Addressing API council comments on NetworkStatsManager.

Callbacks
 - DataUsageCallback renamed to UsageCallback
 - DataUsagePolicy removed; passing in params directly to register method
 - making it an abstract class
 - passing in (networkType, subscriberId) that reached its threshold
 - renaming onLimitReached to onThresholdReached to match existing naming
 - only monitor single network,subscriberId
 - no monitoring of specific uids; using device or user wide instead

Tags
 - only owner uid can read its tags
 - exposing only TAG_NONE to match service side

BUG: 27530098

Change-Id: I2b2664da71806868a1e937d2bf4d1f234637509b
diff --git a/core/java/android/app/usage/NetworkStats.java b/core/java/android/app/usage/NetworkStats.java
index 9963eab..226aa8f 100644
--- a/core/java/android/app/usage/NetworkStats.java
+++ b/core/java/android/app/usage/NetworkStats.java
@@ -193,14 +193,9 @@
         public static final int ROAMING_YES = 0x2;
 
         /**
-         * Special TAG value matching any tag.
-         */
-        public static final int TAG_ANY = android.net.NetworkStats.TAG_ALL;
-
-        /**
          * Special TAG value for total data across all tags
          */
-        public static final int TAG_ALL = android.net.NetworkStats.TAG_NONE;
+        public static final int TAG_NONE = android.net.NetworkStats.TAG_NONE;
 
         private int mUid;
         private int mTag;
@@ -232,8 +227,7 @@
 
         private static int convertTag(int tag) {
             switch (tag) {
-                case android.net.NetworkStats.TAG_ALL: return TAG_ANY;
-                case android.net.NetworkStats.TAG_NONE: return TAG_ALL;
+                case android.net.NetworkStats.TAG_NONE: return TAG_NONE;
             }
             return tag;
         }
@@ -417,9 +411,9 @@
      * Collects summary results and sets summary enumeration mode.
      * @throws RemoteException
      */
-    void startSummaryEnumeration(boolean includeTags) throws RemoteException {
+    void startSummaryEnumeration() throws RemoteException {
         mSummary = mSession.getSummaryForAllUid(mTemplate, mStartTimeStamp, mEndTimeStamp,
-                includeTags);
+                false /* includeTags */);
         mEnumerationIndex = 0;
     }
 
diff --git a/core/java/android/app/usage/NetworkStatsManager.java b/core/java/android/app/usage/NetworkStatsManager.java
index 2e3aca4..4a28117 100644
--- a/core/java/android/app/usage/NetworkStatsManager.java
+++ b/core/java/android/app/usage/NetworkStatsManager.java
@@ -106,7 +106,7 @@
      * device. Result is a single Bucket aggregated over time, state, uid, tag 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_ALL}
+     * {@link NetworkStats.Bucket#UID_ALL}, tag {@link NetworkStats.Bucket#TAG_NONE}
      * and roaming {@link NetworkStats.Bucket#ROAMING_ALL}.
      *
      * @param networkType As defined in {@link ConnectivityManager}, e.g.
@@ -122,8 +122,11 @@
      */
     public Bucket querySummaryForDevice(int networkType, String subscriberId,
             long startTime, long endTime) throws SecurityException, RemoteException {
-        NetworkTemplate template = createTemplate(networkType, subscriberId);
-        if (template == null) {
+        NetworkTemplate template;
+        try {
+            template = createTemplate(networkType, subscriberId);
+        } catch (IllegalArgumentException e) {
+            if (DBG) Log.e(TAG, "Cannot create template", e);
             return null;
         }
 
@@ -136,21 +139,10 @@
     }
 
     /**
-     * Query network usage statistics summaries aggregated across tags.
-     *
-     * #see querySummaryForUser(int, String, long, long, boolean)
-     */
-    public Bucket querySummaryForUser(int networkType, String subscriberId, long startTime,
-            long endTime) throws SecurityException, RemoteException {
-        return querySummaryForUser(networkType, subscriberId, startTime, endTime,
-            false /* includeTags */);
-    }
-
-    /**
      * 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} and uid
+     * and 'endTime' parameters, state is going to be {@link NetworkStats.Bucket#STATE_ALL} and uid
      * {@link NetworkStats.Bucket#UID_ALL}.
      *
      * @param networkType As defined in {@link ConnectivityManager}, e.g.
@@ -161,42 +153,33 @@
      *            {@link java.lang.System#currentTimeMillis}.
      * @param endTime End of period. Defined in terms of "Unix time", see
      *            {@link java.lang.System#currentTimeMillis}.
-     * @param includeTags whether to include network tags. If {@code true}, tags will be returned
-     *            and history retention may be shorter.
      * @return Bucket object or null if permissions are insufficient or error happened during
      *         statistics collection.
      */
     public Bucket querySummaryForUser(int networkType, String subscriberId, long startTime,
-            long endTime, boolean includeTags) throws SecurityException, RemoteException {
-        NetworkTemplate template = createTemplate(networkType, subscriberId);
-        if (template == null) {
+            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, startTime, endTime);
-        stats.startSummaryEnumeration(includeTags);
+        stats.startSummaryEnumeration();
 
         stats.close();
         return stats.getSummaryAggregate();
     }
 
     /**
-     * Query network usage statistics summaries aggregated across tags.
-     *
-     * #see querySummary(int, String, long, long, boolean)
-     */
-    public NetworkStats querySummary(int networkType, String subscriberId, long startTime,
-            long endTime) throws SecurityException, RemoteException {
-        return querySummary(networkType, subscriberId, startTime, endTime, false /* includeTags */);
-    }
-
-    /**
      * 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 or uid or tag. This means buckets' start and end
-     * timestamps are going to be the same as the 'startTime' and 'endTime' parameters. State,
-     * uid and tag are going to vary.
+     * end timestamps. Not aggregated over state or uid. This means buckets' start and end
+     * timestamps are going to be the same as the 'startTime' and 'endTime' parameters.
+     * State and uid are going to vary, and tag is going to be the same.
      *
      * @param networkType As defined in {@link ConnectivityManager}, e.g.
      *            {@link ConnectivityManager#TYPE_MOBILE}, {@link ConnectivityManager#TYPE_WIFI}
@@ -206,21 +189,22 @@
      *            {@link java.lang.System#currentTimeMillis}.
      * @param endTime End of period. Defined in terms of "Unix time", see
      *            {@link java.lang.System#currentTimeMillis}.
-     * @param includeTags whether to include network tags. If {@code true}, tags will be returned
-     *            and history retention may be shorter.
      * @return Statistics object or null if permissions are insufficient or error happened during
      *         statistics collection.
      */
     public NetworkStats querySummary(int networkType, String subscriberId, long startTime,
-            long endTime, boolean includeTags) throws SecurityException, RemoteException {
-        NetworkTemplate template = createTemplate(networkType, subscriberId);
-        if (template == null) {
+            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, startTime, endTime);
-        result.startSummaryEnumeration(includeTags);
+        result.startSummaryEnumeration();
 
         return result;
     }
@@ -233,7 +217,7 @@
     public NetworkStats queryDetailsForUid(int networkType, String subscriberId,
             long startTime, long endTime, int uid) throws SecurityException, RemoteException {
         return queryDetailsForUidTag(networkType, subscriberId, startTime, endTime, uid,
-            NetworkStats.Bucket.TAG_ALL);
+            NetworkStats.Bucket.TAG_NONE);
     }
 
     /**
@@ -255,22 +239,28 @@
      * @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_ANY} for any tags, use
-     *            {@link NetworkStats.Bucket#TAG_ALL} to aggregate over tags.
+     * @param tag TAG of interest. Use {@link NetworkStats.Bucket#TAG_NONE} for no tags.
      * @return Statistics object or null if permissions are insufficient or error happened during
      *         statistics collection.
      */
     public NetworkStats queryDetailsForUidTag(int networkType, String subscriberId,
-            long startTime, long endTime, int uid, int tag) throws SecurityException,
-            RemoteException {
-        NetworkTemplate template = createTemplate(networkType, subscriberId);
-        if (template == null) {
+            long startTime, long endTime, int uid, int tag) {
+        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, startTime, endTime);
-        result.startHistoryEnumeration(uid, tag);
+        try {
+            result = new NetworkStats(mContext, template, startTime, endTime);
+            result.startHistoryEnumeration(uid, tag);
+        } catch (RemoteException e) {
+            Log.e(TAG, "Error while querying stats for uid=" + uid + " tag=" + tag, e);
+            return null;
+        }
 
         return result;
     }
@@ -280,7 +270,7 @@
      * calling user. Result is aggregated over state but not aggregated over time or uid. 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_ALL} and roaming is going to be
+     * tag {@link NetworkStats.Bucket#TAG_NONE} 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
@@ -299,44 +289,59 @@
      */
     public NetworkStats queryDetails(int networkType, String subscriberId, long startTime,
             long endTime) throws SecurityException, RemoteException {
-        NetworkTemplate template = createTemplate(networkType, subscriberId);
-        if (template == null) {
+        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, startTime, endTime);
         result.startUserUidEnumeration();
         return result;
     }
 
+    /** @removed */
+    public void registerDataUsageCallback(DataUsagePolicy policy, DataUsageCallback callback,
+                @Nullable Handler handler) {}
+
+    /** @removed */
+    public void registerDataUsageCallback(DataUsagePolicy policy, UsageCallback callback,
+                @Nullable Handler handler) {}
+
+    /** @removed */
+    public void unregisterDataUsageCallback(DataUsageCallback callback) {}
+
     /**
-     * Registers to receive notifications about data usage on specified networks and uids.
-     * The callbacks will continue to be called as long as the process is live or
-     * {@link #unregisterDataUsageCallback} is called.
+     * Registers to receive notifications about data usage on specified networks.
      *
-     * @param policy {@link DataUsagePolicy} describing this request.
-     * @param callback The {@link DataUsageCallback} that the system will call when data usage
-     *            has exceeded the specified threshold.
+     * #see registerUsageCallback(int, String[], long, UsageCallback, Handler)
      */
-    public void registerDataUsageCallback(DataUsagePolicy policy, DataUsageCallback callback) {
-        registerDataUsageCallback(policy, callback, null /* handler */);
+    public void registerUsageCallback(int networkType, String subscriberId, long thresholdBytes,
+            UsageCallback callback) {
+        registerUsageCallback(networkType, subscriberId, thresholdBytes, null /* handler */);
     }
 
     /**
-     * Registers to receive notifications about data usage on specified networks and uids.
-     * The callbacks will continue to be called as long as the process is live or
-     * {@link #unregisterDataUsageCallback} is called.
+     * Registers to receive notifications about data usage on specified networks.
      *
-     * @param policy {@link DataUsagePolicy} describing this request.
-     * @param callback The {@link DataUsageCallback} that the system will call when data usage
+     * <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.
+     * @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 registerDataUsageCallback(DataUsagePolicy policy, DataUsageCallback callback,
-                @Nullable Handler handler) {
-        checkNotNull(policy, "DataUsagePolicy cannot be null");
-        checkNotNull(callback, "DataUsageCallback cannot be null");
+    public void registerUsageCallback(int networkType, String subscriberId, long thresholdBytes,
+            UsageCallback callback, @Nullable Handler handler) {
+        checkNotNull(callback, "UsageCallback cannot be null");
 
         final Looper looper;
         if (handler == null) {
@@ -345,62 +350,72 @@
             looper = handler.getLooper();
         }
 
-        if (DBG) Log.d(TAG, "registerDataUsageCallback called with " + policy);
-
-        NetworkTemplate[] templates;
-        if (policy.subscriberIds == null || policy.subscriberIds.length == 0) {
-            templates = new NetworkTemplate[1];
-            templates[0] = createTemplate(policy.networkType, null /* subscriberId */);
-        } else {
-            templates = new NetworkTemplate[policy.subscriberIds.length];
-            for (int i = 0; i < policy.subscriberIds.length; i++) {
-                templates[i] = createTemplate(policy.networkType, policy.subscriberIds[i]);
-            }
+        if (DBG) {
+            Log.d(TAG, "registerUsageCallback called with: {"
+                + " networkType=" + networkType
+                + " subscriberId=" + subscriberId
+                + " thresholdBytes=" + thresholdBytes
+                + " }");
         }
+
+        NetworkTemplate template = createTemplate(networkType, subscriberId);
         DataUsageRequest request = new DataUsageRequest(DataUsageRequest.REQUEST_ID_UNSET,
-                templates, policy.uids, policy.thresholdInBytes);
+                template, thresholdBytes);
         try {
-            CallbackHandler callbackHandler = new CallbackHandler(looper, callback);
-            callback.request = mService.registerDataUsageCallback(
+            CallbackHandler callbackHandler = new CallbackHandler(looper, networkType,
+                    subscriberId, callback);
+            callback.request = mService.registerUsageCallback(
                     mContext.getOpPackageName(), request, new Messenger(callbackHandler),
                     new Binder());
-            if (DBG) Log.d(TAG, "registerDataUsageCallback returned " + callback.request);
+            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();
         }
     }
 
     /**
      * Unregisters callbacks on data usage.
      *
-     * @param callback The {@link DataUsageCallback} used when registering.
+     * @param callback The {@link UsageCallback} used when registering.
      */
-    public void unregisterDataUsageCallback(DataUsageCallback callback) {
+    public void unregisterUsageCallback(UsageCallback callback) {
         if (callback == null || callback.request == null
                 || callback.request.requestId == DataUsageRequest.REQUEST_ID_UNSET) {
-            throw new IllegalArgumentException("Invalid DataUsageCallback");
+            throw new IllegalArgumentException("Invalid UsageCallback");
         }
         try {
-            mService.unregisterDataUsageRequest(callback.request);
+            mService.unregisterUsageRequest(callback.request);
         } catch (RemoteException e) {
             if (DBG) Log.d(TAG, "Remote exception when unregistering callback");
+            throw e.rethrowFromSystemServer();
         }
     }
 
-    /**
-     * Base class for data usage callbacks. Should be extended by applications wanting
-     * notifications.
-     */
-    public static class DataUsageCallback {
-        /**
-         * Called when data usage has reached the given policy threshold.
-         */
+    /** @removed */
+    public static abstract class DataUsageCallback {
+        /** @removed */
+        @Deprecated
         public void onLimitReached() {}
+    }
 
+    /**
+     * 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;
     }
 
@@ -414,18 +429,24 @@
                 template = NetworkTemplate.buildTemplateWifiWildcard();
                 } break;
             default: {
-                Log.w(TAG, "Cannot create template for network type " + networkType
-                        + ", subscriberId '" + NetworkIdentity.scrubSubscriberId(subscriberId) +
-                        "'.");
+                throw new IllegalArgumentException("Cannot create template for network type "
+                        + networkType + ", subscriberId '"
+                        + NetworkIdentity.scrubSubscriberId(subscriberId) + "'.");
             }
         }
         return template;
     }
 
     private static class CallbackHandler extends Handler {
-        private DataUsageCallback mCallback;
-        CallbackHandler(Looper looper, DataUsageCallback callback) {
+        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;
         }
 
@@ -437,7 +458,7 @@
             switch (message.what) {
                 case CALLBACK_LIMIT_REACHED: {
                     if (mCallback != null) {
-                        mCallback.onLimitReached();
+                        mCallback.onThresholdReached(mNetworkType, mSubscriberId);
                     } else {
                         Log.e(TAG, "limit reached with released callback for " + request);
                     }
diff --git a/core/java/android/net/DataUsageRequest.java b/core/java/android/net/DataUsageRequest.java
index 8526584..ac9a5a3 100644
--- a/core/java/android/net/DataUsageRequest.java
+++ b/core/java/android/net/DataUsageRequest.java
@@ -20,7 +20,6 @@
 import android.os.Parcel;
 import android.os.Parcelable;
 
-import java.util.Arrays;
 import java.util.Objects;
 
 /**
@@ -28,56 +27,33 @@
  * {@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 {
 
-    /**
-     * @hide
-     */
     public static final String PARCELABLE_KEY = "DataUsageRequest";
-
-    /**
-     * @hide
-     */
     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.
-     * @hide
      */
     public final int requestId;
 
     /**
-     * Set of {@link NetworkTemplate}s describing the networks to monitor.
-     * @hide
+     * {@link NetworkTemplate} describing the network to monitor.
      */
-    public final NetworkTemplate[] templates;
-
-    /**
-     * Set of UIDs of which to monitor data usage.
-     *
-     * <p>If not {@code null}, the caller will be notified when any of the uids exceed
-     * the given threshold. If {@code null} all uids for which the calling process has access
-     * to stats will be monitored.
-     * @hide
-     */
-    public final int[] uids;
+    public final NetworkTemplate template;
 
     /**
      * Threshold in bytes to be notified on.
-     * @hide
      */
     public final long thresholdInBytes;
 
-    /**
-     * @hide
-     */
-    public DataUsageRequest(int requestId, NetworkTemplate[] templates, int[] uids,
-                long thresholdInBytes) {
+    public DataUsageRequest(int requestId, NetworkTemplate template, long thresholdInBytes) {
         this.requestId = requestId;
-        this.templates = templates;
-        this.uids = uids;
+        this.template = template;
         this.thresholdInBytes = thresholdInBytes;
     }
 
@@ -89,8 +65,7 @@
     @Override
     public void writeToParcel(Parcel dest, int flags) {
         dest.writeInt(requestId);
-        dest.writeTypedArray(templates, flags);
-        dest.writeIntArray(uids);
+        dest.writeParcelable(template, flags);
         dest.writeLong(thresholdInBytes);
     }
 
@@ -99,11 +74,10 @@
                 @Override
                 public DataUsageRequest createFromParcel(Parcel in) {
                     int requestId = in.readInt();
-                    NetworkTemplate[] templates = in.createTypedArray(NetworkTemplate.CREATOR);
-                    int[] uids = in.createIntArray();
+                    NetworkTemplate template = in.readParcelable(null);
                     long thresholdInBytes = in.readLong();
-                    DataUsageRequest result = new DataUsageRequest(requestId,
-                            templates, uids, thresholdInBytes);
+                    DataUsageRequest result = new DataUsageRequest(requestId, template,
+                            thresholdInBytes);
                     return result;
                 }
 
@@ -116,8 +90,7 @@
     @Override
     public String toString() {
         return "DataUsageRequest [ requestId=" + requestId
-                + ", networkTemplates=" + Arrays.toString(templates)
-                + ", uids=" + Arrays.toString(uids)
+                + ", networkTemplate=" + template
                 + ", thresholdInBytes=" + thresholdInBytes + " ]";
     }
 
@@ -126,23 +99,13 @@
         if (obj instanceof DataUsageRequest == false) return false;
         DataUsageRequest that = (DataUsageRequest) obj;
         return that.requestId == this.requestId
-                && Arrays.deepEquals(that.templates, this.templates)
-                && Arrays.equals(that.uids, this.uids)
+                && Objects.equals(that.template, this.template)
                 && that.thresholdInBytes == this.thresholdInBytes;
     }
 
     @Override
     public int hashCode() {
-        // Start with a non-zero constant.
-        int result = 17;
-
-        // Include a hash for each field.
-        result = 31 * result + requestId;
-        result = 31 * result + Arrays.deepHashCode(templates);
-        result = 31 * result + Arrays.hashCode(uids);
-        result = 31 * result + (int) (thresholdInBytes ^ (thresholdInBytes >>> 32));
-
-        return result;
+        return Objects.hash(requestId, template, thresholdInBytes);
    }
 
 }
diff --git a/core/java/android/net/INetworkStatsService.aidl b/core/java/android/net/INetworkStatsService.aidl
index 2eea940..e693009 100644
--- a/core/java/android/net/INetworkStatsService.aidl
+++ b/core/java/android/net/INetworkStatsService.aidl
@@ -61,10 +61,10 @@
     void advisePersistThreshold(long thresholdBytes);
 
     /** Registers a callback on data usage. */
-    DataUsageRequest registerDataUsageCallback(String callingPackage,
+    DataUsageRequest registerUsageCallback(String callingPackage,
             in DataUsageRequest request, in Messenger messenger, in IBinder binder);
 
     /** Unregisters a callback on data usage. */
-    void unregisterDataUsageRequest(in DataUsageRequest request);
+    void unregisterUsageRequest(in DataUsageRequest request);
 
 }
diff --git a/services/core/java/com/android/server/net/NetworkStatsObservers.java b/services/core/java/com/android/server/net/NetworkStatsObservers.java
index 6f781b3..230c2e9 100644
--- a/services/core/java/com/android/server/net/NetworkStatsObservers.java
+++ b/services/core/java/com/android/server/net/NetworkStatsObservers.java
@@ -81,8 +81,6 @@
      */
     public DataUsageRequest register(DataUsageRequest inputRequest, Messenger messenger,
                 IBinder binder, int callingUid, @NetworkStatsAccess.Level int accessLevel) {
-        checkVisibilityUids(callingUid, accessLevel, inputRequest.uids);
-
         DataUsageRequest request = buildRequest(inputRequest);
         RequestInfo requestInfo = buildRequestInfo(request, messenger, binder, callingUid,
                 accessLevel);
@@ -211,14 +209,13 @@
                     + ". Overriding to a safer default of " + thresholdInBytes + " bytes");
         }
         return new DataUsageRequest(mNextDataUsageRequestId.incrementAndGet(),
-                request.templates, request.uids, thresholdInBytes);
+                request.template, thresholdInBytes);
     }
 
     private RequestInfo buildRequestInfo(DataUsageRequest request,
                 Messenger messenger, IBinder binder, int callingUid,
                 @NetworkStatsAccess.Level int accessLevel) {
-        if (accessLevel <= NetworkStatsAccess.Level.USER
-                || request.uids != null && request.uids.length > 0) {
+        if (accessLevel <= NetworkStatsAccess.Level.USER) {
             return new UserUsageRequestInfo(this, request, messenger, binder, callingUid,
                     accessLevel);
         } else {
@@ -229,19 +226,6 @@
         }
     }
 
-    private void checkVisibilityUids(int callingUid, @NetworkStatsAccess.Level int accessLevel,
-                int[] uids) {
-        if (uids == null) {
-            return;
-        }
-        for (int i = 0; i < uids.length; i++) {
-            if (!NetworkStatsAccess.isAccessibleToUser(uids[i], callingUid, accessLevel)) {
-                throw new SecurityException("Caller " + callingUid + " cannot monitor network stats"
-                        + " for uid " + uids[i] + " with accessLevel " + accessLevel);
-            }
-        }
-    }
-
     /**
      * Tracks information relevant to a data usage observer.
      * It will notice when the calling process dies so we can self-expire.
@@ -359,15 +343,13 @@
 
         @Override
         protected boolean checkStats() {
-            for (int i = 0; i < mRequest.templates.length; i++) {
-                long bytesSoFar = getTotalBytesForNetwork(mRequest.templates[i]);
-                if (LOGV) {
-                    Slog.v(TAG, bytesSoFar + " bytes so far since notification for "
-                            + mRequest.templates[i]);
-                }
-                if (bytesSoFar > mRequest.thresholdInBytes) {
-                    return true;
-                }
+            long bytesSoFar = getTotalBytesForNetwork(mRequest.template);
+            if (LOGV) {
+                Slog.v(TAG, bytesSoFar + " bytes so far since notification for "
+                        + mRequest.template);
+            }
+            if (bytesSoFar > mRequest.thresholdInBytes) {
+                return true;
             }
             return false;
         }
@@ -405,20 +387,17 @@
 
         @Override
         protected boolean checkStats() {
-            int[] uidsToMonitor = getUidsToMonitor();
+            int[] uidsToMonitor = mCollection.getRelevantUids(mAccessLevel, mCallingUid);
 
-            for (int i = 0; i < mRequest.templates.length; i++) {
-                for (int j = 0; j < uidsToMonitor.length; j++) {
-                    long bytesSoFar = getTotalBytesForNetworkUid(mRequest.templates[i],
-                            uidsToMonitor[j]);
+            for (int i = 0; i < uidsToMonitor.length; i++) {
+                long bytesSoFar = getTotalBytesForNetworkUid(mRequest.template, uidsToMonitor[i]);
 
-                    if (LOGV) {
-                        Slog.v(TAG, bytesSoFar + " bytes so far since notification for "
-                                + mRequest.templates[i] + " for uid=" + uidsToMonitor[j]);
-                    }
-                    if (bytesSoFar > mRequest.thresholdInBytes) {
-                        return true;
-                    }
+                if (LOGV) {
+                    Slog.v(TAG, bytesSoFar + " bytes so far since notification for "
+                            + mRequest.template + " for uid=" + uidsToMonitor[i]);
+                }
+                if (bytesSoFar > mRequest.thresholdInBytes) {
+                    return true;
                 }
             }
             return false;
@@ -453,21 +432,6 @@
                 return 0;
             }
         }
-
-        private int[] getUidsToMonitor() {
-            if (mRequest.uids == null || mRequest.uids.length == 0) {
-                return mCollection.getRelevantUids(mAccessLevel, mCallingUid);
-            }
-            // Pick only uids from the request that are currently accessible to the user
-            IntArray accessibleUids = new IntArray(mRequest.uids.length);
-            for (int i = 0; i < mRequest.uids.length; i++) {
-                int uid = mRequest.uids[i];
-                if (NetworkStatsAccess.isAccessibleToUser(uid, mCallingUid, mAccessLevel)) {
-                    accessibleUids.add(uid);
-                }
-            }
-            return accessibleUids.toArray();
-        }
     }
 
     private static class StatsContext {
diff --git a/services/core/java/com/android/server/net/NetworkStatsService.java b/services/core/java/com/android/server/net/NetworkStatsService.java
index 2c2e9b9..8610fa1 100644
--- a/services/core/java/com/android/server/net/NetworkStatsService.java
+++ b/services/core/java/com/android/server/net/NetworkStatsService.java
@@ -578,9 +578,12 @@
                 if (tag == TAG_NONE) {
                     return getUidComplete().getHistory(template, uid, set, tag, fields, start, end,
                             accessLevel);
-                } else {
+                } else if (uid == Binder.getCallingUid()) {
                     return getUidTagComplete().getHistory(template, uid, set, tag, fields,
                             start, end, accessLevel);
+                } else {
+                    throw new SecurityException("Calling package " + mCallingPackage
+                            + " cannot access tag information from a different uid");
                 }
             }
 
@@ -761,12 +764,11 @@
     }
 
     @Override
-    public DataUsageRequest registerDataUsageCallback(String callingPackage,
+    public DataUsageRequest registerUsageCallback(String callingPackage,
                 DataUsageRequest request, Messenger messenger, IBinder binder) {
         checkNotNull(callingPackage, "calling package is null");
         checkNotNull(request, "DataUsageRequest is null");
-        checkNotNull(request.templates, "NetworkTemplate is null");
-        checkArgument(request.templates.length > 0);
+        checkNotNull(request.template, "NetworkTemplate is null");
         checkNotNull(messenger, "messenger is null");
         checkNotNull(binder, "binder is null");
 
@@ -788,7 +790,7 @@
    }
 
     @Override
-    public void unregisterDataUsageRequest(DataUsageRequest request) {
+    public void unregisterUsageRequest(DataUsageRequest request) {
         checkNotNull(request, "DataUsageRequest is null");
 
         int callingUid = Binder.getCallingUid();