Move offload events to their own listener

Move offload events from Player.EventListener to
ExoPlayer.AudioOffloadListener.

PiperOrigin-RevId: 362472462

library/common/src/main/java/com/google/android/exoplayer2/Player.java

@@ -612,24 +612,6 @@ public interface Player {
     @Deprecated
     default void onSeekProcessed() {}
 
-    /**
-     * Called when the player has started or stopped offload scheduling.
-     *
-     * <p>If using ExoPlayer, this is done by calling {@code
-     * ExoPlayer#experimentalSetOffloadSchedulingEnabled(boolean)}.
-     *
-     * <p>This method is experimental, and will be renamed or removed in a future release.
-     */
-    // TODO(b/172315872) Move this method in a new ExoPlayer.EventListener.
-    default void onExperimentalOffloadSchedulingEnabledChanged(boolean offloadSchedulingEnabled) {}
-
-    /**
-     * Called when the player has started or finished sleeping for offload.
-     *
-     * <p>This method is experimental, and will be renamed or removed in a future release.
-     */
-    default void onExperimentalSleepingForOffloadChanged(boolean sleepingForOffload) {}
-
     /**
      * Called when one or more player states changed.
      *

library/core/src/main/java/com/google/android/exoplayer2/ExoPlayer.java

@@ -140,6 +140,28 @@ public interface ExoPlayer extends Player {
    */
   long DEFAULT_RELEASE_TIMEOUT_MS = 500;
 
+  /**
+   * A listener for audio offload events.
+   *
+   * <p>This class is experimental, and might be renamed, moved or removed in a future release.
+   */
+  interface AudioOffloadListener {
+    /**
+     * Called when the player has started or stopped offload scheduling using {@link
+     * ExoPlayer#experimentalSetOffloadSchedulingEnabled(boolean)}.
+     *
+     * <p>This method is experimental, and will be renamed or removed in a future release.
+     */
+    default void onExperimentalOffloadSchedulingEnabledChanged(boolean offloadSchedulingEnabled) {}
+
+    /**
+     * Called when the player has started or finished sleeping for offload.
+     *
+     * <p>This method is experimental, and will be renamed or removed in a future release.
+     */
+    default void onExperimentalSleepingForOffloadChanged(boolean sleepingForOffload) {}
+  }
+
   /**
    * A builder for {@link ExoPlayer} instances.
    *
@@ -450,6 +472,20 @@ public interface ExoPlayer extends Player {
     }
   }
 
+  /**
+   * Adds a listener to receive audio offload events.
+   *
+   * @param listener The listener to register.
+   */
+  void addAudioOffloadListener(AudioOffloadListener listener);
+
+  /**
+   * Removes a listener of audio offload events.
+   *
+   * @param listener The listener to unregister.
+   */
+  void removeAudioOffloadListener(AudioOffloadListener listener);
+
   /** Returns the number of renderers. */
   int getRendererCount();
 
@@ -665,7 +701,7 @@ public interface ExoPlayer extends Player {
    * <p>While offload scheduling is enabled, player events may be delivered severely delayed and
    * apps should not interact with the player. When returning to the foreground, disable offload
    * scheduling and wait for {@link
-   * Player.EventListener#onExperimentalOffloadSchedulingEnabledChanged(boolean)} to be called with
+   * AudioOffloadListener#onExperimentalOffloadSchedulingEnabledChanged(boolean)} to be called with
    * {@code offloadSchedulingEnabled = false} before interacting with the player.
    *
    * <p>This mode should save significant power when the phone is playing offload audio with the
@@ -697,7 +733,7 @@ public interface ExoPlayer extends Player {
    * Returns whether the player has paused its main loop to save power in offload scheduling mode.
    *
    * @see #experimentalSetOffloadSchedulingEnabled(boolean)
-   * @see EventListener#onExperimentalSleepingForOffloadChanged(boolean)
+   * @see AudioOffloadListener#onExperimentalSleepingForOffloadChanged(boolean)
    */
   boolean experimentalIsSleepingForOffload();
 }

library/core/src/main/java/com/google/android/exoplayer2/ExoPlayerImpl.java

@@ -49,6 +49,7 @@ import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.concurrent.CopyOnWriteArraySet;
 
 /**
  * An {@link ExoPlayer} implementation. Instances can be obtained from {@link ExoPlayer.Builder}.
@@ -72,6 +73,7 @@ import java.util.List;
   private final ExoPlayerImplInternal.PlaybackInfoUpdateListener playbackInfoUpdateListener;
   private final ExoPlayerImplInternal internalPlayer;
   private final ListenerSet<Player.EventListener> listeners;
+  private final CopyOnWriteArraySet<AudioOffloadListener> audioOffloadListeners;
   private final Timeline.Period period;
   private final List<MediaSourceHolderSnapshot> mediaSourceHolderSnapshots;
   private final boolean useLazyPreparation;
@@ -166,6 +168,7 @@ import java.util.List;
             applicationLooper,
             clock,
             (listener, flags) -> listener.onEvents(playerForListeners, new Events(flags)));
+    audioOffloadListeners = new CopyOnWriteArraySet<>();
     mediaSourceHolderSnapshots = new ArrayList<>();
     shuffleOrder = new ShuffleOrder.DefaultShuffleOrder(/* length= */ 0);
     emptyTrackSelectorResult =
@@ -284,6 +287,16 @@ import java.util.List;
     listeners.remove(listener);
   }
 
+  @Override
+  public void addAudioOffloadListener(AudioOffloadListener listener) {
+    audioOffloadListeners.add(listener);
+  }
+
+  @Override
+  public void removeAudioOffloadListener(AudioOffloadListener listener) {
+    audioOffloadListeners.remove(listener);
+  }
+
   @Override
   public boolean isCommandAvailable(@Command int command) {
     return availableCommands.contains(command);
@@ -1099,21 +1112,20 @@ import java.util.List;
     if (seekProcessed) {
       listeners.queueEvent(/* eventFlag= */ C.INDEX_UNSET, EventListener::onSeekProcessed);
     }
-    if (previousPlaybackInfo.offloadSchedulingEnabled != newPlaybackInfo.offloadSchedulingEnabled) {
-      listeners.queueEvent(
-          /* eventFlag= */ C.INDEX_UNSET,
-          listener ->
-              listener.onExperimentalOffloadSchedulingEnabledChanged(
-                  newPlaybackInfo.offloadSchedulingEnabled));
-    }
-    if (previousPlaybackInfo.sleepingForOffload != newPlaybackInfo.sleepingForOffload) {
-      listeners.queueEvent(
-          /* eventFlag= */ C.INDEX_UNSET,
-          listener ->
-              listener.onExperimentalSleepingForOffloadChanged(newPlaybackInfo.sleepingForOffload));
-    }
     updateAvailableCommands();
     listeners.flushEvents();
+
+    if (previousPlaybackInfo.offloadSchedulingEnabled != newPlaybackInfo.offloadSchedulingEnabled) {
+      for (AudioOffloadListener listener : audioOffloadListeners) {
+        listener.onExperimentalOffloadSchedulingEnabledChanged(
+            newPlaybackInfo.offloadSchedulingEnabled);
+      }
+    }
+    if (previousPlaybackInfo.sleepingForOffload != newPlaybackInfo.sleepingForOffload) {
+      for (AudioOffloadListener listener : audioOffloadListeners) {
+        listener.onExperimentalSleepingForOffloadChanged(newPlaybackInfo.sleepingForOffload);
+      }
+    }
   }
 
   private Pair<Boolean, Integer> evaluateMediaItemTransitionReason(

library/core/src/main/java/com/google/android/exoplayer2/SimpleExoPlayer.java

@@ -685,6 +685,7 @@ public class SimpleExoPlayer extends BasePlayer
             builder.looper,
             /* wrappingPlayer= */ this);
     player.addListener(componentListener);
+    player.addAudioOffloadListener(componentListener);
 
     audioBecomingNoisyManager =
         new AudioBecomingNoisyManager(builder.context, eventHandler, componentListener);
@@ -894,6 +895,18 @@ public class SimpleExoPlayer extends BasePlayer
     }
   }
 
+  @Override
+  public void addAudioOffloadListener(AudioOffloadListener listener) {
+    // Don't verify application thread. We allow calls to this method from any thread.
+    player.addAudioOffloadListener(listener);
+  }
+
+  @Override
+  public void removeAudioOffloadListener(AudioOffloadListener listener) {
+    // Don't verify application thread. We allow calls to this method from any thread.
+    player.removeAudioOffloadListener(listener);
+  }
+
   @Override
   public void addAudioListener(AudioListener listener) {
     // Don't verify application thread. We allow calls to this method from any thread.
@@ -1973,7 +1986,8 @@ public class SimpleExoPlayer extends BasePlayer
           AudioFocusManager.PlayerControl,
           AudioBecomingNoisyManager.EventListener,
           StreamVolumeManager.Listener,
-          Player.EventListener {
+          Player.EventListener,
+          AudioOffloadListener {
 
     // VideoRendererEventListener implementation
 
@@ -2241,6 +2255,8 @@ public class SimpleExoPlayer extends BasePlayer
       updateWakeAndWifiLock();
     }
 
+    // Player.AudioOffloadListener implementation.
+
     @Override
     public void onExperimentalSleepingForOffloadChanged(boolean sleepingForOffload) {
       updateWakeAndWifiLock();

robolectricutils/src/main/java/com/google/android/exoplayer2/robolectric/TestPlayerRunHelper.java

@@ -210,46 +210,48 @@ public class TestPlayerRunHelper {
 
   /**
    * Runs tasks of the main {@link Looper} until a {@link
-   * Player.EventListener#onExperimentalOffloadSchedulingEnabledChanged} callback occurred.
+   * ExoPlayer.AudioOffloadListener#onExperimentalOffloadSchedulingEnabledChanged} callback
+   * occurred.
    *
    * @param player The {@link Player}.
    * @return The new offloadSchedulingEnabled state.
    * @throws TimeoutException If the {@link RobolectricUtil#DEFAULT_TIMEOUT_MS default timeout} is
    *     exceeded.
    */
-  public static boolean runUntilReceiveOffloadSchedulingEnabledNewState(Player player)
+  public static boolean runUntilReceiveOffloadSchedulingEnabledNewState(ExoPlayer player)
       throws TimeoutException {
     verifyMainTestThread(player);
     AtomicReference<@NullableType Boolean> offloadSchedulingEnabledReceiver =
         new AtomicReference<>();
-    Player.EventListener listener =
+    ExoPlayer.AudioOffloadListener listener =
-        new Player.EventListener() {
+        new ExoPlayer.AudioOffloadListener() {
           @Override
           public void onExperimentalOffloadSchedulingEnabledChanged(
               boolean offloadSchedulingEnabled) {
             offloadSchedulingEnabledReceiver.set(offloadSchedulingEnabled);
           }
         };
-    player.addListener(listener);
+    player.addAudioOffloadListener(listener);
     runMainLooperUntil(() -> offloadSchedulingEnabledReceiver.get() != null);
     return Assertions.checkNotNull(offloadSchedulingEnabledReceiver.get());
   }
 
   /**
    * Runs tasks of the main {@link Looper} until a {@link
-   * Player.EventListener#onExperimentalSleepingForOffloadChanged(boolean)} callback occurred.
+   * ExoPlayer.AudioOffloadListener#onExperimentalSleepingForOffloadChanged(boolean)} callback
+   * occurred.
    *
    * @param player The {@link Player}.
    * @param expectedSleepForOffload The expected sleep of offload state.
    * @throws TimeoutException If the {@link RobolectricUtil#DEFAULT_TIMEOUT_MS default timeout} is
    *     exceeded.
    */
-  public static void runUntilSleepingForOffload(Player player, boolean expectedSleepForOffload)
+  public static void runUntilSleepingForOffload(ExoPlayer player, boolean expectedSleepForOffload)
       throws TimeoutException {
     verifyMainTestThread(player);
     AtomicBoolean receiverCallback = new AtomicBoolean(false);
-    Player.EventListener listener =
+    ExoPlayer.AudioOffloadListener listener =
-        new Player.EventListener() {
+        new ExoPlayer.AudioOffloadListener() {
           @Override
           public void onExperimentalSleepingForOffloadChanged(boolean sleepingForOffload) {
             if (sleepingForOffload == expectedSleepForOffload) {
@@ -257,7 +259,7 @@ public class TestPlayerRunHelper {
             }
           }
         };
-    player.addListener(listener);
+    player.addAudioOffloadListener(listener);
     runMainLooperUntil(
         () -> { // Make sure progress is being made, see [internal: b/170387438#comment2]
           assertThat(player.getPlayerError()).isNull();

testutils/src/main/java/com/google/android/exoplayer2/testutil/StubExoPlayer.java

@@ -91,6 +91,16 @@ public abstract class StubExoPlayer extends BasePlayer implements ExoPlayer {
     throw new UnsupportedOperationException();
   }
 
+  @Override
+  public void addAudioOffloadListener(AudioOffloadListener listener) {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public void removeAudioOffloadListener(AudioOffloadListener listener) {
+    throw new UnsupportedOperationException();
+  }
+
   @Override
   @State
   public int getPlaybackState() {