Manage scan requests in MediaRouter2Manager am: cbca646e97 (783ed3f0) · Commits · e / os / android_frameworks_base

media/java/android/media/MediaRouter2.java

+8 −2

Original line number	Diff line number	Diff line
		@@ -48,6 +48,7 @@ import java.util.Objects;
		import java.util.Set;
		import java.util.concurrent.CopyOnWriteArrayList;
		import java.util.concurrent.Executor;
		import java.util.concurrent.atomic.AtomicBoolean;
		import java.util.concurrent.atomic.AtomicInteger;
		import java.util.stream.Collectors;

		@@ -118,6 +119,7 @@ public final class MediaRouter2 {
		private final Map<String, RoutingController> mNonSystemRoutingControllers = new ArrayMap<>();

		private final AtomicInteger mNextRequestId = new AtomicInteger(1);
		private final AtomicBoolean mIsScanning = new AtomicBoolean(/* initialValue= */ false);

		final Handler mHandler;

		@@ -234,7 +236,9 @@ public final class MediaRouter2 {
		@RequiresPermission(Manifest.permission.MEDIA_CONTENT_CONTROL)
		public void startScan() {
		if (isSystemRouter()) {
		sManager.startScan();
		if (!mIsScanning.getAndSet(true)) {
		sManager.registerScanRequest();
		}
		}
		}

		@@ -260,7 +264,9 @@ public final class MediaRouter2 {
		@RequiresPermission(Manifest.permission.MEDIA_CONTENT_CONTROL)
		public void stopScan() {
		if (isSystemRouter()) {
		sManager.stopScan();
		if (mIsScanning.getAndSet(false)) {
		sManager.unregisterScanRequest();
		}
		}
		}

media/java/android/media/MediaRouter2Manager.java

+28 −26

Original line number	Diff line number	Diff line
		@@ -82,6 +82,7 @@ public final class MediaRouter2Manager {
		@GuardedBy("sLock")
		private Client mClient;
		private final IMediaRouterService mMediaRouterService;
		private final AtomicInteger mScanRequestCount = new AtomicInteger(/* initialValue= */ 0);
		final Handler mHandler;
		final CopyOnWriteArrayList<CallbackRecord> mCallbackRecords = new CopyOnWriteArrayList<>();

		@@ -155,20 +156,17 @@ public final class MediaRouter2Manager {
		}

		/**
		* Starts scanning remote routes.
		* <p>
		* Route discovery can happen even when the {@link #startScan()} is not called.
		* This is because the scanning could be started before by other apps.
		* Therefore, calling this method after calling {@link #stopScan()} does not necessarily mean
		* that the routes found before are removed and added again.
		* <p>
		* Use {@link Callback} to get the route related events.
		* <p>
		* @see #stopScan()
		* Registers a request to scan for remote routes.
		*
		* <p>Increases the count of active scanning requests. When the count transitions from zero to
		* one, sends a request to the system server to start scanning.
		*
		* <p>Clients must {@link #unregisterScanRequest() unregister their scan requests} when scanning
		* is no longer needed, to avoid unnecessary resource usage.
		*/
		public void startScan() {
		public void registerScanRequest() {
		if (mScanRequestCount.getAndIncrement() == 0) {
		Client client = getOrCreateClient();
		if (client != null) {
		try {
		mMediaRouterService.startScan(client);
		} catch (RemoteException ex) {
		@@ -178,21 +176,25 @@ public final class MediaRouter2Manager {
		}

		/**
		* Stops scanning remote routes to reduce resource consumption.
		* <p>
		* Route discovery can be continued even after this method is called.
		* This is because the scanning is only turned off when all the apps stop scanning.
		* Therefore, calling this method does not necessarily mean the routes are removed.
		* Also, for the same reason it does not mean that {@link Callback#onRoutesAdded(List)}
		* is not called afterwards.
		* <p>
		* Use {@link Callback} to get the route related events.
		* Unregisters a scan request made by {@link #registerScanRequest()}.
		*
		* <p>Decreases the count of active scanning requests. When the count transitions from one to
		* zero, sends a request to the system server to stop scanning.
		*
		* @see #startScan()
		* @throws IllegalStateException If called while there are no active scan requests.
		*/
		public void stopScan() {
		public void unregisterScanRequest() {
		if (mScanRequestCount.updateAndGet(
		count -> {
		if (count == 0) {
		throw new IllegalStateException(
		"No active scan requests to unregister.");
		} else {
		return --count;
		}
		})
		== 0) {
		Client client = getOrCreateClient();
		if (client != null) {
		try {
		mMediaRouterService.stopScan(client);
		} catch (RemoteException ex) {

media/tests/MediaRouter/src/com/android/mediaroutertest/MediaRouter2ManagerTest.java

+10 −2

Original line number	Diff line number	Diff line
		@@ -39,6 +39,7 @@ import static org.junit.Assert.assertEquals;
		import static org.junit.Assert.assertFalse;
		import static org.junit.Assert.assertNotNull;
		import static org.junit.Assert.assertNull;
		import static org.junit.Assert.assertThrows;
		import static org.junit.Assert.assertTrue;

		import android.Manifest;
		@@ -121,7 +122,7 @@ public class MediaRouter2ManagerTest {
		MediaRouter2ManagerTestActivity.startActivity(mContext);

		mManager = MediaRouter2Manager.getInstance(mContext);
		mManager.startScan();
		mManager.registerScanRequest();
		mRouter2 = MediaRouter2.getInstance(mContext);

		// If we need to support thread pool executors, change this to thread pool executor.
		@@ -152,7 +153,7 @@ public class MediaRouter2ManagerTest {

		@After
		public void tearDown() {
		mManager.stopScan();
		mManager.unregisterScanRequest();

		// order matters (callbacks should be cleared at the last)
		releaseAllSessions();
		@@ -818,6 +819,13 @@ public class MediaRouter2ManagerTest {
		assertFalse(failureLatch.await(WAIT_TIME_MS, TimeUnit.MILLISECONDS));
		}

		@Test
		public void unregisterScanRequest_enforcesANonNegativeCount() {
		mManager.unregisterScanRequest(); // One request was made in the test setup.
		assertThrows(IllegalStateException.class, () -> mManager.unregisterScanRequest());
		mManager.registerScanRequest(); // So that the cleanup doesn't fail.
		}

		/**
		* Tests if getSelectableRoutes and getDeselectableRoutes filter routes based on
		* selected routes

packages/SettingsLib/src/com/android/settingslib/media/InfoMediaManager.java

+2 −2

Original line number	Diff line number	Diff line
		@@ -96,14 +96,14 @@ public class InfoMediaManager extends MediaManager {
		public void startScan() {
		mMediaDevices.clear();
		mRouterManager.registerCallback(mExecutor, mMediaRouterCallback);
		mRouterManager.startScan();
		mRouterManager.registerScanRequest();
		refreshDevices();
		}

		@Override
		public void stopScan() {
		mRouterManager.unregisterCallback(mMediaRouterCallback);
		mRouterManager.stopScan();
		mRouterManager.unregisterScanRequest();
		}

		/**