Deprecate Player.DefaultEventListener in favor of default no-ops in interface.

The DefaultEventListener was added for selective overrides. Now that Java 8
support is enabled, these selective listener overrides can be implemented
more easily and more flexible using default methods.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=201695490

RELEASENOTES.md

@@ -40,6 +40,8 @@
   `ExoPlayerFactory` ([#4278](https://github.com/google/ExoPlayer/issues/4278)).
 * Fix a bug where download cancellation was ignored
   ([#4403](https://github.com/google/ExoPlayer/issues/4403)).
+* Deprecate `Player.DefaultEventListener` as selective listener overrides can
+  be directly made with the `Player.EventListener` interface.
 
 ### 2.8.2 ###
 

demos/cast/src/main/java/com/google/android/exoplayer2/castdemo/PlayerManager.java

@@ -23,8 +23,8 @@ import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.DefaultRenderersFactory;
 import com.google.android.exoplayer2.ExoPlayerFactory;
 import com.google.android.exoplayer2.Player;
-import com.google.android.exoplayer2.Player.DefaultEventListener;
 import com.google.android.exoplayer2.Player.DiscontinuityReason;
+import com.google.android.exoplayer2.Player.EventListener;
 import com.google.android.exoplayer2.Player.TimelineChangeReason;
 import com.google.android.exoplayer2.RenderersFactory;
 import com.google.android.exoplayer2.SimpleExoPlayer;
@@ -51,11 +51,9 @@ import com.google.android.gms.cast.MediaQueueItem;
 import com.google.android.gms.cast.framework.CastContext;
 import java.util.ArrayList;
 
-/**
- * Manages players and an internal media queue for the ExoPlayer/Cast demo app.
- */
-/* package */ final class PlayerManager extends DefaultEventListener
-    implements CastPlayer.SessionAvailabilityListener {
+/** Manages players and an internal media queue for the ExoPlayer/Cast demo app. */
+/* package */ final class PlayerManager
+    implements EventListener, CastPlayer.SessionAvailabilityListener {
 
   /**
    * Listener for changes in the media queue playback position.

demos/main/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java

@@ -655,7 +655,7 @@ public class PlayerActivity extends Activity
     return false;
   }
 
-  private class PlayerEventListener extends Player.DefaultEventListener {
+  private class PlayerEventListener implements Player.EventListener {
 
     @Override
     public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {

extensions/flac/src/androidTest/java/com/google/android/exoplayer2/ext/flac/FlacPlaybackTest.java

@@ -64,8 +64,7 @@ public class FlacPlaybackTest extends InstrumentationTestCase {
     }
   }
 
-  private static class TestPlaybackRunnable extends Player.DefaultEventListener
-      implements Runnable {
+  private static class TestPlaybackRunnable implements Player.EventListener, Runnable {
 
     private final Context context;
     private final Uri uri;

extensions/ima/src/main/java/com/google/android/exoplayer2/ext/ima/ImaAdsLoader.java

@@ -66,11 +66,15 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 
-/**
- * Loads ads using the IMA SDK. All methods are called on the main thread.
- */
-public final class ImaAdsLoader extends Player.DefaultEventListener implements AdsLoader,
-    VideoAdPlayer, ContentProgressProvider, AdErrorListener, AdsLoadedListener, AdEventListener {
+/** Loads ads using the IMA SDK. All methods are called on the main thread. */
+public final class ImaAdsLoader
+    implements Player.EventListener,
+        AdsLoader,
+        VideoAdPlayer,
+        ContentProgressProvider,
+        AdErrorListener,
+        AdsLoadedListener,
+        AdEventListener {
 
   static {
     ExoPlayerLibraryInfo.registerModule("goog.exo.ima");

extensions/leanback/src/main/java/com/google/android/exoplayer2/ext/leanback/LeanbackPlayerAdapter.java

@@ -248,8 +248,8 @@ public final class LeanbackPlayerAdapter extends PlayerAdapter implements Runnab
     surfaceHolderGlueHost.setSurfaceHolderCallback(null);
   }
 
-  private final class ComponentListener extends Player.DefaultEventListener
-      implements SurfaceHolder.Callback, VideoListener {
+  private final class ComponentListener
+      implements Player.EventListener, SurfaceHolder.Callback, VideoListener {
 
     // SurfaceHolder.Callback implementation.
 

extensions/mediasession/src/main/java/com/google/android/exoplayer2/ext/mediasession/MediaSessionConnector.java

@@ -716,7 +716,7 @@ public final class MediaSessionConnector {
     }
   }
 
-  private class ExoPlayerEventListener extends Player.DefaultEventListener {
+  private class ExoPlayerEventListener implements Player.EventListener {
 
     private int currentWindowIndex;
     private int currentWindowCount;

extensions/opus/src/androidTest/java/com/google/android/exoplayer2/ext/opus/OpusPlaybackTest.java

@@ -64,8 +64,7 @@ public class OpusPlaybackTest extends InstrumentationTestCase {
     }
   }
 
-  private static class TestPlaybackRunnable extends Player.DefaultEventListener
-      implements Runnable {
+  private static class TestPlaybackRunnable implements Player.EventListener, Runnable {
 
     private final Context context;
     private final Uri uri;

extensions/vp9/src/androidTest/java/com/google/android/exoplayer2/ext/vp9/VpxPlaybackTest.java

@@ -95,8 +95,7 @@ public class VpxPlaybackTest extends InstrumentationTestCase {
     }
   }
 
-  private static class TestPlaybackRunnable extends Player.DefaultEventListener
-      implements Runnable {
+  private static class TestPlaybackRunnable implements Player.EventListener, Runnable {
 
     private final Context context;
     private final Uri uri;

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

@@ -215,23 +215,25 @@ public interface Player {
   }
 
   /**
-   * Listener of changes in player state.
+   * Listener of changes in player state. All methods have no-op default implementations to allow
+   * selective overrides.
    */
   interface EventListener {
 
     /**
      * Called when the timeline and/or manifest has been refreshed.
-     * <p>
-     * Note that if the timeline has changed then a position discontinuity may also have occurred.
-     * For example, the current period index may have changed as a result of periods being added or
-     * removed from the timeline. This will <em>not</em> be reported via a separate call to
+     *
+     * <p>Note that if the timeline has changed then a position discontinuity may also have
+     * occurred. For example, the current period index may have changed as a result of periods being
+     * added or removed from the timeline. This will <em>not</em> be reported via a separate call to
      * {@link #onPositionDiscontinuity(int)}.
      *
      * @param timeline The latest timeline. Never null, but may be empty.
      * @param manifest The latest manifest. May be null.
      * @param reason The {@link TimelineChangeReason} responsible for this timeline change.
      */
-    void onTimelineChanged(Timeline timeline, Object manifest, @TimelineChangeReason int reason);
+    default void onTimelineChanged(
+        Timeline timeline, Object manifest, @TimelineChangeReason int reason) {}
 
     /**
      * Called when the available or selected tracks change.
@@ -240,46 +242,47 @@ public interface Player {
      * @param trackSelections The track selections for each renderer. Never null and always of
      *     length {@link #getRendererCount()}, but may contain null elements.
      */
-    void onTracksChanged(TrackGroupArray trackGroups, TrackSelectionArray trackSelections);
+    default void onTracksChanged(
+        TrackGroupArray trackGroups, TrackSelectionArray trackSelections) {}
 
     /**
      * Called when the player starts or stops loading the source.
      *
      * @param isLoading Whether the source is currently being loaded.
      */
-    void onLoadingChanged(boolean isLoading);
+    default void onLoadingChanged(boolean isLoading) {}
 
     /**
-     * Called when the value returned from either {@link #getPlayWhenReady()} or
-     * {@link #getPlaybackState()} changes.
+     * Called when the value returned from either {@link #getPlayWhenReady()} or {@link
+     * #getPlaybackState()} changes.
      *
      * @param playWhenReady Whether playback will proceed when ready.
      * @param playbackState One of the {@code STATE} constants.
      */
-    void onPlayerStateChanged(boolean playWhenReady, int playbackState);
+    default void onPlayerStateChanged(boolean playWhenReady, int playbackState) {}
 
     /**
      * Called when the value of {@link #getRepeatMode()} changes.
      *
      * @param repeatMode The {@link RepeatMode} used for playback.
      */
-    void onRepeatModeChanged(@RepeatMode int repeatMode);
+    default void onRepeatModeChanged(@RepeatMode int repeatMode) {}
 
     /**
      * Called when the value of {@link #getShuffleModeEnabled()} changes.
      *
      * @param shuffleModeEnabled Whether shuffling of windows is enabled.
      */
-    void onShuffleModeEnabledChanged(boolean shuffleModeEnabled);
+    default void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {}
 
     /**
      * Called when an error occurs. The playback state will transition to {@link #STATE_IDLE}
-     * immediately after this method is called. The player instance can still be used, and
-     * {@link #release()} must still be called on the player should it no longer be required.
+     * immediately after this method is called. The player instance can still be used, and {@link
+     * #release()} must still be called on the player should it no longer be required.
      *
      * @param error The error.
      */
-    void onPlayerError(ExoPlaybackException error);
+    default void onPlayerError(ExoPlaybackException error) {}
 
     /**
      * Called when a position discontinuity occurs without a change to the timeline. A position
@@ -287,14 +290,14 @@ public interface Player {
      * transitioning from one period in the timeline to the next), or when the playback position
      * jumps within the period currently being played (as a result of a seek being performed, or
      * when the source introduces a discontinuity internally).
-     * <p>
-     * When a position discontinuity occurs as a result of a change to the timeline this method is
-     * <em>not</em> called. {@link #onTimelineChanged(Timeline, Object, int)} is called in this
+     *
+     * <p>When a position discontinuity occurs as a result of a change to the timeline this method
+     * is <em>not</em> called. {@link #onTimelineChanged(Timeline, Object, int)} is called in this
      * case.
      *
      * @param reason The {@link DiscontinuityReason} responsible for the discontinuity.
      */
-    void onPositionDiscontinuity(@DiscontinuityReason int reason);
+    default void onPositionDiscontinuity(@DiscontinuityReason int reason) {}
 
     /**
      * Called when the current playback parameters change. The playback parameters may change due to
@@ -304,20 +307,21 @@ public interface Player {
      *
      * @param playbackParameters The playback parameters.
      */
-    void onPlaybackParametersChanged(PlaybackParameters playbackParameters);
+    default void onPlaybackParametersChanged(PlaybackParameters playbackParameters) {}
 
     /**
      * Called when all pending seek requests have been processed by the player. This is guaranteed
-     * to happen after any necessary changes to the player state were reported to
-     * {@link #onPlayerStateChanged(boolean, int)}.
+     * to happen after any necessary changes to the player state were reported to {@link
+     * #onPlayerStateChanged(boolean, int)}.
      */
-    void onSeekProcessed();
-
+    default void onSeekProcessed() {}
   }
 
   /**
-   * {@link EventListener} allowing selective overrides. All methods are implemented as no-ops.
+   * @deprecated Use {@link EventListener} interface directly for selective overrides as all methods
+   *     are implemented as no-op default methods.
    */
+  @Deprecated
   abstract class DefaultEventListener implements EventListener {
 
     @Override
@@ -327,60 +331,11 @@ public interface Player {
       onTimelineChanged(timeline, manifest);
     }
 
-    @Override
-    public void onTracksChanged(TrackGroupArray trackGroups, TrackSelectionArray trackSelections) {
-      // Do nothing.
-    }
-
-    @Override
-    public void onLoadingChanged(boolean isLoading) {
-      // Do nothing.
-    }
-
-    @Override
-    public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
-      // Do nothing.
-    }
-
-    @Override
-    public void onRepeatModeChanged(@RepeatMode int repeatMode) {
-      // Do nothing.
-    }
-
-    @Override
-    public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
-      // Do nothing.
-    }
-
-    @Override
-    public void onPlayerError(ExoPlaybackException error) {
-      // Do nothing.
-    }
-
-    @Override
-    public void onPositionDiscontinuity(@DiscontinuityReason int reason) {
-      // Do nothing.
-    }
-
-    @Override
-    public void onPlaybackParametersChanged(PlaybackParameters playbackParameters) {
-      // Do nothing.
-    }
-
-    @Override
-    public void onSeekProcessed() {
-      // Do nothing.
-    }
-
-    /**
-     * @deprecated Use {@link DefaultEventListener#onTimelineChanged(Timeline, Object, int)}
-     *     instead.
-     */
+    /** @deprecated Use {@link EventListener#onTimelineChanged(Timeline, Object, int)} instead. */
     @Deprecated
     public void onTimelineChanged(Timeline timeline, Object manifest) {
       // Do nothing.
     }
-
   }
 
   /**

library/core/src/test/java/com/google/android/exoplayer2/ExoPlayerTest.java

@@ -19,7 +19,6 @@ import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.fail;
 
 import android.view.Surface;
-import com.google.android.exoplayer2.Player.DefaultEventListener;
 import com.google.android.exoplayer2.Player.EventListener;
 import com.google.android.exoplayer2.Timeline.Window;
 import com.google.android.exoplayer2.source.ConcatenatingMediaSource;
@@ -483,7 +482,7 @@ public final class ExoPlayerTest {
             .build();
     final List<Integer> playbackStatesWhenSeekProcessed = new ArrayList<>();
     EventListener eventListener =
-        new DefaultEventListener() {
+        new EventListener() {
           private int currentPlaybackState = Player.STATE_IDLE;
 
           @Override
@@ -535,7 +534,7 @@ public final class ExoPlayerTest {
             .build();
     final boolean[] onSeekProcessedCalled = new boolean[1];
     EventListener listener =
-        new DefaultEventListener() {
+        new EventListener() {
           @Override
           public void onSeekProcessed() {
             onSeekProcessedCalled[0] = true;
@@ -1988,7 +1987,7 @@ public final class ExoPlayerTest {
     final List<Integer> eventListener1States = new ArrayList<>();
     final List<Integer> eventListener2States = new ArrayList<>();
     final EventListener eventListener1 =
-        new DefaultEventListener() {
+        new EventListener() {
           @Override
           public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
             eventListener1States.add(playbackState);
@@ -1998,7 +1997,7 @@ public final class ExoPlayerTest {
           }
         };
     final EventListener eventListener2 =
-        new DefaultEventListener() {
+        new EventListener() {
           @Override
           public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
             eventListener2States.add(playbackState);
@@ -2038,7 +2037,7 @@ public final class ExoPlayerTest {
     final List<Boolean> eventListenerPlayWhenReady = new ArrayList<>();
     final List<Integer> eventListenerStates = new ArrayList<>();
     final EventListener eventListener =
-        new DefaultEventListener() {
+        new EventListener() {
           @Override
           public void onTimelineChanged(Timeline timeline, Object manifest, int reason) {
             if (timeline.isEmpty()) {

library/ui/src/main/java/com/google/android/exoplayer2/ui/DebugTextViewHelper.java

@@ -27,7 +27,7 @@ import java.util.Locale;
  * A helper class for periodically updating a {@link TextView} with debug information obtained from
  * a {@link SimpleExoPlayer}.
  */
-public class DebugTextViewHelper extends Player.DefaultEventListener implements Runnable {
+public class DebugTextViewHelper implements Player.EventListener, Runnable {
 
   private static final int REFRESH_INTERVAL_MS = 1000;
 

library/ui/src/main/java/com/google/android/exoplayer2/ui/PlayerControlView.java

@@ -1030,8 +1030,8 @@ public class PlayerControlView extends FrameLayout {
     return true;
   }
 
-  private final class ComponentListener extends Player.DefaultEventListener
-      implements TimeBar.OnScrubListener, OnClickListener {
+  private final class ComponentListener
+      implements Player.EventListener, TimeBar.OnScrubListener, OnClickListener {
 
     @Override
     public void onScrubStart(TimeBar timeBar, long position) {

library/ui/src/main/java/com/google/android/exoplayer2/ui/PlayerNotificationManager.java

@@ -937,7 +937,7 @@ public class PlayerNotificationManager {
     return actions;
   }
 
-  private class PlayerListener extends Player.DefaultEventListener {
+  private class PlayerListener implements Player.EventListener {
 
     @Override
     public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {

library/ui/src/main/java/com/google/android/exoplayer2/ui/PlayerView.java

@@ -1179,8 +1179,8 @@ public class PlayerView extends FrameLayout {
         || keyCode == KeyEvent.KEYCODE_DPAD_CENTER;
   }
 
-  private final class ComponentListener extends Player.DefaultEventListener
-      implements TextOutput, VideoListener, OnLayoutChangeListener {
+  private final class ComponentListener
+      implements Player.EventListener, TextOutput, VideoListener, OnLayoutChangeListener {
 
     // TextOutput implementation
 

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

@@ -572,7 +572,7 @@ public abstract class Action {
         return;
       }
       Player.EventListener listener =
-          new Player.DefaultEventListener() {
+          new Player.EventListener() {
             @Override
             public void onTimelineChanged(
                 Timeline timeline, Object manifest, @Player.TimelineChangeReason int reason) {
@@ -618,13 +618,14 @@ public abstract class Action {
       if (nextAction == null) {
         return;
       }
-      player.addListener(new Player.DefaultEventListener() {
-        @Override
-        public void onPositionDiscontinuity(@Player.DiscontinuityReason int reason) {
-          player.removeListener(this);
-          nextAction.schedule(player, trackSelector, surface, handler);
-        }
-      });
+      player.addListener(
+          new Player.EventListener() {
+            @Override
+            public void onPositionDiscontinuity(@Player.DiscontinuityReason int reason) {
+              player.removeListener(this);
+              nextAction.schedule(player, trackSelector, surface, handler);
+            }
+          });
     }
 
     @Override
@@ -663,15 +664,16 @@ public abstract class Action {
       if (targetPlaybackState == player.getPlaybackState()) {
         nextAction.schedule(player, trackSelector, surface, handler);
       } else {
-        player.addListener(new Player.DefaultEventListener() {
-          @Override
-          public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
-            if (targetPlaybackState == playbackState) {
-              player.removeListener(this);
-              nextAction.schedule(player, trackSelector, surface, handler);
-            }
-          }
-        });
+        player.addListener(
+            new Player.EventListener() {
+              @Override
+              public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
+                if (targetPlaybackState == playbackState) {
+                  player.removeListener(this);
+                  nextAction.schedule(player, trackSelector, surface, handler);
+                }
+              }
+            });
       }
     }
 
@@ -704,13 +706,14 @@ public abstract class Action {
       if (nextAction == null) {
         return;
       }
-      player.addListener(new Player.DefaultEventListener() {
-        @Override
-        public void onSeekProcessed() {
-          player.removeListener(this);
-          nextAction.schedule(player, trackSelector, surface, handler);
-        }
-      });
+      player.addListener(
+          new Player.EventListener() {
+            @Override
+            public void onSeekProcessed() {
+              player.removeListener(this);
+              nextAction.schedule(player, trackSelector, surface, handler);
+            }
+          });
     }
 
     @Override

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

@@ -49,11 +49,12 @@ import com.google.android.exoplayer2.util.HandlerWrapper;
 import com.google.android.exoplayer2.util.Util;
 import com.google.android.exoplayer2.video.VideoRendererEventListener;
 
-/**
- * A {@link HostedTest} for {@link ExoPlayer} playback tests.
- */
-public abstract class ExoHostedTest extends Player.DefaultEventListener implements HostedTest,
-    AudioRendererEventListener, VideoRendererEventListener {
+/** A {@link HostedTest} for {@link ExoPlayer} playback tests. */
+public abstract class ExoHostedTest
+    implements Player.EventListener,
+        HostedTest,
+        AudioRendererEventListener,
+        VideoRendererEventListener {
 
   static {
     // DefaultAudioSink is able to work around spurious timestamps reported by the platform (by

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

@@ -51,11 +51,8 @@ import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
 
-/**
- * Helper class to run an ExoPlayer test.
- */
-public final class ExoPlayerTestRunner extends Player.DefaultEventListener
-    implements ActionSchedule.Callback {
+/** Helper class to run an ExoPlayer test. */
+public final class ExoPlayerTestRunner implements Player.EventListener, ActionSchedule.Callback {
 
   /**
    * Builder to set-up a {@link ExoPlayerTestRunner}. Default fake implementations will be used for