diff --git a/framework/Android.bp b/framework/Android.bp
index 017ff51..5b33328 100644
--- a/framework/Android.bp
+++ b/framework/Android.bp
@@ -25,6 +25,7 @@
 
 java_library {
     name: "framework-connectivity-protos",
+    sdk_version: "module_current",
     proto: {
         type: "nano",
     },
@@ -82,8 +83,7 @@
     name: "framework-connectivity",
     api_only: true,
     defaults: ["framework-module-defaults"],
-    // TODO: build against module API
-    platform_apis: true,
+    installable: true,
     srcs: [
         ":framework-connectivity-sources",
     ],
@@ -100,18 +100,15 @@
     libs: [
         "unsupportedappusage",
     ],
-    permitted_packages: ["android.net", "com.android.connectivity.aidl"],
+    permitted_packages: [
+        "android.net",
+        "com.android.connectivity.aidl",
+    ],
 }
 
 java_library {
     name: "framework-connectivity.impl",
-    // Instead of building against private API (framework.jar),
-    // build against core_platform + framework-minus-apex + module
-    // stub libs. This allows framework.jar to depend on this library,
-    // so it can be part of the private API until all clients have been migrated.
-    // TODO: just build against module_api, and remove this jar from
-    // the private API.
-    sdk_version: "core_platform",
+    sdk_version: "module_current",
     srcs: [
         ":framework-connectivity-sources",
     ],
@@ -122,10 +119,10 @@
         ],
     },
     libs: [
-        "framework-minus-apex",
-        // TODO: just framework-tethering, framework-wifi when building against module_api
-        "framework-tethering.stubs.module_lib",
-        "framework-wifi.stubs.module_lib",
+        // TODO (b/183097033) remove once module_current includes core_current
+        "stable.core.platform.api.stubs",
+        "framework-tethering",
+        "framework-wifi",
         "unsupportedappusage",
         "ServiceConnectivityResources",
     ],
@@ -136,5 +133,8 @@
     jarjar_rules: "jarjar-rules.txt",
     apex_available: ["com.android.tethering"],
     installable: true,
-    permitted_packages: ["android.net", "com.android.connectivity.aidl"],
+    permitted_packages: [
+        "android.net",
+        "com.android.connectivity.aidl",
+    ],
 }
diff --git a/framework/aidl-export/android/net/NetworkScore.aidl b/framework/aidl-export/android/net/NetworkScore.aidl
new file mode 100644
index 0000000..af12dcf
--- /dev/null
+++ b/framework/aidl-export/android/net/NetworkScore.aidl
@@ -0,0 +1,20 @@
+/**
+ * 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;
+
+parcelable NetworkScore;
+
diff --git a/framework/api/module-lib-current.txt b/framework/api/module-lib-current.txt
index 8e9e6ac..b1d2b97 100644
--- a/framework/api/module-lib-current.txt
+++ b/framework/api/module-lib-current.txt
@@ -39,9 +39,18 @@
   }
 
   public final class NetworkCapabilities implements android.os.Parcelable {
+    method @Nullable public java.util.Set<android.util.Range<java.lang.Integer>> getUids();
     field public static final int TRANSPORT_TEST = 7; // 0x7
   }
 
+  public static final class NetworkCapabilities.Builder {
+    method @NonNull public android.net.NetworkCapabilities.Builder setUids(@Nullable java.util.Set<android.util.Range<java.lang.Integer>>);
+  }
+
+  public static class NetworkRequest.Builder {
+    method @NonNull public android.net.NetworkRequest.Builder setUids(@Nullable java.util.Set<android.util.Range<java.lang.Integer>>);
+  }
+
   public class ParseException extends java.lang.RuntimeException {
     ctor public ParseException(@NonNull String);
     ctor public ParseException(@NonNull String, @NonNull Throwable);
diff --git a/framework/src/android/net/ConnectivityDiagnosticsManager.java b/framework/src/android/net/ConnectivityDiagnosticsManager.java
index 5234494..3598ebc 100644
--- a/framework/src/android/net/ConnectivityDiagnosticsManager.java
+++ b/framework/src/android/net/ConnectivityDiagnosticsManager.java
@@ -28,7 +28,6 @@
 import android.os.RemoteException;
 
 import com.android.internal.annotations.VisibleForTesting;
-import com.android.internal.util.Preconditions;
 
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
@@ -70,8 +69,8 @@
 
     /** @hide */
     public ConnectivityDiagnosticsManager(Context context, IConnectivityManager service) {
-        mContext = Preconditions.checkNotNull(context, "missing context");
-        mService = Preconditions.checkNotNull(service, "missing IConnectivityManager");
+        mContext = Objects.requireNonNull(context, "missing context");
+        mService = Objects.requireNonNull(service, "missing IConnectivityManager");
     }
 
     /** @hide */
diff --git a/framework/src/android/net/ConnectivityManager.java b/framework/src/android/net/ConnectivityManager.java
index a5e38fa..ff1e78f 100644
--- a/framework/src/android/net/ConnectivityManager.java
+++ b/framework/src/android/net/ConnectivityManager.java
@@ -75,7 +75,6 @@
 
 import com.android.connectivity.aidl.INetworkAgent;
 import com.android.internal.annotations.GuardedBy;
-import com.android.internal.util.Preconditions;
 
 import libcore.net.event.NetworkEventDispatcher;
 
@@ -1778,7 +1777,9 @@
         // Map from type to transports.
         final int NOT_FOUND = -1;
         final int transport = sLegacyTypeToTransport.get(type, NOT_FOUND);
-        Preconditions.checkArgument(transport != NOT_FOUND, "unknown legacy type: " + type);
+        if (transport == NOT_FOUND) {
+            throw new IllegalArgumentException("unknown legacy type: " + type);
+        }
         nc.addTransportType(transport);
 
         // Map from type to capabilities.
@@ -1883,8 +1884,8 @@
         }
 
         private PacketKeepalive(Network network, PacketKeepaliveCallback callback) {
-            Preconditions.checkNotNull(network, "network cannot be null");
-            Preconditions.checkNotNull(callback, "callback cannot be null");
+            Objects.requireNonNull(network, "network cannot be null");
+            Objects.requireNonNull(callback, "callback cannot be null");
             mNetwork = network;
             mExecutor = Executors.newSingleThreadExecutor();
             mCallback = new ISocketKeepaliveCallback.Stub() {
@@ -2259,7 +2260,9 @@
      */
     public void removeDefaultNetworkActiveListener(@NonNull OnNetworkActiveListener l) {
         INetworkActivityListener rl = mNetworkActivityListeners.get(l);
-        Preconditions.checkArgument(rl != null, "Listener was not registered.");
+        if (rl == null) {
+            throw new IllegalArgumentException("Listener was not registered.");
+        }
         try {
             mService.registerNetworkActivityListener(rl);
         } catch (RemoteException e) {
@@ -2287,8 +2290,8 @@
      * {@hide}
      */
     public ConnectivityManager(Context context, IConnectivityManager service) {
-        mContext = Preconditions.checkNotNull(context, "missing context");
-        mService = Preconditions.checkNotNull(service, "missing IConnectivityManager");
+        mContext = Objects.requireNonNull(context, "missing context");
+        mService = Objects.requireNonNull(service, "missing IConnectivityManager");
         mTetheringManager = (TetheringManager) mContext.getSystemService(Context.TETHERING_SERVICE);
         sInstance = this;
     }
@@ -2555,7 +2558,7 @@
     @RequiresPermission(android.Manifest.permission.TETHER_PRIVILEGED)
     public void startTethering(int type, boolean showProvisioningUi,
             final OnStartTetheringCallback callback, Handler handler) {
-        Preconditions.checkNotNull(callback, "OnStartTetheringCallback cannot be null.");
+        Objects.requireNonNull(callback, "OnStartTetheringCallback cannot be null.");
 
         final Executor executor = new Executor() {
             @Override
@@ -2648,7 +2651,7 @@
     public void registerTetheringEventCallback(
             @NonNull @CallbackExecutor Executor executor,
             @NonNull final OnTetheringEventCallback callback) {
-        Preconditions.checkNotNull(callback, "OnTetheringEventCallback cannot be null.");
+        Objects.requireNonNull(callback, "OnTetheringEventCallback cannot be null.");
 
         final TetheringEventCallback tetherCallback =
                 new TetheringEventCallback() {
@@ -2946,7 +2949,7 @@
     public void getLatestTetheringEntitlementResult(int type, boolean showEntitlementUi,
             @NonNull @CallbackExecutor Executor executor,
             @NonNull final OnTetheringEntitlementResultListener listener) {
-        Preconditions.checkNotNull(listener, "TetheringEntitlementResultListener cannot be null.");
+        Objects.requireNonNull(listener, "TetheringEntitlementResultListener cannot be null.");
         ResultReceiver wrappedListener = new ResultReceiver(null) {
             @Override
             protected void onReceiveResult(int resultCode, Bundle resultData) {
@@ -3319,7 +3322,9 @@
         }
 
         public NetworkCallback(@Flag int flags) {
-            Preconditions.checkArgument((flags & VALID_FLAGS) == flags);
+            if ((flags & VALID_FLAGS) != flags) {
+                throw new IllegalArgumentException("Invalid flags");
+            }
             mFlags = flags;
         }
 
@@ -3605,7 +3610,7 @@
         }
 
         CallbackHandler(Handler handler) {
-            this(Preconditions.checkNotNull(handler, "Handler cannot be null.").getLooper());
+            this(Objects.requireNonNull(handler, "Handler cannot be null.").getLooper());
         }
 
         @Override
@@ -3703,9 +3708,9 @@
             int timeoutMs, NetworkRequest.Type reqType, int legacyType, CallbackHandler handler) {
         printStackTrace();
         checkCallbackNotNull(callback);
-        Preconditions.checkArgument(
-                reqType == TRACK_DEFAULT || reqType == TRACK_SYSTEM_DEFAULT || need != null,
-                "null NetworkCapabilities");
+        if (reqType != TRACK_DEFAULT && reqType != TRACK_SYSTEM_DEFAULT && need == null) {
+            throw new IllegalArgumentException("null NetworkCapabilities");
+        }
         final NetworkRequest request;
         final String callingPackageName = mContext.getOpPackageName();
         try {
@@ -4052,15 +4057,17 @@
     }
 
     private static void checkPendingIntentNotNull(PendingIntent intent) {
-        Preconditions.checkNotNull(intent, "PendingIntent cannot be null.");
+        Objects.requireNonNull(intent, "PendingIntent cannot be null.");
     }
 
     private static void checkCallbackNotNull(NetworkCallback callback) {
-        Preconditions.checkNotNull(callback, "null NetworkCallback");
+        Objects.requireNonNull(callback, "null NetworkCallback");
     }
 
     private static void checkTimeout(int timeoutMs) {
-        Preconditions.checkArgumentPositive(timeoutMs, "timeoutMs must be strictly positive.");
+        if (timeoutMs <= 0) {
+            throw new IllegalArgumentException("timeoutMs must be strictly positive.");
+        }
     }
 
     /**
@@ -4340,8 +4347,9 @@
         // Find all requests associated to this callback and stop callback triggers immediately.
         // Callback is reusable immediately. http://b/20701525, http://b/35921499.
         synchronized (sCallbacks) {
-            Preconditions.checkArgument(networkCallback.networkRequest != null,
-                    "NetworkCallback was not registered");
+            if (networkCallback.networkRequest == null) {
+                throw new IllegalArgumentException("NetworkCallback was not registered");
+            }
             if (networkCallback.networkRequest == ALREADY_UNREGISTERED) {
                 Log.d(TAG, "NetworkCallback was already unregistered");
                 return;
@@ -4662,7 +4670,7 @@
                 Log.e(TAG, "Can't set proxy properties", e);
             }
             // Must flush DNS cache as new network may have different DNS resolutions.
-            InetAddress.clearDnsCache();
+            InetAddressCompat.clearDnsCache();
             // Must flush socket pool as idle sockets will be bound to previous network and may
             // cause subsequent fetches to be performed on old network.
             NetworkEventDispatcher.getInstance().onNetworkConfigurationChanged();
diff --git a/framework/src/android/net/IOnCompleteListener.aidl b/framework/src/android/net/IOnCompleteListener.aidl
new file mode 100644
index 0000000..4bb89f6
--- /dev/null
+++ b/framework/src/android/net/IOnCompleteListener.aidl
@@ -0,0 +1,23 @@
+/**
+ *
+ * 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;
+
+/** @hide */
+oneway interface IOnCompleteListener {
+    void onComplete();
+}
diff --git a/framework/src/android/net/InetAddressCompat.java b/framework/src/android/net/InetAddressCompat.java
new file mode 100644
index 0000000..8404441
--- /dev/null
+++ b/framework/src/android/net/InetAddressCompat.java
@@ -0,0 +1,76 @@
+/*
+ * 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 android.util.Log;
+
+import java.lang.reflect.InvocationTargetException;
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
+/**
+ * Compatibility utility for InetAddress core platform APIs.
+ *
+ * Connectivity has access to such APIs, but they are not part of the module_current stubs yet
+ * (only core_current). Most stable core platform APIs are included manually in the connectivity
+ * build rules, but because InetAddress is also part of the base java SDK that is earlier on the
+ * classpath, the extra core platform APIs are not seen.
+ *
+ * TODO (b/183097033): remove this utility as soon as core_current is part of module_current
+ * @hide
+ */
+public class InetAddressCompat {
+
+    /**
+     * @see InetAddress#clearDnsCache()
+     */
+    public static void clearDnsCache() {
+        try {
+            InetAddress.class.getMethod("clearDnsCache").invoke(null);
+        } catch (IllegalAccessException | InvocationTargetException | NoSuchMethodException e) {
+            Log.wtf(InetAddressCompat.class.getSimpleName(), "Error clearing DNS cache", e);
+        }
+    }
+
+    /**
+     * @see InetAddress#getAllByNameOnNet(String, int)
+     */
+    public static InetAddress[] getAllByNameOnNet(String host, int netId) throws
+            UnknownHostException {
+        try {
+            return (InetAddress[]) InetAddress.class.getMethod("getAllByNameOnNet",
+                    String.class, int.class).invoke(null, host, netId);
+        } catch (IllegalAccessException | InvocationTargetException | NoSuchMethodException e) {
+            Log.wtf(InetAddressCompat.class.getSimpleName(), "Error calling getAllByNameOnNet", e);
+            throw new IllegalStateException("Error querying via getAllNameOnNet", e);
+        }
+    }
+
+    /**
+     * @see InetAddress#getByNameOnNet(String, int)
+     */
+    public static InetAddress getByNameOnNet(String host, int netId) throws
+            UnknownHostException {
+        try {
+            return (InetAddress) InetAddress.class.getMethod("getByNameOnNet",
+                    String.class, int.class).invoke(null, host, netId);
+        } catch (IllegalAccessException | InvocationTargetException | NoSuchMethodException e) {
+            Log.wtf(InetAddressCompat.class.getSimpleName(), "Error calling getAllByNameOnNet", e);
+            throw new IllegalStateException("Error querying via getByNameOnNet", e);
+        }
+    }
+}
diff --git a/framework/src/android/net/MacAddress.java b/framework/src/android/net/MacAddress.java
index c83c23a..26a504a 100644
--- a/framework/src/android/net/MacAddress.java
+++ b/framework/src/android/net/MacAddress.java
@@ -25,7 +25,6 @@
 import android.os.Parcel;
 import android.os.Parcelable;
 
-import com.android.internal.util.Preconditions;
 import com.android.net.module.util.MacAddressUtils;
 
 import java.lang.annotation.Retention;
@@ -34,6 +33,7 @@
 import java.net.UnknownHostException;
 import java.security.SecureRandom;
 import java.util.Arrays;
+import java.util.Objects;
 
 /**
  * Representation of a MAC address.
@@ -229,7 +229,7 @@
      * @hide
      */
     public static @NonNull byte[] byteAddrFromStringAddr(String addr) {
-        Preconditions.checkNotNull(addr);
+        Objects.requireNonNull(addr);
         String[] parts = addr.split(":");
         if (parts.length != ETHER_ADDR_LEN) {
             throw new IllegalArgumentException(addr + " was not a valid MAC address");
@@ -275,7 +275,7 @@
     // Internal conversion function equivalent to longAddrFromByteAddr(byteAddrFromStringAddr(addr))
     // that avoids the allocation of an intermediary byte[].
     private static long longAddrFromStringAddr(String addr) {
-        Preconditions.checkNotNull(addr);
+        Objects.requireNonNull(addr);
         String[] parts = addr.split(":");
         if (parts.length != ETHER_ADDR_LEN) {
             throw new IllegalArgumentException(addr + " was not a valid MAC address");
@@ -364,8 +364,8 @@
      *
      */
     public boolean matches(@NonNull MacAddress baseAddress, @NonNull MacAddress mask) {
-        Preconditions.checkNotNull(baseAddress);
-        Preconditions.checkNotNull(mask);
+        Objects.requireNonNull(baseAddress);
+        Objects.requireNonNull(mask);
         return (mAddr & mask.mAddr) == (baseAddress.mAddr & mask.mAddr);
     }
 
diff --git a/framework/src/android/net/Network.java b/framework/src/android/net/Network.java
index 7245db3..0741414 100644
--- a/framework/src/android/net/Network.java
+++ b/framework/src/android/net/Network.java
@@ -142,7 +142,7 @@
      * @throws UnknownHostException if the address lookup fails.
      */
     public InetAddress[] getAllByName(String host) throws UnknownHostException {
-        return InetAddress.getAllByNameOnNet(host, getNetIdForResolv());
+        return InetAddressCompat.getAllByNameOnNet(host, getNetIdForResolv());
     }
 
     /**
@@ -155,7 +155,7 @@
      *             if the address lookup fails.
      */
     public InetAddress getByName(String host) throws UnknownHostException {
-        return InetAddress.getByNameOnNet(host, getNetIdForResolv());
+        return InetAddressCompat.getByNameOnNet(host, getNetIdForResolv());
     }
 
     /**
diff --git a/framework/src/android/net/NetworkCapabilities.java b/framework/src/android/net/NetworkCapabilities.java
index 058f3c9..7135ba8 100644
--- a/framework/src/android/net/NetworkCapabilities.java
+++ b/framework/src/android/net/NetworkCapabilities.java
@@ -22,6 +22,7 @@
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.annotation.RequiresPermission;
+import android.annotation.SuppressLint;
 import android.annotation.SystemApi;
 import android.compat.annotation.UnsupportedAppUsage;
 import android.net.ConnectivityManager.NetworkCallback;
@@ -32,10 +33,10 @@
 import android.os.Process;
 import android.text.TextUtils;
 import android.util.ArraySet;
+import android.util.Range;
 import android.util.proto.ProtoOutputStream;
 
 import com.android.internal.annotations.VisibleForTesting;
-import com.android.internal.util.Preconditions;
 import com.android.net.module.util.CollectionUtils;
 import com.android.net.module.util.NetworkCapabilitiesUtils;
 
@@ -153,7 +154,7 @@
             setTransportInfo(null);
         }
         mSignalStrength = nc.mSignalStrength;
-        setUids(nc.mUids); // Will make the defensive copy
+        mUids = (nc.mUids == null) ? null : new ArraySet<>(nc.mUids);
         setAdministratorUids(nc.getAdministratorUids());
         mOwnerUid = nc.mOwnerUid;
         mUnwantedNetworkCapabilities = nc.mUnwantedNetworkCapabilities;
@@ -1458,9 +1459,8 @@
      * @hide
      */
     public @NonNull NetworkCapabilities setSingleUid(int uid) {
-        final ArraySet<UidRange> identity = new ArraySet<>(1);
-        identity.add(new UidRange(uid, uid));
-        setUids(identity);
+        mUids = new ArraySet<>(1);
+        mUids.add(new UidRange(uid, uid));
         return this;
     }
 
@@ -1469,22 +1469,34 @@
      * This makes a copy of the set so that callers can't modify it after the call.
      * @hide
      */
-    public @NonNull NetworkCapabilities setUids(Set<UidRange> uids) {
-        if (null == uids) {
-            mUids = null;
-        } else {
-            mUids = new ArraySet<>(uids);
-        }
+    public @NonNull NetworkCapabilities setUids(@Nullable Set<Range<Integer>> uids) {
+        mUids = UidRange.fromIntRanges(uids);
         return this;
     }
 
     /**
      * Get the list of UIDs this network applies to.
      * This returns a copy of the set so that callers can't modify the original object.
+     *
+     * @return the list of UIDs this network applies to. If {@code null}, then the network applies
+     *         to all UIDs.
+     * @hide
+     */
+    @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
+    @SuppressLint("NullableCollection")
+    public @Nullable Set<Range<Integer>> getUids() {
+        return UidRange.toIntRanges(mUids);
+    }
+
+    /**
+     * Get the list of UIDs this network applies to.
+     * This returns a copy of the set so that callers can't modify the original object.
      * @hide
      */
-    public @Nullable Set<UidRange> getUids() {
-        return null == mUids ? null : new ArraySet<>(mUids);
+    public @Nullable Set<UidRange> getUidRanges() {
+        if (mUids == null) return null;
+
+        return new ArraySet<>(mUids);
     }
 
     /**
@@ -2099,8 +2111,9 @@
     }
 
     private static void checkValidTransportType(@Transport int transport) {
-        Preconditions.checkArgument(
-                isValidTransport(transport), "Invalid TransportType " + transport);
+        if (!isValidTransport(transport)) {
+            throw new IllegalArgumentException("Invalid TransportType " + transport);
+        }
     }
 
     private static boolean isValidCapability(@NetworkCapabilities.NetCapability int capability) {
@@ -2108,8 +2121,9 @@
     }
 
     private static void checkValidCapability(@NetworkCapabilities.NetCapability int capability) {
-        Preconditions.checkArgument(isValidCapability(capability),
-                "NetworkCapability " + capability + "out of range");
+        if (!isValidCapability(capability)) {
+            throw new IllegalArgumentException("NetworkCapability " + capability + "out of range");
+        }
     }
 
     /**
@@ -2655,6 +2669,21 @@
         }
 
         /**
+         * Set the list of UIDs this network applies to.
+         *
+         * @param uids the list of UIDs this network applies to, or {@code null} if this network
+         *             applies to all UIDs.
+         * @return this builder
+         * @hide
+         */
+        @NonNull
+        @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
+        public Builder setUids(@Nullable Set<Range<Integer>> uids) {
+            mCaps.setUids(uids);
+            return this;
+        }
+
+        /**
          * Builds the instance of the capabilities.
          *
          * @return the built instance of NetworkCapabilities.
diff --git a/framework/src/android/net/NetworkRequest.java b/framework/src/android/net/NetworkRequest.java
index dbe3ecc..cf131f0 100644
--- a/framework/src/android/net/NetworkRequest.java
+++ b/framework/src/android/net/NetworkRequest.java
@@ -36,6 +36,7 @@
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.annotation.RequiresPermission;
+import android.annotation.SuppressLint;
 import android.annotation.SystemApi;
 import android.compat.annotation.UnsupportedAppUsage;
 import android.net.NetworkCapabilities.NetCapability;
@@ -45,6 +46,7 @@
 import android.os.Parcelable;
 import android.os.Process;
 import android.text.TextUtils;
+import android.util.Range;
 import android.util.proto.ProtoOutputStream;
 
 import java.util.Arrays;
@@ -277,11 +279,14 @@
          * Set the watched UIDs for this request. This will be reset and wiped out unless
          * the calling app holds the CHANGE_NETWORK_STATE permission.
          *
-         * @param uids The watched UIDs as a set of UidRanges, or null for everything.
+         * @param uids The watched UIDs as a set of {@code Range<Integer>}, or null for everything.
          * @return The builder to facilitate chaining.
          * @hide
          */
-        public Builder setUids(Set<UidRange> uids) {
+        @NonNull
+        @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
+        @SuppressLint("MissingGetterMatchingBuilder")
+        public Builder setUids(@Nullable Set<Range<Integer>> uids) {
             mNetworkCapabilities.setUids(uids);
             return this;
         }
diff --git a/framework/src/android/net/NetworkScore.java b/framework/src/android/net/NetworkScore.java
new file mode 100644
index 0000000..e640737
--- /dev/null
+++ b/framework/src/android/net/NetworkScore.java
@@ -0,0 +1,118 @@
+/*
+ * 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 android.annotation.NonNull;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+/**
+ * Object representing the quality of a network as perceived by the user.
+ *
+ * A NetworkScore object represents the characteristics of a network that affects how good the
+ * network is considered for a particular use.
+ * @hide
+ */
+// TODO : @SystemApi when the implementation is complete
+public final class NetworkScore implements Parcelable {
+    // This will be removed soon. Do *NOT* depend on it for any new code that is not part of
+    // a migration.
+    private final int mLegacyInt;
+
+    // Agent-managed policies
+    // TODO : add them here, starting from 1
+
+    // Bitmask of all the policies applied to this score.
+    private final long mPolicies;
+
+    /** @hide */
+    NetworkScore(final int legacyInt, final long policies) {
+        mLegacyInt = legacyInt;
+        mPolicies = policies;
+    }
+
+    private NetworkScore(@NonNull final Parcel in) {
+        mLegacyInt = in.readInt();
+        mPolicies = in.readLong();
+    }
+
+    public int getLegacyInt() {
+        return mLegacyInt;
+    }
+
+    @Override
+    public String toString() {
+        return "Score(" + mLegacyInt + ")";
+    }
+
+    @Override
+    public void writeToParcel(@NonNull final Parcel dest, final int flags) {
+        dest.writeInt(mLegacyInt);
+        dest.writeLong(mPolicies);
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @NonNull public static final Creator<NetworkScore> CREATOR = new Creator<>() {
+        @Override
+        @NonNull
+        public NetworkScore createFromParcel(@NonNull final Parcel in) {
+            return new NetworkScore(in);
+        }
+
+        @Override
+        @NonNull
+        public NetworkScore[] newArray(int size) {
+            return new NetworkScore[size];
+        }
+    };
+
+    /**
+     * A builder for NetworkScore.
+     */
+    public static final class Builder {
+        private static final long POLICY_NONE = 0L;
+        private static final int INVALID_LEGACY_INT = Integer.MIN_VALUE;
+        private int mLegacyInt = INVALID_LEGACY_INT;
+
+        /**
+         * Sets the legacy int for this score.
+         *
+         * Do not rely on this. It will be gone by the time S is released.
+         *
+         * @param score the legacy int
+         * @return this
+         */
+        @NonNull
+        public Builder setLegacyInt(final int score) {
+            mLegacyInt = score;
+            return this;
+        }
+
+        /**
+         * Builds this NetworkScore.
+         * @return The built NetworkScore object.
+         */
+        @NonNull
+        public NetworkScore build() {
+            return new NetworkScore(mLegacyInt, POLICY_NONE);
+        }
+    }
+}
diff --git a/framework/src/android/net/StaticIpConfiguration.java b/framework/src/android/net/StaticIpConfiguration.java
index ce54597..7904f7a 100644
--- a/framework/src/android/net/StaticIpConfiguration.java
+++ b/framework/src/android/net/StaticIpConfiguration.java
@@ -24,7 +24,6 @@
 import android.os.Parcel;
 import android.os.Parcelable;
 
-import com.android.internal.util.Preconditions;
 import com.android.net.module.util.InetAddressUtils;
 
 import java.net.InetAddress;
@@ -153,7 +152,7 @@
          * @return The {@link Builder} for chaining.
          */
         public @NonNull Builder setDnsServers(@NonNull Iterable<InetAddress> dnsServers) {
-            Preconditions.checkNotNull(dnsServers);
+            Objects.requireNonNull(dnsServers);
             mDnsServers = dnsServers;
             return this;
         }
diff --git a/framework/src/android/net/TestNetworkManager.java b/framework/src/android/net/TestNetworkManager.java
index a174a7b..a7a6235 100644
--- a/framework/src/android/net/TestNetworkManager.java
+++ b/framework/src/android/net/TestNetworkManager.java
@@ -21,10 +21,9 @@
 import android.os.IBinder;
 import android.os.RemoteException;
 
-import com.android.internal.util.Preconditions;
-
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.Objects;
 
 /**
  * Class that allows creation and management of per-app, test-only networks
@@ -50,7 +49,7 @@
 
     /** @hide */
     public TestNetworkManager(@NonNull ITestNetworkManager service) {
-        mService = Preconditions.checkNotNull(service, "missing ITestNetworkManager");
+        mService = Objects.requireNonNull(service, "missing ITestNetworkManager");
     }
 
     /**
@@ -93,7 +92,7 @@
      */
     public void setupTestNetwork(
             @NonNull LinkProperties lp, boolean isMetered, @NonNull IBinder binder) {
-        Preconditions.checkNotNull(lp, "Invalid LinkProperties");
+        Objects.requireNonNull(lp, "Invalid LinkProperties");
         setupTestNetwork(lp.getInterfaceName(), lp, isMetered, new int[0], binder);
     }
 
diff --git a/framework/src/android/net/TestNetworkSpecifier.java b/framework/src/android/net/TestNetworkSpecifier.java
index b7470a5..117457d 100644
--- a/framework/src/android/net/TestNetworkSpecifier.java
+++ b/framework/src/android/net/TestNetworkSpecifier.java
@@ -23,8 +23,6 @@
 import android.os.Parcelable;
 import android.text.TextUtils;
 
-import com.android.internal.util.Preconditions;
-
 import java.util.Objects;
 
 /**
@@ -43,7 +41,9 @@
     private final String mInterfaceName;
 
     public TestNetworkSpecifier(@NonNull String interfaceName) {
-        Preconditions.checkStringNotEmpty(interfaceName);
+        if (TextUtils.isEmpty(interfaceName)) {
+            throw new IllegalArgumentException("Empty interfaceName");
+        }
         mInterfaceName = interfaceName;
     }
 
diff --git a/framework/src/android/net/UidRange.java b/framework/src/android/net/UidRange.java
index 26518d3..bc67c74 100644
--- a/framework/src/android/net/UidRange.java
+++ b/framework/src/android/net/UidRange.java
@@ -20,8 +20,11 @@
 import android.os.Parcel;
 import android.os.Parcelable;
 import android.os.UserHandle;
+import android.util.ArraySet;
+import android.util.Range;
 
 import java.util.Collection;
+import java.util.Set;
 
 /**
  * An inclusive range of UIDs.
@@ -149,4 +152,32 @@
         }
         return false;
     }
+
+    /**
+     *  Convert a set of {@code Range<Integer>} to a set of {@link UidRange}.
+     */
+    @Nullable
+    public static ArraySet<UidRange> fromIntRanges(@Nullable Set<Range<Integer>> ranges) {
+        if (null == ranges) return null;
+
+        final ArraySet<UidRange> uids = new ArraySet<>();
+        for (Range<Integer> range : ranges) {
+            uids.add(new UidRange(range.getLower(), range.getUpper()));
+        }
+        return uids;
+    }
+
+    /**
+     *  Convert a set of {@link UidRange} to a set of {@code Range<Integer>}.
+     */
+    @Nullable
+    public static ArraySet<Range<Integer>> toIntRanges(@Nullable Set<UidRange> ranges) {
+        if (null == ranges) return null;
+
+        final ArraySet<Range<Integer>> uids = new ArraySet<>();
+        for (UidRange range : ranges) {
+            uids.add(new Range<Integer>(range.start, range.stop));
+        }
+        return uids;
+    }
 }