diff --git a/tests/common/java/android/net/ConnectivityDiagnosticsManagerTest.java b/tests/common/java/android/net/ConnectivityDiagnosticsManagerTest.java
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+++ b/tests/common/java/android/net/ConnectivityDiagnosticsManagerTest.java
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+/*
+ * 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 static android.net.ConnectivityDiagnosticsManager.ConnectivityDiagnosticsBinder;
+import static android.net.ConnectivityDiagnosticsManager.ConnectivityDiagnosticsCallback;
+import static android.net.ConnectivityDiagnosticsManager.ConnectivityReport;
+import static android.net.ConnectivityDiagnosticsManager.DataStallReport;
+
+import static com.android.testutils.ParcelUtils.assertParcelSane;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+
+import android.content.Context;
+import android.os.Build;
+import android.os.PersistableBundle;
+
+import androidx.test.InstrumentationRegistry;
+import androidx.test.filters.SdkSuppress;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+import org.mockito.Mock;
+
+import java.util.concurrent.Executor;
+
+@RunWith(JUnit4.class)
+@SdkSuppress(minSdkVersion = Build.VERSION_CODES.S, codeName = "S")
+public class ConnectivityDiagnosticsManagerTest {
+    private static final int NET_ID = 1;
+    private static final int DETECTION_METHOD = 2;
+    private static final long TIMESTAMP = 10L;
+    private static final String INTERFACE_NAME = "interface";
+    private static final String BUNDLE_KEY = "key";
+    private static final String BUNDLE_VALUE = "value";
+
+    private static final Executor INLINE_EXECUTOR = x -> x.run();
+
+    @Mock private IConnectivityManager mService;
+    @Mock private ConnectivityDiagnosticsCallback mCb;
+
+    private Context mContext;
+    private ConnectivityDiagnosticsBinder mBinder;
+    private ConnectivityDiagnosticsManager mManager;
+
+    private String mPackageName;
+
+    @Before
+    public void setUp() {
+        mContext = InstrumentationRegistry.getContext();
+
+        mService = mock(IConnectivityManager.class);
+        mCb = mock(ConnectivityDiagnosticsCallback.class);
+
+        mBinder = new ConnectivityDiagnosticsBinder(mCb, INLINE_EXECUTOR);
+        mManager = new ConnectivityDiagnosticsManager(mContext, mService);
+
+        mPackageName = mContext.getOpPackageName();
+    }
+
+    @After
+    public void tearDown() {
+        // clear ConnectivityDiagnosticsManager callbacks map
+        ConnectivityDiagnosticsManager.sCallbacks.clear();
+    }
+
+    private ConnectivityReport createSampleConnectivityReport() {
+        final LinkProperties linkProperties = new LinkProperties();
+        linkProperties.setInterfaceName(INTERFACE_NAME);
+
+        final NetworkCapabilities networkCapabilities = new NetworkCapabilities();
+        networkCapabilities.addCapability(NetworkCapabilities.NET_CAPABILITY_IMS);
+
+        final PersistableBundle bundle = new PersistableBundle();
+        bundle.putString(BUNDLE_KEY, BUNDLE_VALUE);
+
+        return new ConnectivityReport(
+                new Network(NET_ID), TIMESTAMP, linkProperties, networkCapabilities, bundle);
+    }
+
+    private ConnectivityReport createDefaultConnectivityReport() {
+        return new ConnectivityReport(
+                new Network(0),
+                0L,
+                new LinkProperties(),
+                new NetworkCapabilities(),
+                PersistableBundle.EMPTY);
+    }
+
+    @Test
+    public void testPersistableBundleEquals() {
+        assertFalse(
+                ConnectivityDiagnosticsManager.persistableBundleEquals(
+                        null, PersistableBundle.EMPTY));
+        assertFalse(
+                ConnectivityDiagnosticsManager.persistableBundleEquals(
+                        PersistableBundle.EMPTY, null));
+        assertTrue(
+                ConnectivityDiagnosticsManager.persistableBundleEquals(
+                        PersistableBundle.EMPTY, PersistableBundle.EMPTY));
+
+        final PersistableBundle a = new PersistableBundle();
+        a.putString(BUNDLE_KEY, BUNDLE_VALUE);
+
+        final PersistableBundle b = new PersistableBundle();
+        b.putString(BUNDLE_KEY, BUNDLE_VALUE);
+
+        final PersistableBundle c = new PersistableBundle();
+        c.putString(BUNDLE_KEY, null);
+
+        assertFalse(
+                ConnectivityDiagnosticsManager.persistableBundleEquals(PersistableBundle.EMPTY, a));
+        assertFalse(
+                ConnectivityDiagnosticsManager.persistableBundleEquals(a, PersistableBundle.EMPTY));
+
+        assertTrue(ConnectivityDiagnosticsManager.persistableBundleEquals(a, b));
+        assertTrue(ConnectivityDiagnosticsManager.persistableBundleEquals(b, a));
+
+        assertFalse(ConnectivityDiagnosticsManager.persistableBundleEquals(a, c));
+        assertFalse(ConnectivityDiagnosticsManager.persistableBundleEquals(c, a));
+    }
+
+    @Test
+    public void testConnectivityReportEquals() {
+        final ConnectivityReport defaultReport = createDefaultConnectivityReport();
+        final ConnectivityReport sampleReport = createSampleConnectivityReport();
+        assertEquals(sampleReport, createSampleConnectivityReport());
+        assertEquals(defaultReport, createDefaultConnectivityReport());
+
+        final LinkProperties linkProperties = sampleReport.getLinkProperties();
+        final NetworkCapabilities networkCapabilities = sampleReport.getNetworkCapabilities();
+        final PersistableBundle bundle = sampleReport.getAdditionalInfo();
+
+        assertNotEquals(
+                createDefaultConnectivityReport(),
+                new ConnectivityReport(
+                        new Network(NET_ID),
+                        0L,
+                        new LinkProperties(),
+                        new NetworkCapabilities(),
+                        PersistableBundle.EMPTY));
+        assertNotEquals(
+                createDefaultConnectivityReport(),
+                new ConnectivityReport(
+                        new Network(0),
+                        TIMESTAMP,
+                        new LinkProperties(),
+                        new NetworkCapabilities(),
+                        PersistableBundle.EMPTY));
+        assertNotEquals(
+                createDefaultConnectivityReport(),
+                new ConnectivityReport(
+                        new Network(0),
+                        0L,
+                        linkProperties,
+                        new NetworkCapabilities(),
+                        PersistableBundle.EMPTY));
+        assertNotEquals(
+                createDefaultConnectivityReport(),
+                new ConnectivityReport(
+                        new Network(0),
+                        TIMESTAMP,
+                        new LinkProperties(),
+                        networkCapabilities,
+                        PersistableBundle.EMPTY));
+        assertNotEquals(
+                createDefaultConnectivityReport(),
+                new ConnectivityReport(
+                        new Network(0),
+                        TIMESTAMP,
+                        new LinkProperties(),
+                        new NetworkCapabilities(),
+                        bundle));
+    }
+
+    @Test
+    public void testConnectivityReportParcelUnparcel() {
+        assertParcelSane(createSampleConnectivityReport(), 5);
+    }
+
+    private DataStallReport createSampleDataStallReport() {
+        final LinkProperties linkProperties = new LinkProperties();
+        linkProperties.setInterfaceName(INTERFACE_NAME);
+
+        final PersistableBundle bundle = new PersistableBundle();
+        bundle.putString(BUNDLE_KEY, BUNDLE_VALUE);
+
+        final NetworkCapabilities networkCapabilities = new NetworkCapabilities();
+        networkCapabilities.addCapability(NetworkCapabilities.NET_CAPABILITY_IMS);
+
+        return new DataStallReport(
+                new Network(NET_ID),
+                TIMESTAMP,
+                DETECTION_METHOD,
+                linkProperties,
+                networkCapabilities,
+                bundle);
+    }
+
+    private DataStallReport createDefaultDataStallReport() {
+        return new DataStallReport(
+                new Network(0),
+                0L,
+                0,
+                new LinkProperties(),
+                new NetworkCapabilities(),
+                PersistableBundle.EMPTY);
+    }
+
+    @Test
+    public void testDataStallReportEquals() {
+        final DataStallReport defaultReport = createDefaultDataStallReport();
+        final DataStallReport sampleReport = createSampleDataStallReport();
+        assertEquals(sampleReport, createSampleDataStallReport());
+        assertEquals(defaultReport, createDefaultDataStallReport());
+
+        final LinkProperties linkProperties = sampleReport.getLinkProperties();
+        final NetworkCapabilities networkCapabilities = sampleReport.getNetworkCapabilities();
+        final PersistableBundle bundle = sampleReport.getStallDetails();
+
+        assertNotEquals(
+                defaultReport,
+                new DataStallReport(
+                        new Network(NET_ID),
+                        0L,
+                        0,
+                        new LinkProperties(),
+                        new NetworkCapabilities(),
+                        PersistableBundle.EMPTY));
+        assertNotEquals(
+                defaultReport,
+                new DataStallReport(
+                        new Network(0),
+                        TIMESTAMP,
+                        0,
+                        new LinkProperties(),
+                        new NetworkCapabilities(),
+                        PersistableBundle.EMPTY));
+        assertNotEquals(
+                defaultReport,
+                new DataStallReport(
+                        new Network(0),
+                        0L,
+                        DETECTION_METHOD,
+                        new LinkProperties(),
+                        new NetworkCapabilities(),
+                        PersistableBundle.EMPTY));
+        assertNotEquals(
+                defaultReport,
+                new DataStallReport(
+                        new Network(0),
+                        0L,
+                        0,
+                        linkProperties,
+                        new NetworkCapabilities(),
+                        PersistableBundle.EMPTY));
+        assertNotEquals(
+                defaultReport,
+                new DataStallReport(
+                        new Network(0),
+                        0L,
+                        0,
+                        new LinkProperties(),
+                        networkCapabilities,
+                        PersistableBundle.EMPTY));
+        assertNotEquals(
+                defaultReport,
+                new DataStallReport(
+                        new Network(0),
+                        0L,
+                        0,
+                        new LinkProperties(),
+                        new NetworkCapabilities(),
+                        bundle));
+    }
+
+    @Test
+    public void testDataStallReportParcelUnparcel() {
+        assertParcelSane(createSampleDataStallReport(), 6);
+    }
+
+    @Test
+    public void testConnectivityDiagnosticsCallbackOnConnectivityReportAvailable() {
+        mBinder.onConnectivityReportAvailable(createSampleConnectivityReport());
+
+        // The callback will be invoked synchronously by inline executor. Immediately check the
+        // latch without waiting.
+        verify(mCb).onConnectivityReportAvailable(eq(createSampleConnectivityReport()));
+    }
+
+    @Test
+    public void testConnectivityDiagnosticsCallbackOnDataStallSuspected() {
+        mBinder.onDataStallSuspected(createSampleDataStallReport());
+
+        // The callback will be invoked synchronously by inline executor. Immediately check the
+        // latch without waiting.
+        verify(mCb).onDataStallSuspected(eq(createSampleDataStallReport()));
+    }
+
+    @Test
+    public void testConnectivityDiagnosticsCallbackOnNetworkConnectivityReported() {
+        final Network n = new Network(NET_ID);
+        final boolean connectivity = true;
+
+        mBinder.onNetworkConnectivityReported(n, connectivity);
+
+        // The callback will be invoked synchronously by inline executor. Immediately check the
+        // latch without waiting.
+        verify(mCb).onNetworkConnectivityReported(eq(n), eq(connectivity));
+    }
+
+    @Test
+    public void testRegisterConnectivityDiagnosticsCallback() throws Exception {
+        final NetworkRequest request = new NetworkRequest.Builder().build();
+
+        mManager.registerConnectivityDiagnosticsCallback(request, INLINE_EXECUTOR, mCb);
+
+        verify(mService).registerConnectivityDiagnosticsCallback(
+                any(ConnectivityDiagnosticsBinder.class), eq(request), eq(mPackageName));
+        assertTrue(ConnectivityDiagnosticsManager.sCallbacks.containsKey(mCb));
+    }
+
+    @Test
+    public void testRegisterDuplicateConnectivityDiagnosticsCallback() throws Exception {
+        final NetworkRequest request = new NetworkRequest.Builder().build();
+
+        mManager.registerConnectivityDiagnosticsCallback(request, INLINE_EXECUTOR, mCb);
+
+        try {
+            mManager.registerConnectivityDiagnosticsCallback(request, INLINE_EXECUTOR, mCb);
+            fail("Duplicate callback registration should fail");
+        } catch (IllegalArgumentException expected) {
+        }
+    }
+
+    @Test
+    public void testUnregisterConnectivityDiagnosticsCallback() throws Exception {
+        final NetworkRequest request = new NetworkRequest.Builder().build();
+        mManager.registerConnectivityDiagnosticsCallback(request, INLINE_EXECUTOR, mCb);
+
+        mManager.unregisterConnectivityDiagnosticsCallback(mCb);
+
+        verify(mService).unregisterConnectivityDiagnosticsCallback(
+                any(ConnectivityDiagnosticsBinder.class));
+        assertFalse(ConnectivityDiagnosticsManager.sCallbacks.containsKey(mCb));
+
+        // verify that re-registering is successful
+        mManager.registerConnectivityDiagnosticsCallback(request, INLINE_EXECUTOR, mCb);
+        verify(mService, times(2)).registerConnectivityDiagnosticsCallback(
+                any(ConnectivityDiagnosticsBinder.class), eq(request), eq(mPackageName));
+        assertTrue(ConnectivityDiagnosticsManager.sCallbacks.containsKey(mCb));
+    }
+
+    @Test
+    public void testUnregisterUnknownConnectivityDiagnosticsCallback() throws Exception {
+        mManager.unregisterConnectivityDiagnosticsCallback(mCb);
+
+        verifyNoMoreInteractions(mService);
+    }
+}