2 files changed, 171 insertions, 13 deletions
diff --git a/core/java/android/net/NetworkRequest.java b/core/java/android/net/NetworkRequest.java
index c7b30096db29..3be49d530c64 100644
--- a/core/java/android/net/NetworkRequest.java
+++ b/core/java/android/net/NetworkRequest.java
@@ -300,22 +300,34 @@ public class NetworkRequest implements Parcelable {
          * this without a single transport set will generate an exception, as will
          * subsequently adding or removing transports after this is set.
          * </p>
-         * The interpretation of this {@code String} is bearer specific and bearers that use
-         * it should document their particulars.  For example, Bluetooth may use some sort of
-         * device id while WiFi could used ssid and/or bssid.  Cellular may use carrier spn.
+         * If the {@code networkSpecifier} is provided, it shall be interpreted as follows:
+         * <ul>
+         * <li>If the specifier can be parsed as an integer, it will be treated as a
+         * {@link android.net TelephonyNetworkSpecifier}, and the provided integer will be
+         * interpreted as a SubscriptionId.
+         * <li>If the value is an ethernet interface name, it will be treated as such.
+         * <li>For all other cases, the behavior is undefined.
+         * </ul>
          *
-         * @param networkSpecifier An {@code String} of opaque format used to specify the bearer
-         *                         specific network specifier where the bearer has a choice of
-         *                         networks.
+         * @param networkSpecifier A {@code String} of either a SubscriptionId in cellular
+         *                         network request or an ethernet interface name in ethernet
+         *                         network request.
+         *
+         * @deprecated Use {@link #setNetworkSpecifier(NetworkSpecifier)} instead.
          */
+        @Deprecated
         public Builder setNetworkSpecifier(String networkSpecifier) {
-            /*
-             * A StringNetworkSpecifier does not accept null or empty ("") strings. When network
-             * specifiers were strings a null string and an empty string were considered equivalent.
-             * Hence no meaning is attached to a null or empty ("") string.
-             */
-            return setNetworkSpecifier(TextUtils.isEmpty(networkSpecifier) ? null
-                    : new StringNetworkSpecifier(networkSpecifier));
+            try {
+                int subId = Integer.parseInt(networkSpecifier);
+                return setNetworkSpecifier(new TelephonyNetworkSpecifier.Builder()
+                        .setSubscriptionId(subId).build());
+            } catch (NumberFormatException nfe) {
+                // A StringNetworkSpecifier does not accept null or empty ("") strings. When network
+                // specifiers were strings a null string and an empty string were considered
+                // equivalent. Hence no meaning is attached to a null or empty ("") string.
+                return setNetworkSpecifier(TextUtils.isEmpty(networkSpecifier) ? null
+                        : new StringNetworkSpecifier(networkSpecifier));
+            }
         }
 
         /**
diff --git a/core/java/android/net/TelephonyNetworkSpecifier.java b/core/java/android/net/TelephonyNetworkSpecifier.java
new file mode 100644
index 000000000000..726f77059707
--- /dev/null
+++ b/core/java/android/net/TelephonyNetworkSpecifier.java
@@ -0,0 +1,146 @@
+/*
+ * 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;
+
+import android.annotation.NonNull;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+/**
+ * NetworkSpecifier object for cellular network request. Apps should use the
+ * {@link TelephonyNetworkSpecifier.Builder} class to create an instance.
+ */
+public final class TelephonyNetworkSpecifier extends NetworkSpecifier implements Parcelable {
+
+    private final int mSubId;
+
+    /**
+     * Return the subscription Id of current TelephonyNetworkSpecifier object.
+     *
+     * @return The subscription id.
+     */
+    public int getSubscriptionId() {
+        return mSubId;
+    }
+
+    /**
+     * @hide
+     */
+    public TelephonyNetworkSpecifier(int subId) {
+        this.mSubId = subId;
+    }
+
+    public static final @NonNull Creator<TelephonyNetworkSpecifier> CREATOR =
+            new Creator<TelephonyNetworkSpecifier>() {
+                @Override
+                public TelephonyNetworkSpecifier createFromParcel(Parcel in) {
+                    int subId = in.readInt();
+                    return new TelephonyNetworkSpecifier(subId);
+                }
+
+                @Override
+                public TelephonyNetworkSpecifier[] newArray(int size) {
+                    return new TelephonyNetworkSpecifier[size];
+                }
+            };
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        dest.writeInt(mSubId);
+    }
+
+    @Override
+    public int hashCode() {
+        return mSubId;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (!(obj instanceof TelephonyNetworkSpecifier)) {
+            return false;
+        }
+
+        TelephonyNetworkSpecifier lhs = (TelephonyNetworkSpecifier) obj;
+        return mSubId == lhs.mSubId;
+    }
+
+    @Override
+    public String toString() {
+        return new StringBuilder()
+                .append("TelephonyNetworkSpecifier [")
+                .append("mSubId = ").append(mSubId)
+                .append("]")
+                .toString();
+    }
+
+    /** @hide */
+    @Override
+    public boolean satisfiedBy(NetworkSpecifier other) {
+        // Any generic requests should be satisfied by a specific telephony network.
+        // For simplicity, we treat null same as MatchAllNetworkSpecifier
+        return equals(other) || other == null || other instanceof MatchAllNetworkSpecifier;
+    }
+
+
+    /**
+     * Builder to create {@link TelephonyNetworkSpecifier} object.
+     */
+    public static final class Builder {
+        // Integer.MIN_VALUE which is not a valid subId, services as the sentinel to check if
+        // subId was set
+        private static final int SENTINEL_SUB_ID = Integer.MIN_VALUE;
+
+        private int mSubId;
+
+        public Builder() {
+            mSubId = SENTINEL_SUB_ID;
+        }
+
+        /**
+         * Set the subscription id.
+         *
+         * @param subId The subscription Id.
+         * @return Instance of {@link Builder} to enable the chaining of the builder method.
+         */
+        public @NonNull Builder setSubscriptionId(int subId) {
+            mSubId = subId;
+            return this;
+        }
+
+        /**
+         * Create a NetworkSpecifier for the cellular network request.
+         *
+         * @return TelephonyNetworkSpecifier object.
+         * @throws IllegalArgumentException when subscription Id is not provided through
+         *         {@link #setSubscriptionId(int)}.
+         */
+        public @NonNull TelephonyNetworkSpecifier build() {
+            if (mSubId == SENTINEL_SUB_ID) {
+                throw new IllegalArgumentException("Subscription Id is not provided.");
+            }
+            return new TelephonyNetworkSpecifier(mSubId);
+        }
+    }
+}