
+        }
+        if (mDefaultNetwork != DEFAULT_NETWORK_ALL) {
+            builder.append(", defaultNetwork=").append(NetworkStats.defaultNetworkToString(
+                    mDefaultNetwork));
+        }
+        if (mSubType != NETWORK_TYPE_ALL) {
+            builder.append(", subType=").append(mSubType);
+        }
+        if (mOemManaged != OEM_MANAGED_ALL) {
+            builder.append(", oemManaged=").append(getOemManagedNames(mOemManaged));
+        }
+        builder.append(", subscriberIdMatchRule=")
+                .append(subscriberIdMatchRuleToString(mSubscriberIdMatchRule));
+        return builder.toString();
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mMatchRule, mSubscriberId, mNetworkId, mMetered, mRoaming,
+                mDefaultNetwork, mSubType, mOemManaged, mSubscriberIdMatchRule);
+    }
+
+    @Override
+    public boolean equals(@Nullable Object obj) {
+        if (obj instanceof NetworkTemplate) {
+            final NetworkTemplate other = (NetworkTemplate) obj;
+            return mMatchRule == other.mMatchRule
+                    && Objects.equals(mSubscriberId, other.mSubscriberId)
+                    && Objects.equals(mNetworkId, other.mNetworkId)
+                    && mMetered == other.mMetered
+                    && mRoaming == other.mRoaming
+                    && mDefaultNetwork == other.mDefaultNetwork
+                    && mSubType == other.mSubType
+                    && mOemManaged == other.mOemManaged
+                    && mSubscriberIdMatchRule == other.mSubscriberIdMatchRule;
+        }
+        return false;
+    }
+
+    private String subscriberIdMatchRuleToString(int rule) {
+        switch (rule) {
+            case SUBSCRIBER_ID_MATCH_RULE_EXACT:
+                return "EXACT_MATCH";
+            case SUBSCRIBER_ID_MATCH_RULE_ALL:
+                return "ALL";
+            default:
+                return "Unknown rule " + rule;
+        }
+    }
+
+    public boolean isMatchRuleMobile() {
+        switch (mMatchRule) {
+            case MATCH_MOBILE:
+            case MATCH_MOBILE_WILDCARD:
+                return true;
+            default:
+                return false;
+        }
+    }
+
+    public boolean isPersistable() {
+        switch (mMatchRule) {
+            case MATCH_MOBILE_WILDCARD:
+            case MATCH_WIFI_WILDCARD:
+                return false;
+            case MATCH_CARRIER:
+                return mSubscriberId != null;
+            case MATCH_WIFI:
+                if (Objects.equals(mNetworkId, WIFI_NETWORKID_ALL)
+                        && mSubscriberIdMatchRule == SUBSCRIBER_ID_MATCH_RULE_ALL) {
+                    return false;
+                }
+                return true;
+            default:
+                return true;
+        }
+    }
+
+    @UnsupportedAppUsage
+    public int getMatchRule() {
+        return mMatchRule;
+    }
+
+    @UnsupportedAppUsage
+    public String getSubscriberId() {
+        return mSubscriberId;
+    }
+
+    public String getNetworkId() {
+        return mNetworkId;
+    }
+
+    public int getSubscriberIdMatchRule() {
+        return mSubscriberIdMatchRule;
+    }
+
+    public int getMeteredness() {
+        return mMetered;
+    }
+
+    /**
+     * Test if given {@link NetworkIdentity} matches this template.
+     */
+    public boolean matches(NetworkIdentity ident) {
+        if (!matchesMetered(ident)) return false;
+        if (!matchesRoaming(ident)) return false;
+        if (!matchesDefaultNetwork(ident)) return false;
+        if (!matchesOemNetwork(ident)) return false;
+
+        switch (mMatchRule) {
+            case MATCH_MOBILE:
+                return matchesMobile(ident);
+            case MATCH_WIFI:
+                return matchesWifi(ident);
+            case MATCH_ETHERNET:
+                return matchesEthernet(ident);
+            case MATCH_MOBILE_WILDCARD:
+                return matchesMobileWildcard(ident);
+            case MATCH_WIFI_WILDCARD:
+                return matchesWifiWildcard(ident);
+            case MATCH_BLUETOOTH:
+                return matchesBluetooth(ident);
+            case MATCH_PROXY:
+                return matchesProxy(ident);
+            case MATCH_CARRIER:
+                return matchesCarrier(ident);
+            default:
+                // We have no idea what kind of network template we are, so we
+                // just claim not to match anything.
+                return false;
+        }
+    }
+
+    private boolean matchesMetered(NetworkIdentity ident) {
+        return (mMetered == METERED_ALL)
+            || (mMetered == METERED_YES && ident.mMetered)
+            || (mMetered == METERED_NO && !ident.mMetered);
+    }
+
+    private boolean matchesRoaming(NetworkIdentity ident) {
+        return (mRoaming == ROAMING_ALL)
+            || (mRoaming == ROAMING_YES && ident.mRoaming)
+            || (mRoaming == ROAMING_NO && !ident.mRoaming);
+    }
+
+    private boolean matchesDefaultNetwork(NetworkIdentity ident) {
+        return (mDefaultNetwork == DEFAULT_NETWORK_ALL)
+            || (mDefaultNetwork == DEFAULT_NETWORK_YES && ident.mDefaultNetwork)
+            || (mDefaultNetwork == DEFAULT_NETWORK_NO && !ident.mDefaultNetwork);
+    }
+
+    private boolean matchesOemNetwork(NetworkIdentity ident) {
+        return (mOemManaged == OEM_MANAGED_ALL)
+            || (mOemManaged == OEM_MANAGED_YES
+                    && ident.mOemManaged != OEM_NONE)
+            || (mOemManaged == ident.mOemManaged);
+    }
+
+    private boolean matchesCollapsedRatType(NetworkIdentity ident) {
+        return mSubType == NETWORK_TYPE_ALL
+                || getCollapsedRatType(mSubType) == getCollapsedRatType(ident.mSubType);
+    }
+
+    /**
+     * Check if this template matches {@code subscriberId}. Returns true if this
+     * template was created with {@code SUBSCRIBER_ID_MATCH_RULE_ALL}, or with a
+     * {@code mMatchSubscriberIds} array that contains {@code subscriberId}.
+     */
+    public boolean matchesSubscriberId(@Nullable String subscriberId) {
+        return mSubscriberIdMatchRule == SUBSCRIBER_ID_MATCH_RULE_ALL
+                || ArrayUtils.contains(mMatchSubscriberIds, subscriberId);
+    }
+
+    /**
+     * Check if network with matching SSID. Returns true when the SSID matches, or when
+     * {@code mNetworkId} is {@code WIFI_NETWORKID_ALL}.
+     */
+    private boolean matchesWifiNetworkId(@Nullable String networkId) {
+        return Objects.equals(mNetworkId, WIFI_NETWORKID_ALL)
+                || Objects.equals(sanitizeSsid(mNetworkId), sanitizeSsid(networkId));
+    }
+
+    /**
+     * Check if mobile network with matching IMSI.
+     */
+    private boolean matchesMobile(NetworkIdentity ident) {
+        if (ident.mType == TYPE_WIMAX) {
+            // TODO: consider matching against WiMAX subscriber identity
+            return true;
+        } else {
+            return ident.mType == TYPE_MOBILE && !ArrayUtils.isEmpty(mMatchSubscriberIds)
+                    && ArrayUtils.contains(mMatchSubscriberIds, ident.mSubscriberId)
+                    && matchesCollapsedRatType(ident);
+        }
+    }
+
+    /**
+     * Get a Radio Access Technology(RAT) type that is representative of a group of RAT types.
+     * The mapping is corresponding to {@code TelephonyManager#NETWORK_CLASS_BIT_MASK_*}.
+     *
+     * @param ratType An integer defined in {@code TelephonyManager#NETWORK_TYPE_*}.
+     */
+    // TODO: 1. Consider move this to TelephonyManager if used by other modules.
+    //       2. Consider make this configurable.
+    //       3. Use TelephonyManager APIs when available.
+    public static int getCollapsedRatType(int ratType) {
+        switch (ratType) {
+            case TelephonyManager.NETWORK_TYPE_GPRS:
+            case TelephonyManager.NETWORK_TYPE_GSM:
+            case TelephonyManager.NETWORK_TYPE_EDGE:
+            case TelephonyManager.NETWORK_TYPE_IDEN:
+            case TelephonyManager.NETWORK_TYPE_CDMA:
+            case TelephonyManager.NETWORK_TYPE_1xRTT:
+                return TelephonyManager.NETWORK_TYPE_GSM;
+            case TelephonyManager.NETWORK_TYPE_EVDO_0:
+            case TelephonyManager.NETWORK_TYPE_EVDO_A:
+            case TelephonyManager.NETWORK_TYPE_EVDO_B:
+            case TelephonyManager.NETWORK_TYPE_EHRPD:
+            case TelephonyManager.NETWORK_TYPE_UMTS:
+            case TelephonyManager.NETWORK_TYPE_HSDPA:
+            case TelephonyManager.NETWORK_TYPE_HSUPA:
+            case TelephonyManager.NETWORK_TYPE_HSPA:
+            case TelephonyManager.NETWORK_TYPE_HSPAP:
+            case TelephonyManager.NETWORK_TYPE_TD_SCDMA:
+                return TelephonyManager.NETWORK_TYPE_UMTS;
+            case TelephonyManager.NETWORK_TYPE_LTE:
+            case TelephonyManager.NETWORK_TYPE_IWLAN:
+                return TelephonyManager.NETWORK_TYPE_LTE;
+            case TelephonyManager.NETWORK_TYPE_NR:
+                return TelephonyManager.NETWORK_TYPE_NR;
+            // Virtual RAT type for 5G NSA mode, see {@link NetworkTemplate#NETWORK_TYPE_5G_NSA}.
+            case NetworkTemplate.NETWORK_TYPE_5G_NSA:
+                return NetworkTemplate.NETWORK_TYPE_5G_NSA;
+            default:
+                return TelephonyManager.NETWORK_TYPE_UNKNOWN;
+        }
+    }
+
+    /**
+     * Return all supported collapsed RAT types that could be returned by
+     * {@link #getCollapsedRatType(int)}.
+     */
+    @NonNull
+    public static final int[] getAllCollapsedRatTypes() {
+        final int[] ratTypes = TelephonyManager.getAllNetworkTypes();
+        final HashSet<Integer> collapsedRatTypes = new HashSet<>();
+        for (final int ratType : ratTypes) {
+            collapsedRatTypes.add(NetworkTemplate.getCollapsedRatType(ratType));
+        }
+        // Add NETWORK_TYPE_5G_NSA to the returned list since 5G NSA is a virtual RAT type and
+        // it is not in TelephonyManager#NETWORK_TYPE_* constants.
+        // See {@link NetworkTemplate#NETWORK_TYPE_5G_NSA}.
+        collapsedRatTypes.add(NetworkTemplate.getCollapsedRatType(NETWORK_TYPE_5G_NSA));
+        // Ensure that unknown type is returned.
+        collapsedRatTypes.add(TelephonyManager.NETWORK_TYPE_UNKNOWN);
+        return toIntArray(collapsedRatTypes);
+    }
+
+    @NonNull
+    private static int[] toIntArray(@NonNull Collection<Integer> list) {
+        final int[] array = new int[list.size()];
+        int i = 0;
+        for (final Integer item : list) {
+            array[i++] = item;
+        }
+        return array;
+    }
+
+    /**
+     * Check if matches Wi-Fi network template.
+     */
+    private boolean matchesWifi(NetworkIdentity ident) {
+        switch (ident.mType) {
+            case TYPE_WIFI:
+                return matchesSubscriberId(ident.mSubscriberId)
+                        && matchesWifiNetworkId(ident.mNetworkId);
+            default:
+                return false;
+        }
+    }
+
+    /**
+     * Check if matches Ethernet network template.
+     */
+    private boolean matchesEthernet(NetworkIdentity ident) {
+        if (ident.mType == TYPE_ETHERNET) {
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Check if matches carrier network. The carrier networks means it includes the subscriberId.
+     */
+    private boolean matchesCarrier(NetworkIdentity ident) {
+        return ident.mSubscriberId != null
+                && !ArrayUtils.isEmpty(mMatchSubscriberIds)
+                && ArrayUtils.contains(mMatchSubscriberIds, ident.mSubscriberId);
+    }
+
+    private boolean matchesMobileWildcard(NetworkIdentity ident) {
+        if (ident.mType == TYPE_WIMAX) {
+            return true;
+        } else {
+            return ident.mType == TYPE_MOBILE && matchesCollapsedRatType(ident);
+        }
+    }
+
+    private boolean matchesWifiWildcard(NetworkIdentity ident) {
+        switch (ident.mType) {
+            case TYPE_WIFI:
+            case TYPE_WIFI_P2P:
+                return true;
+            default:
+                return false;
+        }
+    }
+
+    /**
+     * Check if matches Bluetooth network template.
+     */
+    private boolean matchesBluetooth(NetworkIdentity ident) {
+        if (ident.mType == TYPE_BLUETOOTH) {
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Check if matches Proxy network template.
+     */
+    private boolean matchesProxy(NetworkIdentity ident) {
+        return ident.mType == TYPE_PROXY;
+    }
+
+    private static String getMatchRuleName(int matchRule) {
+        switch (matchRule) {
+            case MATCH_MOBILE:
+                return "MOBILE";
+            case MATCH_WIFI:
+                return "WIFI";
+            case MATCH_ETHERNET:
+                return "ETHERNET";
+            case MATCH_MOBILE_WILDCARD:
+                return "MOBILE_WILDCARD";
+            case MATCH_WIFI_WILDCARD:
+                return "WIFI_WILDCARD";
+            case MATCH_BLUETOOTH:
+                return "BLUETOOTH";
+            case MATCH_PROXY:
+                return "PROXY";
+            case MATCH_CARRIER:
+                return "CARRIER";
+            default:
+                return "UNKNOWN(" + matchRule + ")";
+        }
+    }
+
+    private static String getOemManagedNames(int oemManaged) {
+        switch (oemManaged) {
+            case OEM_MANAGED_ALL:
+                return "OEM_MANAGED_ALL";
+            case OEM_MANAGED_NO:
+                return "OEM_MANAGED_NO";
+            case OEM_MANAGED_YES:
+                return "OEM_MANAGED_YES";
+            default:
+                return NetworkIdentity.getOemManagedNames(oemManaged);
+        }
+    }
+
+    /**
+     * Examine the given template and normalize it.
+     * We pick the "lowest" merged subscriber as the primary
+     * for key purposes, and expand the template to match all other merged
+     * subscribers.
+     * <p>
+     * For example, given an incoming template matching B, and the currently
+     * active merge set [A,B], we'd return a new template that primarily matches
+     * A, but also matches B.
+     * TODO: remove and use {@link #normalize(NetworkTemplate, List)}.
+     */
+    @UnsupportedAppUsage
+    public static NetworkTemplate normalize(NetworkTemplate template, String[] merged) {
+        return normalize(template, Arrays.<String[]>asList(merged));
+    }
+
+    /**
+     * Examine the given template and normalize it.
+     * We pick the "lowest" merged subscriber as the primary
+     * for key purposes, and expand the template to match all other merged
+     * subscribers.
+     *
+     * There can be multiple merged subscriberIds for multi-SIM devices.
+     *
+     * <p>
+     * For example, given an incoming template matching B, and the currently
+     * active merge set [A,B], we'd return a new template that primarily matches
+     * A, but also matches B.
+     */
+    public static NetworkTemplate normalize(NetworkTemplate template, List<String[]> mergedList) {
+        // Now there are several types of network which uses SubscriberId to store network
+        // information. For instances:
+        // The TYPE_WIFI with subscriberId means that it is a merged carrier wifi network.
+        // The TYPE_CARRIER means that the network associate to specific carrier network.
+
+        if (template.mSubscriberId == null) return template;
+
+        for (String[] merged : mergedList) {
+            if (ArrayUtils.contains(merged, template.mSubscriberId)) {
+                // Requested template subscriber is part of the merge group; return
+                // a template that matches all merged subscribers.
+                return new NetworkTemplate(template.mMatchRule, merged[0], merged,
+                        template.mNetworkId);
+            }
+        }
+
+        return template;
+    }
+
+    @UnsupportedAppUsage
+    public static final @android.annotation.NonNull Creator<NetworkTemplate> CREATOR = new Creator<NetworkTemplate>() {
+        @Override
+        public NetworkTemplate createFromParcel(Parcel in) {
+            return new NetworkTemplate(in);
+        }
+
+        @Override
+        public NetworkTemplate[] newArray(int size) {
+            return new NetworkTemplate[size];
+        }
+    };
+
+    public byte[] getBytesForBackup() throws IOException {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        DataOutputStream out = new DataOutputStream(baos);
+
+        if (!isPersistable()) {
+            Log.wtf(TAG, "Trying to backup non-persistable template: " + this);
+        }
+
+        out.writeInt(BACKUP_VERSION);
+
+        out.writeInt(mMatchRule);
+        BackupUtils.writeString(out, mSubscriberId);
+        BackupUtils.writeString(out, mNetworkId);
+        out.writeInt(mMetered);
+        out.writeInt(mSubscriberIdMatchRule);
+
+        return baos.toByteArray();
+    }
+
+    public static NetworkTemplate getNetworkTemplateFromBackup(DataInputStream in)
+            throws IOException, BackupUtils.BadVersionException {
+        int version = in.readInt();
+        if (version < BACKUP_VERSION_1_INIT || version > BACKUP_VERSION) {
+            throw new BackupUtils.BadVersionException("Unknown Backup Serialization Version");
+        }
+
+        int matchRule = in.readInt();
+        String subscriberId = BackupUtils.readString(in);
+        String networkId = BackupUtils.readString(in);
+
+        final int metered;
+        final int subscriberIdMatchRule;
+        if (version >= BACKUP_VERSION_2_SUPPORT_CARRIER_TEMPLATE) {
+            metered = in.readInt();
+            subscriberIdMatchRule = in.readInt();
+        } else {
+            // For backward compatibility, fill the missing filters from match rules.
+            metered = (matchRule == MATCH_MOBILE || matchRule == MATCH_MOBILE_WILDCARD
+                    || matchRule == MATCH_CARRIER) ? METERED_YES : METERED_ALL;
+            subscriberIdMatchRule = SUBSCRIBER_ID_MATCH_RULE_EXACT;
+        }
+
+        try {
+            return new NetworkTemplate(matchRule,
+                    subscriberId, new String[] { subscriberId },
+                    networkId, metered, NetworkStats.ROAMING_ALL,
+                    NetworkStats.DEFAULT_NETWORK_ALL, NetworkTemplate.NETWORK_TYPE_ALL,
+                    NetworkTemplate.OEM_MANAGED_ALL, subscriberIdMatchRule);
+        } catch (IllegalArgumentException e) {
+            throw new BackupUtils.BadVersionException(
+                    "Restored network template contains unknown match rule " + matchRule, e);
+        }
+    }
+}
diff --git a/framework-t/src/android/net/TrafficStats.java b/framework-t/src/android/net/TrafficStats.java
new file mode 100644
index 0000000..fa65061
--- /dev/null
+++ b/framework-t/src/android/net/TrafficStats.java
@@ -0,0 +1,1032 @@
+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import android.annotation.NonNull;
+import android.annotation.SuppressLint;
+import android.annotation.SystemApi;
+import android.annotation.TestApi;
+import android.app.DownloadManager;
+import android.app.backup.BackupManager;
+import android.app.usage.NetworkStatsManager;
+import android.compat.annotation.UnsupportedAppUsage;
+import android.content.Context;
+import android.media.MediaPlayer;
+import android.os.Build;
+import android.os.RemoteException;
+import android.os.ServiceManager;
+import android.util.DataUnit;
+
+import com.android.server.NetworkManagementSocketTagger;
+
+import dalvik.system.SocketTagger;
+
+import java.io.FileDescriptor;
+import java.io.IOException;
+import java.net.DatagramSocket;
+import java.net.Socket;
+import java.net.SocketException;
+
+/**
+ * Class that provides network traffic statistics. These statistics include
+ * bytes transmitted and received and network packets transmitted and received,
+ * over all interfaces, over the mobile interface, and on a per-UID basis.
+ * <p>
+ * These statistics may not be available on all platforms. If the statistics are
+ * not supported by this device, {@link #UNSUPPORTED} will be returned.
+ * <p>
+ * Note that the statistics returned by this class reset and start from zero
+ * after every reboot. To access more robust historical network statistics data,
+ * use {@link NetworkStatsManager} instead.
+ */
+public class TrafficStats {
+    /**
+     * The return value to indicate that the device does not support the statistic.
+     */
+    public final static int UNSUPPORTED = -1;
+
+    /** @hide @deprecated use {@link DataUnit} instead to clarify SI-vs-IEC */
+    @Deprecated
+    public static final long KB_IN_BYTES = 1024;
+    /** @hide @deprecated use {@link DataUnit} instead to clarify SI-vs-IEC */
+    @Deprecated
+    public static final long MB_IN_BYTES = KB_IN_BYTES * 1024;
+    /** @hide @deprecated use {@link DataUnit} instead to clarify SI-vs-IEC */
+    @Deprecated
+    public static final long GB_IN_BYTES = MB_IN_BYTES * 1024;
+    /** @hide @deprecated use {@link DataUnit} instead to clarify SI-vs-IEC */
+    @Deprecated
+    public static final long TB_IN_BYTES = GB_IN_BYTES * 1024;
+    /** @hide @deprecated use {@link DataUnit} instead to clarify SI-vs-IEC */
+    @Deprecated
+    public static final long PB_IN_BYTES = TB_IN_BYTES * 1024;
+
+    /**
+     * Special UID value used when collecting {@link NetworkStatsHistory} for
+     * removed applications.
+     *
+     * @hide
+     */
+    public static final int UID_REMOVED = -4;
+
+    /**
+     * Special UID value used when collecting {@link NetworkStatsHistory} for
+     * tethering traffic.
+     *
+     * @hide
+     */
+    public static final int UID_TETHERING = NetworkStats.UID_TETHERING;
+
+    /**
+     * Tag values in this range are reserved for the network stack. The network stack is
+     * running as UID {@link android.os.Process.NETWORK_STACK_UID} when in the mainline
+     * module separate process, and as the system UID otherwise.
+     */
+    /** @hide */
+    @SystemApi
+    public static final int TAG_NETWORK_STACK_RANGE_START = 0xFFFFFD00;
+    /** @hide */
+    @SystemApi
+    public static final int TAG_NETWORK_STACK_RANGE_END = 0xFFFFFEFF;
+
+    /**
+     * Tags between 0xFFFFFF00 and 0xFFFFFFFF are reserved and used internally by system services
+     * like DownloadManager when performing traffic on behalf of an application.
+     */
+    // Please note there is no enforcement of these constants, so do not rely on them to
+    // determine that the caller is a system caller.
+    /** @hide */
+    @SystemApi
+    public static final int TAG_SYSTEM_IMPERSONATION_RANGE_START = 0xFFFFFF00;
+    /** @hide */
+    @SystemApi
+    public static final int TAG_SYSTEM_IMPERSONATION_RANGE_END = 0xFFFFFF0F;
+
+    /**
+     * Tag values between these ranges are reserved for the network stack to do traffic
+     * on behalf of applications. It is a subrange of the range above.
+     */
+    /** @hide */
+    @SystemApi
+    public static final int TAG_NETWORK_STACK_IMPERSONATION_RANGE_START = 0xFFFFFF80;
+    /** @hide */
+    @SystemApi
+    public static final int TAG_NETWORK_STACK_IMPERSONATION_RANGE_END = 0xFFFFFF8F;
+
+    /**
+     * Default tag value for {@link DownloadManager} traffic.
+     *
+     * @hide
+     */
+    public static final int TAG_SYSTEM_DOWNLOAD = 0xFFFFFF01;
+
+    /**
+     * Default tag value for {@link MediaPlayer} traffic.
+     *
+     * @hide
+     */
+    public static final int TAG_SYSTEM_MEDIA = 0xFFFFFF02;
+
+    /**
+     * Default tag value for {@link BackupManager} backup traffic; that is,
+     * traffic from the device to the storage backend.
+     *
+     * @hide
+     */
+    public static final int TAG_SYSTEM_BACKUP = 0xFFFFFF03;
+
+    /**
+     * Default tag value for {@link BackupManager} restore traffic; that is,
+     * app data retrieved from the storage backend at install time.
+     *
+     * @hide
+     */
+    public static final int TAG_SYSTEM_RESTORE = 0xFFFFFF04;
+
+    /**
+     * Default tag value for code (typically APKs) downloaded by an app store on
+     * behalf of the app, such as updates.
+     *
+     * @hide
+     */
+    public static final int TAG_SYSTEM_APP = 0xFFFFFF05;
+
+    // TODO : remove this constant when Wifi code is updated
+    /** @hide */
+    public static final int TAG_SYSTEM_PROBE = 0xFFFFFF42;
+
+    private static INetworkStatsService sStatsService;
+
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 130143562)
+    private synchronized static INetworkStatsService getStatsService() {
+        if (sStatsService == null) {
+            sStatsService = INetworkStatsService.Stub.asInterface(
+                    ServiceManager.getService(Context.NETWORK_STATS_SERVICE));
+        }
+        return sStatsService;
+    }
+
+    /**
+     * Snapshot of {@link NetworkStats} when the currently active profiling
+     * session started, or {@code null} if no session active.
+     *
+     * @see #startDataProfiling(Context)
+     * @see #stopDataProfiling(Context)
+     */
+    private static NetworkStats sActiveProfilingStart;
+
+    private static Object sProfilingLock = new Object();
+
+    private static final String LOOPBACK_IFACE = "lo";
+
+    /**
+     * Set active tag to use when accounting {@link Socket} traffic originating
+     * from the current thread. Only one active tag per thread is supported.
+     * <p>
+     * Changes only take effect during subsequent calls to
+     * {@link #tagSocket(Socket)}.
+     * <p>
+     * Tags between {@code 0xFFFFFF00} and {@code 0xFFFFFFFF} are reserved and
+     * used internally by system services like {@link DownloadManager} when
+     * performing traffic on behalf of an application.
+     *
+     * @see #clearThreadStatsTag()
+     */
+    public static void setThreadStatsTag(int tag) {
+        NetworkManagementSocketTagger.setThreadSocketStatsTag(tag);
+    }
+
+    /**
+     * Set active tag to use when accounting {@link Socket} traffic originating
+     * from the current thread. Only one active tag per thread is supported.
+     * <p>
+     * Changes only take effect during subsequent calls to
+     * {@link #tagSocket(Socket)}.
+     * <p>
+     * Tags between {@code 0xFFFFFF00} and {@code 0xFFFFFFFF} are reserved and
+     * used internally by system services like {@link DownloadManager} when
+     * performing traffic on behalf of an application.
+     *
+     * @return the current tag for the calling thread, which can be used to
+     *         restore any existing values after a nested operation is finished
+     */
+    public static int getAndSetThreadStatsTag(int tag) {
+        return NetworkManagementSocketTagger.setThreadSocketStatsTag(tag);
+    }
+
+    /**
+     * Set active tag to use when accounting {@link Socket} traffic originating
+     * from the current thread. The tag used internally is well-defined to
+     * distinguish all backup-related traffic.
+     *
+     * @hide
+     */
+    @SystemApi
+    public static void setThreadStatsTagBackup() {
+        setThreadStatsTag(TAG_SYSTEM_BACKUP);
+    }
+
+    /**
+     * Set active tag to use when accounting {@link Socket} traffic originating
+     * from the current thread. The tag used internally is well-defined to
+     * distinguish all restore-related traffic.
+     *
+     * @hide
+     */
+    @SystemApi
+    public static void setThreadStatsTagRestore() {
+        setThreadStatsTag(TAG_SYSTEM_RESTORE);
+    }
+
+    /**
+     * Set active tag to use when accounting {@link Socket} traffic originating
+     * from the current thread. The tag used internally is well-defined to
+     * distinguish all code (typically APKs) downloaded by an app store on
+     * behalf of the app, such as updates.
+     *
+     * @hide
+     */
+    @SystemApi
+    public static void setThreadStatsTagApp() {
+        setThreadStatsTag(TAG_SYSTEM_APP);
+    }
+
+    /**
+     * Get the active tag used when accounting {@link Socket} traffic originating
+     * from the current thread. Only one active tag per thread is supported.
+     * {@link #tagSocket(Socket)}.
+     *
+     * @see #setThreadStatsTag(int)
+     */
+    public static int getThreadStatsTag() {
+        return NetworkManagementSocketTagger.getThreadSocketStatsTag();
+    }
+
+    /**
+     * Clear any active tag set to account {@link Socket} traffic originating
+     * from the current thread.
+     *
+     * @see #setThreadStatsTag(int)
+     */
+    public static void clearThreadStatsTag() {
+        NetworkManagementSocketTagger.setThreadSocketStatsTag(-1);
+    }
+
+    /**
+     * Set specific UID to use when accounting {@link Socket} traffic
+     * originating from the current thread. Designed for use when performing an
+     * operation on behalf of another application, or when another application
+     * is performing operations on your behalf.
+     * <p>
+     * Any app can <em>accept</em> blame for traffic performed on a socket
+     * originally created by another app by calling this method with the
+     * {@link android.system.Os#getuid()} value. However, only apps holding the
+     * {@code android.Manifest.permission#UPDATE_DEVICE_STATS} permission may
+     * <em>assign</em> blame to another UIDs.
+     * <p>
+     * Changes only take effect during subsequent calls to
+     * {@link #tagSocket(Socket)}.
+     */
+    @SuppressLint("RequiresPermission")
+    public static void setThreadStatsUid(int uid) {
+        NetworkManagementSocketTagger.setThreadSocketStatsUid(uid);
+    }
+
+    /**
+     * Get the active UID used when accounting {@link Socket} traffic originating
+     * from the current thread. Only one active tag per thread is supported.
+     * {@link #tagSocket(Socket)}.
+     *
+     * @see #setThreadStatsUid(int)
+     */
+    public static int getThreadStatsUid() {
+        return NetworkManagementSocketTagger.getThreadSocketStatsUid();
+    }
+
+    /**
+     * Set specific UID to use when accounting {@link Socket} traffic
+     * originating from the current thread as the calling UID. Designed for use
+     * when another application is performing operations on your behalf.
+     * <p>
+     * Changes only take effect during subsequent calls to
+     * {@link #tagSocket(Socket)}.
+     *
+     * @removed
+     * @deprecated use {@link #setThreadStatsUid(int)} instead.
+     */
+    @Deprecated
+    public static void setThreadStatsUidSelf() {
+        setThreadStatsUid(android.os.Process.myUid());
+    }
+
+    /**
+     * Clear any active UID set to account {@link Socket} traffic originating
+     * from the current thread.
+     *
+     * @see #setThreadStatsUid(int)
+     */
+    @SuppressLint("RequiresPermission")
+    public static void clearThreadStatsUid() {
+        NetworkManagementSocketTagger.setThreadSocketStatsUid(-1);
+    }
+
+    /**
+     * Tag the given {@link Socket} with any statistics parameters active for
+     * the current thread. Subsequent calls always replace any existing
+     * parameters. When finished, call {@link #untagSocket(Socket)} to remove
+     * statistics parameters.
+     *
+     * @see #setThreadStatsTag(int)
+     */
+    public static void tagSocket(Socket socket) throws SocketException {
+        SocketTagger.get().tag(socket);
+    }
+
+    /**
+     * Remove any statistics parameters from the given {@link Socket}.
+     * <p>
+     * In Android 8.1 (API level 27) and lower, a socket is automatically
+     * untagged when it's sent to another process using binder IPC with a
+     * {@code ParcelFileDescriptor} container. In Android 9.0 (API level 28)
+     * and higher, the socket tag is kept when the socket is sent to another
+     * process using binder IPC. You can mimic the previous behavior by
+     * calling {@code untagSocket()} before sending the socket to another
+     * process.
+     */
+    public static void untagSocket(Socket socket) throws SocketException {
+        SocketTagger.get().untag(socket);
+    }
+
+    /**
+     * Tag the given {@link DatagramSocket} with any statistics parameters
+     * active for the current thread. Subsequent calls always replace any
+     * existing parameters. When finished, call
+     * {@link #untagDatagramSocket(DatagramSocket)} to remove statistics
+     * parameters.
+     *
+     * @see #setThreadStatsTag(int)
+     */
+    public static void tagDatagramSocket(DatagramSocket socket) throws SocketException {
+        SocketTagger.get().tag(socket);
+    }
+
+    /**
+     * Remove any statistics parameters from the given {@link DatagramSocket}.
+     */
+    public static void untagDatagramSocket(DatagramSocket socket) throws SocketException {
+        SocketTagger.get().untag(socket);
+    }
+
+    /**
+     * Tag the given {@link FileDescriptor} socket with any statistics
+     * parameters active for the current thread. Subsequent calls always replace
+     * any existing parameters. When finished, call
+     * {@link #untagFileDescriptor(FileDescriptor)} to remove statistics
+     * parameters.
+     *
+     * @see #setThreadStatsTag(int)
+     */
+    public static void tagFileDescriptor(FileDescriptor fd) throws IOException {
+        SocketTagger.get().tag(fd);
+    }
+
+    /**
+     * Remove any statistics parameters from the given {@link FileDescriptor}
+     * socket.
+     */
+    public static void untagFileDescriptor(FileDescriptor fd) throws IOException {
+        SocketTagger.get().untag(fd);
+    }
+
+    /**
+     * Start profiling data usage for current UID. Only one profiling session
+     * can be active at a time.
+     *
+     * @hide
+     */
+    public static void startDataProfiling(Context context) {
+        synchronized (sProfilingLock) {
+            if (sActiveProfilingStart != null) {
+                throw new IllegalStateException("already profiling data");
+            }
+
+            // take snapshot in time; we calculate delta later
+            sActiveProfilingStart = getDataLayerSnapshotForUid(context);
+        }
+    }
+
+    /**
+     * Stop profiling data usage for current UID.
+     *
+     * @return Detailed {@link NetworkStats} of data that occurred since last
+     *         {@link #startDataProfiling(Context)} call.
+     * @hide
+     */
+    public static NetworkStats stopDataProfiling(Context context) {
+        synchronized (sProfilingLock) {
+            if (sActiveProfilingStart == null) {
+                throw new IllegalStateException("not profiling data");
+            }
+
+            // subtract starting values and return delta
+            final NetworkStats profilingStop = getDataLayerSnapshotForUid(context);
+            final NetworkStats profilingDelta = NetworkStats.subtract(
+                    profilingStop, sActiveProfilingStart, null, null);
+            sActiveProfilingStart = null;
+            return profilingDelta;
+        }
+    }
+
+    /**
+     * Increment count of network operations performed under the accounting tag
+     * currently active on the calling thread. This can be used to derive
+     * bytes-per-operation.
+     *
+     * @param operationCount Number of operations to increment count by.
+     */
+    public static void incrementOperationCount(int operationCount) {
+        final int tag = getThreadStatsTag();
+        incrementOperationCount(tag, operationCount);
+    }
+
+    /**
+     * Increment count of network operations performed under the given
+     * accounting tag. This can be used to derive bytes-per-operation.
+     *
+     * @param tag Accounting tag used in {@link #setThreadStatsTag(int)}.
+     * @param operationCount Number of operations to increment count by.
+     */
+    public static void incrementOperationCount(int tag, int operationCount) {
+        final int uid = android.os.Process.myUid();
+        try {
+            getStatsService().incrementOperationCount(uid, tag, operationCount);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /** {@hide} */
+    public static void closeQuietly(INetworkStatsSession session) {
+        // TODO: move to NetworkStatsService once it exists
+        if (session != null) {
+            try {
+                session.close();
+            } catch (RuntimeException rethrown) {
+                throw rethrown;
+            } catch (Exception ignored) {
+            }
+        }
+    }
+
+    private static long addIfSupported(long stat) {
+        return (stat == UNSUPPORTED) ? 0 : stat;
+    }
+
+    /**
+     * Return number of packets transmitted across mobile networks since device
+     * boot. Counts packets across all mobile network interfaces, and always
+     * increases monotonically since device boot. Statistics are measured at the
+     * network layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getMobileTxPackets() {
+        long total = 0;
+        for (String iface : getMobileIfaces()) {
+            total += addIfSupported(getTxPackets(iface));
+        }
+        return total;
+    }
+
+    /**
+     * Return number of packets received across mobile networks since device
+     * boot. Counts packets across all mobile network interfaces, and always
+     * increases monotonically since device boot. Statistics are measured at the
+     * network layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getMobileRxPackets() {
+        long total = 0;
+        for (String iface : getMobileIfaces()) {
+            total += addIfSupported(getRxPackets(iface));
+        }
+        return total;
+    }
+
+    /**
+     * Return number of bytes transmitted across mobile networks since device
+     * boot. Counts packets across all mobile network interfaces, and always
+     * increases monotonically since device boot. Statistics are measured at the
+     * network layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getMobileTxBytes() {
+        long total = 0;
+        for (String iface : getMobileIfaces()) {
+            total += addIfSupported(getTxBytes(iface));
+        }
+        return total;
+    }
+
+    /**
+     * Return number of bytes received across mobile networks since device boot.
+     * Counts packets across all mobile network interfaces, and always increases
+     * monotonically since device boot. Statistics are measured at the network
+     * layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getMobileRxBytes() {
+        long total = 0;
+        for (String iface : getMobileIfaces()) {
+            total += addIfSupported(getRxBytes(iface));
+        }
+        return total;
+    }
+
+    /** {@hide} */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public static long getMobileTcpRxPackets() {
+        long total = 0;
+        for (String iface : getMobileIfaces()) {
+            long stat = UNSUPPORTED;
+            try {
+                stat = getStatsService().getIfaceStats(iface, TYPE_TCP_RX_PACKETS);
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            }
+            total += addIfSupported(stat);
+        }
+        return total;
+    }
+
+    /** {@hide} */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
+    public static long getMobileTcpTxPackets() {
+        long total = 0;
+        for (String iface : getMobileIfaces()) {
+            long stat = UNSUPPORTED;
+            try {
+                stat = getStatsService().getIfaceStats(iface, TYPE_TCP_TX_PACKETS);
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            }
+            total += addIfSupported(stat);
+        }
+        return total;
+    }
+
+    /**
+     * Return the number of packets transmitted on the specified interface since the interface
+     * was created. Statistics are measured at the network layer, so both TCP and
+     * UDP usage are included.
+     *
+     * Note that the returned values are partial statistics that do not count data from several
+     * sources and do not apply several adjustments that are necessary for correctness, such
+     * as adjusting for VPN apps, IPv6-in-IPv4 translation, etc. These values can be used to
+     * determine whether traffic is being transferred on the specific interface but are not a
+     * substitute for the more accurate statistics provided by the {@link NetworkStatsManager}
+     * APIs.
+     *
+     * @param iface The name of the interface.
+     * @return The number of transmitted packets.
+     */
+    public static long getTxPackets(@NonNull String iface) {
+        try {
+            return getStatsService().getIfaceStats(iface, TYPE_TX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return the number of packets received on the specified interface since the interface was
+     * created. Statistics are measured at the network layer, so both TCP
+     * and UDP usage are included.
+     *
+     * Note that the returned values are partial statistics that do not count data from several
+     * sources and do not apply several adjustments that are necessary for correctness, such
+     * as adjusting for VPN apps, IPv6-in-IPv4 translation, etc. These values can be used to
+     * determine whether traffic is being transferred on the specific interface but are not a
+     * substitute for the more accurate statistics provided by the {@link NetworkStatsManager}
+     * APIs.
+     *
+     * @param iface The name of the interface.
+     * @return The number of received packets.
+     */
+    public static long getRxPackets(@NonNull String iface) {
+        try {
+            return getStatsService().getIfaceStats(iface, TYPE_RX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return the number of bytes transmitted on the specified interface since the interface
+     * was created. Statistics are measured at the network layer, so both TCP and
+     * UDP usage are included.
+     *
+     * Note that the returned values are partial statistics that do not count data from several
+     * sources and do not apply several adjustments that are necessary for correctness, such
+     * as adjusting for VPN apps, IPv6-in-IPv4 translation, etc. These values can be used to
+     * determine whether traffic is being transferred on the specific interface but are not a
+     * substitute for the more accurate statistics provided by the {@link NetworkStatsManager}
+     * APIs.
+     *
+     * @param iface The name of the interface.
+     * @return The number of transmitted bytes.
+     */
+    public static long getTxBytes(@NonNull String iface) {
+        try {
+            return getStatsService().getIfaceStats(iface, TYPE_TX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return the number of bytes received on the specified interface since the interface
+     * was created. Statistics are measured at the network layer, so both TCP
+     * and UDP usage are included.
+     *
+     * Note that the returned values are partial statistics that do not count data from several
+     * sources and do not apply several adjustments that are necessary for correctness, such
+     * as adjusting for VPN apps, IPv6-in-IPv4 translation, etc. These values can be used to
+     * determine whether traffic is being transferred on the specific interface but are not a
+     * substitute for the more accurate statistics provided by the {@link NetworkStatsManager}
+     * APIs.
+     *
+     * @param iface The name of the interface.
+     * @return The number of received bytes.
+     */
+    public static long getRxBytes(@NonNull String iface) {
+        try {
+            return getStatsService().getIfaceStats(iface, TYPE_RX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /** {@hide} */
+    @TestApi
+    public static long getLoopbackTxPackets() {
+        try {
+            return getStatsService().getIfaceStats(LOOPBACK_IFACE, TYPE_TX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /** {@hide} */
+    @TestApi
+    public static long getLoopbackRxPackets() {
+        try {
+            return getStatsService().getIfaceStats(LOOPBACK_IFACE, TYPE_RX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /** {@hide} */
+    @TestApi
+    public static long getLoopbackTxBytes() {
+        try {
+            return getStatsService().getIfaceStats(LOOPBACK_IFACE, TYPE_TX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /** {@hide} */
+    @TestApi
+    public static long getLoopbackRxBytes() {
+        try {
+            return getStatsService().getIfaceStats(LOOPBACK_IFACE, TYPE_RX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of packets transmitted since device boot. Counts packets
+     * across all network interfaces, and always increases monotonically since
+     * device boot. Statistics are measured at the network layer, so they
+     * include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getTotalTxPackets() {
+        try {
+            return getStatsService().getTotalStats(TYPE_TX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of packets received since device boot. Counts packets
+     * across all network interfaces, and always increases monotonically since
+     * device boot. Statistics are measured at the network layer, so they
+     * include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getTotalRxPackets() {
+        try {
+            return getStatsService().getTotalStats(TYPE_RX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of bytes transmitted since device boot. Counts packets
+     * across all network interfaces, and always increases monotonically since
+     * device boot. Statistics are measured at the network layer, so they
+     * include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getTotalTxBytes() {
+        try {
+            return getStatsService().getTotalStats(TYPE_TX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of bytes received since device boot. Counts packets across
+     * all network interfaces, and always increases monotonically since device
+     * boot. Statistics are measured at the network layer, so they include both
+     * TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     */
+    public static long getTotalRxBytes() {
+        try {
+            return getStatsService().getTotalStats(TYPE_RX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of bytes transmitted by the given UID since device boot.
+     * Counts packets across all network interfaces, and always increases
+     * monotonically since device boot. Statistics are measured at the network
+     * layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may
+     * return {@link #UNSUPPORTED} on devices where statistics aren't available.
+     * <p>
+     * Starting in {@link android.os.Build.VERSION_CODES#N} this will only
+     * report traffic statistics for the calling UID. It will return
+     * {@link #UNSUPPORTED} for all other UIDs for privacy reasons. To access
+     * historical network statistics belonging to other UIDs, use
+     * {@link NetworkStatsManager}.
+     *
+     * @see android.os.Process#myUid()
+     * @see android.content.pm.ApplicationInfo#uid
+     */
+    public static long getUidTxBytes(int uid) {
+        try {
+            return getStatsService().getUidStats(uid, TYPE_TX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of bytes received by the given UID since device boot.
+     * Counts packets across all network interfaces, and always increases
+     * monotonically since device boot. Statistics are measured at the network
+     * layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may return
+     * {@link #UNSUPPORTED} on devices where statistics aren't available.
+     * <p>
+     * Starting in {@link android.os.Build.VERSION_CODES#N} this will only
+     * report traffic statistics for the calling UID. It will return
+     * {@link #UNSUPPORTED} for all other UIDs for privacy reasons. To access
+     * historical network statistics belonging to other UIDs, use
+     * {@link NetworkStatsManager}.
+     *
+     * @see android.os.Process#myUid()
+     * @see android.content.pm.ApplicationInfo#uid
+     */
+    public static long getUidRxBytes(int uid) {
+        try {
+            return getStatsService().getUidStats(uid, TYPE_RX_BYTES);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of packets transmitted by the given UID since device boot.
+     * Counts packets across all network interfaces, and always increases
+     * monotonically since device boot. Statistics are measured at the network
+     * layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may return
+     * {@link #UNSUPPORTED} on devices where statistics aren't available.
+     * <p>
+     * Starting in {@link android.os.Build.VERSION_CODES#N} this will only
+     * report traffic statistics for the calling UID. It will return
+     * {@link #UNSUPPORTED} for all other UIDs for privacy reasons. To access
+     * historical network statistics belonging to other UIDs, use
+     * {@link NetworkStatsManager}.
+     *
+     * @see android.os.Process#myUid()
+     * @see android.content.pm.ApplicationInfo#uid
+     */
+    public static long getUidTxPackets(int uid) {
+        try {
+            return getStatsService().getUidStats(uid, TYPE_TX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return number of packets received by the given UID since device boot.
+     * Counts packets across all network interfaces, and always increases
+     * monotonically since device boot. Statistics are measured at the network
+     * layer, so they include both TCP and UDP usage.
+     * <p>
+     * Before {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, this may return
+     * {@link #UNSUPPORTED} on devices where statistics aren't available.
+     * <p>
+     * Starting in {@link android.os.Build.VERSION_CODES#N} this will only
+     * report traffic statistics for the calling UID. It will return
+     * {@link #UNSUPPORTED} for all other UIDs for privacy reasons. To access
+     * historical network statistics belonging to other UIDs, use
+     * {@link NetworkStatsManager}.
+     *
+     * @see android.os.Process#myUid()
+     * @see android.content.pm.ApplicationInfo#uid
+     */
+    public static long getUidRxPackets(int uid) {
+        try {
+            return getStatsService().getUidStats(uid, TYPE_RX_PACKETS);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidTxBytes(int)
+     */
+    @Deprecated
+    public static long getUidTcpTxBytes(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidRxBytes(int)
+     */
+    @Deprecated
+    public static long getUidTcpRxBytes(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidTxBytes(int)
+     */
+    @Deprecated
+    public static long getUidUdpTxBytes(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidRxBytes(int)
+     */
+    @Deprecated
+    public static long getUidUdpRxBytes(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidTxPackets(int)
+     */
+    @Deprecated
+    public static long getUidTcpTxSegments(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidRxPackets(int)
+     */
+    @Deprecated
+    public static long getUidTcpRxSegments(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidTxPackets(int)
+     */
+    @Deprecated
+    public static long getUidUdpTxPackets(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * @deprecated Starting in {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2},
+     *             transport layer statistics are no longer available, and will
+     *             always return {@link #UNSUPPORTED}.
+     * @see #getUidRxPackets(int)
+     */
+    @Deprecated
+    public static long getUidUdpRxPackets(int uid) {
+        return UNSUPPORTED;
+    }
+
+    /**
+     * Return detailed {@link NetworkStats} for the current UID. Requires no
+     * special permission.
+     */
+    private static NetworkStats getDataLayerSnapshotForUid(Context context) {
+        // TODO: take snapshot locally, since proc file is now visible
+        final int uid = android.os.Process.myUid();
+        try {
+            return getStatsService().getDataLayerSnapshotForUid(uid);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Return set of any ifaces associated with mobile networks since boot.
+     * Interfaces are never removed from this list, so counters should always be
+     * monotonic.
+     */
+    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 130143562)
+    private static String[] getMobileIfaces() {
+        try {
+            return getStatsService().getMobileIfaces();
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    // NOTE: keep these in sync with {@code com_android_server_net_NetworkStatsService.cpp}.
+    /** {@hide} */
+    public static final int TYPE_RX_BYTES = 0;
+    /** {@hide} */
+    public static final int TYPE_RX_PACKETS = 1;
+    /** {@hide} */
+    public static final int TYPE_TX_BYTES = 2;
+    /** {@hide} */
+    public static final int TYPE_TX_PACKETS = 3;
+    /** {@hide} */
+    public static final int TYPE_TCP_RX_PACKETS = 4;
+    /** {@hide} */
+    public static final int TYPE_TCP_TX_PACKETS = 5;
+}
diff --git a/framework-t/src/android/net/UnderlyingNetworkInfo.aidl b/framework-t/src/android/net/UnderlyingNetworkInfo.aidl
new file mode 100644
index 0000000..a56f2f4
--- /dev/null
+++ b/framework-t/src/android/net/UnderlyingNetworkInfo.aidl
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+parcelable UnderlyingNetworkInfo;
diff --git a/framework-t/src/android/net/UnderlyingNetworkInfo.java b/framework-t/src/android/net/UnderlyingNetworkInfo.java
new file mode 100644
index 0000000..33f9375
--- /dev/null
+++ b/framework-t/src/android/net/UnderlyingNetworkInfo.java
@@ -0,0 +1,135 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
+
+import android.annotation.NonNull;
+import android.annotation.SystemApi;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * A lightweight container used to carry information on the networks that underly a given
+ * virtual network.
+ *
+ * @hide
+ */
+@SystemApi(client = MODULE_LIBRARIES)
+public final class UnderlyingNetworkInfo implements Parcelable {
+    /** The owner of this network. */
+    private final int mOwnerUid;
+
+    /** The interface name of this network. */
+    @NonNull
+    private final String mIface;
+
+    /** The names of the interfaces underlying this network. */
+    @NonNull
+    private final List<String> mUnderlyingIfaces;
+
+    public UnderlyingNetworkInfo(int ownerUid, @NonNull String iface,
+            @NonNull List<String> underlyingIfaces) {
+        Objects.requireNonNull(iface);
+        Objects.requireNonNull(underlyingIfaces);
+        mOwnerUid = ownerUid;
+        mIface = iface;
+        mUnderlyingIfaces = Collections.unmodifiableList(new ArrayList<>(underlyingIfaces));
+    }
+
+    private UnderlyingNetworkInfo(@NonNull Parcel in) {
+        mOwnerUid = in.readInt();
+        mIface = in.readString();
+        List<String> underlyingIfaces = new ArrayList<>();
+        in.readList(underlyingIfaces, null /*classLoader*/);
+        mUnderlyingIfaces = Collections.unmodifiableList(underlyingIfaces);
+    }
+
+    /** Get the owner of this network. */
+    public int getOwnerUid() {
+        return mOwnerUid;
+    }
+
+    /** Get the interface name of this network. */
+    @NonNull
+    public String getInterface() {
+        return mIface;
+    }
+
+    /** Get the names of the interfaces underlying this network. */
+    @NonNull
+    public List<String> getUnderlyingInterfaces() {
+        return mUnderlyingIfaces;
+    }
+
+    @Override
+    public String toString() {
+        return "UnderlyingNetworkInfo{"
+                + "ownerUid=" + mOwnerUid
+                + ", iface='" + mIface + '\''
+                + ", underlyingIfaces='" + mUnderlyingIfaces.toString() + '\''
+                + '}';
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        dest.writeInt(mOwnerUid);
+        dest.writeString(mIface);
+        dest.writeList(mUnderlyingIfaces);
+    }
+
+    @NonNull
+    public static final Parcelable.Creator<UnderlyingNetworkInfo> CREATOR =
+            new Parcelable.Creator<UnderlyingNetworkInfo>() {
+        @NonNull
+        @Override
+        public UnderlyingNetworkInfo createFromParcel(@NonNull Parcel in) {
+            return new UnderlyingNetworkInfo(in);
+        }
+
+        @NonNull
+        @Override
+        public UnderlyingNetworkInfo[] newArray(int size) {
+            return new UnderlyingNetworkInfo[size];
+        }
+    };
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (!(o instanceof UnderlyingNetworkInfo)) return false;
+        final UnderlyingNetworkInfo that = (UnderlyingNetworkInfo) o;
+        return mOwnerUid == that.getOwnerUid()
+                && Objects.equals(mIface, that.getInterface())
+                && Objects.equals(mUnderlyingIfaces, that.getUnderlyingInterfaces());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mOwnerUid, mIface, mUnderlyingIfaces);
+    }
+}
diff --git a/framework-t/src/android/net/netstats/provider/INetworkStatsProvider.aidl b/framework-t/src/android/net/netstats/provider/INetworkStatsProvider.aidl
new file mode 100644
index 0000000..74c3ba4
--- /dev/null
+++ b/framework-t/src/android/net/netstats/provider/INetworkStatsProvider.aidl
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.netstats.provider;
+
+/**
+ * Interface for NetworkStatsService to query network statistics and set data limits.
+ *
+ * @hide
+ */
+oneway interface INetworkStatsProvider {
+    void onRequestStatsUpdate(int token);
+    void onSetAlert(long quotaBytes);
+    void onSetWarningAndLimit(String iface, long warningBytes, long limitBytes);
+}
diff --git a/framework-t/src/android/net/netstats/provider/INetworkStatsProviderCallback.aidl b/framework-t/src/android/net/netstats/provider/INetworkStatsProviderCallback.aidl
new file mode 100644
index 0000000..7eaa01e
--- /dev/null
+++ b/framework-t/src/android/net/netstats/provider/INetworkStatsProviderCallback.aidl
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.netstats.provider;
+
+import android.net.NetworkStats;
+
+/**
+ * Interface for implementor of {@link INetworkStatsProviderCallback} to push events
+ * such as network statistics update or notify limit reached.
+ * @hide
+ */
+oneway interface INetworkStatsProviderCallback {
+    void notifyStatsUpdated(int token, in NetworkStats ifaceStats, in NetworkStats uidStats);
+    void notifyAlertReached();
+    void notifyWarningOrLimitReached();
+    void unregister();
+}
diff --git a/framework-t/src/android/net/netstats/provider/NetworkStatsProvider.java b/framework-t/src/android/net/netstats/provider/NetworkStatsProvider.java
new file mode 100644
index 0000000..23fc069
--- /dev/null
+++ b/framework-t/src/android/net/netstats/provider/NetworkStatsProvider.java
@@ -0,0 +1,232 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.netstats.provider;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+import android.net.NetworkStats;
+import android.os.RemoteException;
+
+/**
+ * A base class that allows external modules to implement a custom network statistics provider.
+ * @hide
+ */
+@SystemApi
+public abstract class NetworkStatsProvider {
+    /**
+     * A value used by {@link #onSetLimit}, {@link #onSetAlert} and {@link #onSetWarningAndLimit}
+     * indicates there is no limit.
+     */
+    public static final int QUOTA_UNLIMITED = -1;
+
+    @NonNull private final INetworkStatsProvider mProviderBinder =
+            new INetworkStatsProvider.Stub() {
+
+        @Override
+        public void onRequestStatsUpdate(int token) {
+            NetworkStatsProvider.this.onRequestStatsUpdate(token);
+        }
+
+        @Override
+        public void onSetAlert(long quotaBytes) {
+            NetworkStatsProvider.this.onSetAlert(quotaBytes);
+        }
+
+        @Override
+        public void onSetWarningAndLimit(String iface, long warningBytes, long limitBytes) {
+            NetworkStatsProvider.this.onSetWarningAndLimit(iface, warningBytes, limitBytes);
+        }
+    };
+
+    // The binder given by the service when successfully registering. Only null before registering,
+    // never null once non-null.
+    @Nullable
+    private INetworkStatsProviderCallback mProviderCbBinder;
+
+    /**
+     * Return the binder invoked by the service and redirect function calls to the overridden
+     * methods.
+     * @hide
+     */
+    @NonNull
+    public INetworkStatsProvider getProviderBinder() {
+        return mProviderBinder;
+    }
+
+    /**
+     * Store the binder that was returned by the service when successfully registering. Note that
+     * the provider cannot be re-registered. Hence this method can only be called once per provider.
+     *
+     * @hide
+     */
+    public void setProviderCallbackBinder(@NonNull INetworkStatsProviderCallback binder) {
+        if (mProviderCbBinder != null) {
+            throw new IllegalArgumentException("provider is already registered");
+        }
+        mProviderCbBinder = binder;
+    }
+
+    /**
+     * Get the binder that was returned by the service when successfully registering. Or null if the
+     * provider was never registered.
+     *
+     * @hide
+     */
+    @Nullable
+    public INetworkStatsProviderCallback getProviderCallbackBinder() {
+        return mProviderCbBinder;
+    }
+
+    /**
+     * Get the binder that was returned by the service when successfully registering. Throw an
+     * {@link IllegalStateException} if the provider is not registered.
+     *
+     * @hide
+     */
+    @NonNull
+    public INetworkStatsProviderCallback getProviderCallbackBinderOrThrow() {
+        if (mProviderCbBinder == null) {
+            throw new IllegalStateException("the provider is not registered");
+        }
+        return mProviderCbBinder;
+    }
+
+    /**
+     * Notify the system of new network statistics.
+     *
+     * Send the network statistics recorded since the last call to {@link #notifyStatsUpdated}. Must
+     * be called as soon as possible after {@link NetworkStatsProvider#onRequestStatsUpdate(int)}
+     * being called. Responding later increases the probability stats will be dropped. The
+     * provider can also call this whenever it wants to reports new stats for any reason.
+     * Note that the system will not necessarily immediately propagate the statistics to
+     * reflect the update.
+     *
+     * @param token the token under which these stats were gathered. Providers can call this method
+     *              with the current token as often as they want, until the token changes.
+     *              {@see NetworkStatsProvider#onRequestStatsUpdate()}
+     * @param ifaceStats the {@link NetworkStats} per interface to be reported.
+     *                   The provider should not include any traffic that is already counted by
+     *                   kernel interface counters.
+     * @param uidStats the same stats as above, but counts {@link NetworkStats}
+     *                 per uid.
+     */
+    public void notifyStatsUpdated(int token, @NonNull NetworkStats ifaceStats,
+            @NonNull NetworkStats uidStats) {
+        try {
+            getProviderCallbackBinderOrThrow().notifyStatsUpdated(token, ifaceStats, uidStats);
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Notify system that the quota set by {@code onSetAlert} has been reached.
+     */
+    public void notifyAlertReached() {
+        try {
+            getProviderCallbackBinderOrThrow().notifyAlertReached();
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Notify system that the warning set by {@link #onSetWarningAndLimit} has been reached.
+     */
+    public void notifyWarningReached() {
+        try {
+            // Reuse the code path to notify warning reached with limit reached
+            // since framework handles them in the same way.
+            getProviderCallbackBinderOrThrow().notifyWarningOrLimitReached();
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Notify system that the quota set by {@link #onSetLimit} or limit set by
+     * {@link #onSetWarningAndLimit} has been reached.
+     */
+    public void notifyLimitReached() {
+        try {
+            getProviderCallbackBinderOrThrow().notifyWarningOrLimitReached();
+        } catch (RemoteException e) {
+            e.rethrowAsRuntimeException();
+        }
+    }
+
+    /**
+     * Called by {@code NetworkStatsService} when it requires to know updated stats.
+     * The provider MUST respond by calling {@link #notifyStatsUpdated} as soon as possible.
+     * Responding later increases the probability stats will be dropped. Memory allowing, the
+     * system will try to take stats into account up to one minute after calling
+     * {@link #onRequestStatsUpdate}.
+     *
+     * @param token a positive number identifying the new state of the system under which
+     *              {@link NetworkStats} have to be gathered from now on. When this is called,
+     *              custom implementations of providers MUST tally and report the latest stats with
+     *              the previous token, under which stats were being gathered so far.
+     */
+    public abstract void onRequestStatsUpdate(int token);
+
+    /**
+     * Called by {@code NetworkStatsService} when setting the interface quota for the specified
+     * upstream interface. When this is called, the custom implementation should block all egress
+     * packets on the {@code iface} associated with the provider when {@code quotaBytes} bytes have
+     * been reached, and MUST respond to it by calling
+     * {@link NetworkStatsProvider#notifyLimitReached()}.
+     *
+     * @param iface the interface requiring the operation.
+     * @param quotaBytes the quota defined as the number of bytes, starting from zero and counting
+     *                   from now. A value of {@link #QUOTA_UNLIMITED} indicates there is no limit.
+     */
+    public abstract void onSetLimit(@NonNull String iface, long quotaBytes);
+
+    /**
+     * Called by {@code NetworkStatsService} when setting the interface quotas for the specified
+     * upstream interface. If a provider implements {@link #onSetWarningAndLimit}, the system
+     * will not call {@link #onSetLimit}. When this method is called, the implementation
+     * should behave as follows:
+     *   1. If {@code warningBytes} is reached on {@code iface}, block all further traffic on
+     *      {@code iface} and call {@link NetworkStatsProvider@notifyWarningReached()}.
+     *   2. If {@code limitBytes} is reached on {@code iface}, block all further traffic on
+     *   {@code iface} and call {@link NetworkStatsProvider#notifyLimitReached()}.
+     *
+     * @param iface the interface requiring the operation.
+     * @param warningBytes the warning defined as the number of bytes, starting from zero and
+     *                     counting from now. A value of {@link #QUOTA_UNLIMITED} indicates
+     *                     there is no warning.
+     * @param limitBytes the limit defined as the number of bytes, starting from zero and counting
+     *                   from now. A value of {@link #QUOTA_UNLIMITED} indicates there is no limit.
+     */
+    public void onSetWarningAndLimit(@NonNull String iface, long warningBytes, long limitBytes) {
+        // Backward compatibility for those who didn't override this function.
+        onSetLimit(iface, limitBytes);
+    }
+
+    /**
+     * Called by {@code NetworkStatsService} when setting the alert bytes. Custom implementations
+     * MUST call {@link NetworkStatsProvider#notifyAlertReached()} when {@code quotaBytes} bytes
+     * have been reached. Unlike {@link #onSetLimit(String, long)}, the custom implementation should
+     * not block all egress packets.
+     *
+     * @param quotaBytes the quota defined as the number of bytes, starting from zero and counting
+     *                   from now. A value of {@link #QUOTA_UNLIMITED} indicates there is no alert.
+     */
+    public abstract void onSetAlert(long quotaBytes);
+}