Add getter for the fields of NetworkStats.Entry

NetworkStats is going to be moved into mainline module and
there're some external callers have dependencies on it.
To replace those hidden APIs with formal APIs, NetworkStats
needs to expose some getter methods to eliminate the dependencies
on hidden API.

Bug: 210073043
Bug: 204830222
CTS-Coverage-Bug: 214881138
Test: FrameworksNetTests
Change-Id: I85bb6b27bd17bad16c9693d95b569d0ec5fbb785

framework-t/src/android/net/NetworkStats.java

@@ -383,6 +383,95 @@ public final class NetworkStats implements Parcelable {
             this.operations += another.operations;
         }
 
+        /**
+         * @return interface name of this entry.
+         * @hide
+         */
+        @Nullable public String getIface() {
+            return iface;
+        }
+
+        /**
+         * @return the uid of this entry.
+         */
+        public int getUid() {
+            return uid;
+        }
+
+        /**
+         * @return the set state of this entry. Should be one of the following
+         * values: {@link #SET_DEFAULT}, {@link #SET_FOREGROUND}.
+         */
+        @State public int getSet() {
+            return set;
+        }
+
+        /**
+         * @return the tag value of this entry.
+         */
+        public int getTag() {
+            return tag;
+        }
+
+        /**
+         * @return the metered state. Should be one of the following
+         * values: {link #METERED_YES}, {link #METERED_NO}.
+         */
+        @Meteredness public int getMetered() {
+            return metered;
+        }
+
+        /**
+         * @return the roaming state. Should be one of the following
+         * values: {link #ROAMING_YES}, {link #ROAMING_NO}.
+         */
+        @Roaming public int getRoaming() {
+            return roaming;
+        }
+
+        /**
+         * @return the default network state. Should be one of the following
+         * values: {link #DEFAULT_NETWORK_YES}, {link #DEFAULT_NETWORK_NO}.
+         */
+        @DefaultNetwork public int getDefaultNetwork() {
+            return defaultNetwork;
+        }
+
+        /**
+         * @return the number of received bytes.
+         */
+        public long getRxBytes() {
+            return rxBytes;
+        }
+
+        /**
+         * @return the number of received packets.
+         */
+        public long getRxPackets() {
+            return rxPackets;
+        }
+
+        /**
+         * @return the number of transmitted bytes.
+         */
+        public long getTxBytes() {
+            return txBytes;
+        }
+
+        /**
+         * @return the number of transmitted packets.
+         */
+        public long getTxPackets() {
+            return txPackets;
+        }
+
+        /**
+         * @return the count of network operations performed for this entry.
+         */
+        public long getOperations() {
+            return operations;
+        }
+
         @Override
         public String toString() {
             final StringBuilder builder = new StringBuilder();
@@ -593,7 +682,7 @@ public final class NetworkStats implements Parcelable {
      * @hide
      */
     @UnsupportedAppUsage
-    public Entry getValues(int i, Entry recycle) {
+    public Entry getValues(int i, @Nullable Entry recycle) {
         final Entry entry = recycle != null ? recycle : new Entry();
         entry.iface = iface[i];
         entry.uid = uid[i];