Automated g4 rollback of changelist 192816182.

*** Reason for rollback ***

Added the missing initialization to Timeline.EMPTY.

*** Original change description ***

Automated g4 rollback of changelist 192742299.

*** Reason for rollback ***

Culprit for b/78018932.

*** Original change description ***

Auto-register analytics collector in SimpleExoPlayer.

This automatically registers and deregisters an analytics collector in
SimpleExoPlayer. Doing this also allows to write integration tests checking
whether the reported window indices and media period ids are correct.

***

***

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=193006701

RELEASENOTES.md

@@ -7,6 +7,8 @@
 * Moved initial bitrate estimate from `AdaptiveTrackSelection` to
   `DefaultBandwidthMeter`.
 * Updated default max buffer length in `DefaultLoadControl`.
+* Added `AnalyticsListener` interface which can be registered in
+  `SimpleExoPlayer` to receive detailed meta data for each ExoPlayer event.
 * UI components:
   * Add support for listening to `AspectRatioFrameLayout`'s aspect ratio update
     ([#3736](https://github.com/google/ExoPlayer/issues/3736)).

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

@@ -17,6 +17,7 @@ package com.google.android.exoplayer2;
 
 import android.content.Context;
 import android.support.annotation.Nullable;
+import com.google.android.exoplayer2.analytics.AnalyticsCollector;
 import com.google.android.exoplayer2.drm.DrmSessionManager;
 import com.google.android.exoplayer2.drm.FrameworkMediaCrypto;
 import com.google.android.exoplayer2.trackselection.TrackSelector;
@@ -175,6 +176,27 @@ public final class ExoPlayerFactory {
     return new SimpleExoPlayer(renderersFactory, trackSelector, loadControl, drmSessionManager);
   }
 
+  /**
+   * Creates a {@link SimpleExoPlayer} instance.
+   *
+   * @param renderersFactory A factory for creating {@link Renderer}s to be used by the instance.
+   * @param trackSelector The {@link TrackSelector} that will be used by the instance.
+   * @param loadControl The {@link LoadControl} that will be used by the instance.
+   * @param drmSessionManager An optional {@link DrmSessionManager}. May be null if the instance
+   *     will not be used for DRM protected playbacks.
+   * @param analyticsCollectorFactory A factory for creating the {@link AnalyticsCollector} that
+   *     will collect and forward all player events.
+   */
+  public static SimpleExoPlayer newSimpleInstance(
+      RenderersFactory renderersFactory,
+      TrackSelector trackSelector,
+      LoadControl loadControl,
+      @Nullable DrmSessionManager<FrameworkMediaCrypto> drmSessionManager,
+      AnalyticsCollector.Factory analyticsCollectorFactory) {
+    return new SimpleExoPlayer(
+        renderersFactory, trackSelector, loadControl, drmSessionManager, analyticsCollectorFactory);
+  }
+
   /**
    * Creates an {@link ExoPlayer} instance.
    *

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

@@ -27,9 +27,12 @@ import android.view.Surface;
 import android.view.SurfaceHolder;
 import android.view.SurfaceView;
 import android.view.TextureView;
+import com.google.android.exoplayer2.analytics.AnalyticsCollector;
+import com.google.android.exoplayer2.analytics.AnalyticsListener;
 import com.google.android.exoplayer2.audio.AudioAttributes;
 import com.google.android.exoplayer2.audio.AudioRendererEventListener;
 import com.google.android.exoplayer2.decoder.DecoderCounters;
+import com.google.android.exoplayer2.drm.DefaultDrmSessionManager;
 import com.google.android.exoplayer2.drm.DrmSessionManager;
 import com.google.android.exoplayer2.drm.FrameworkMediaCrypto;
 import com.google.android.exoplayer2.metadata.Metadata;
@@ -63,6 +66,7 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
   protected final Renderer[] renderers;
 
   private final ExoPlayer player;
+  private final Handler eventHandler;
   private final ComponentListener componentListener;
   private final CopyOnWriteArraySet<com.google.android.exoplayer2.video.VideoListener>
       videoListeners;
@@ -70,6 +74,7 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
   private final CopyOnWriteArraySet<MetadataOutput> metadataOutputs;
   private final CopyOnWriteArraySet<VideoRendererEventListener> videoDebugListeners;
   private final CopyOnWriteArraySet<AudioRendererEventListener> audioDebugListeners;
+  private final AnalyticsCollector analyticsCollector;
 
   private Format videoFormat;
   private Format audioFormat;
@@ -85,6 +90,7 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
   private int audioSessionId;
   private AudioAttributes audioAttributes;
   private float audioVolume;
+  private MediaSource mediaSource;
 
   /**
    * @param renderersFactory A factory for creating {@link Renderer}s to be used by the instance.
@@ -98,7 +104,12 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
       TrackSelector trackSelector,
       LoadControl loadControl,
       @Nullable DrmSessionManager<FrameworkMediaCrypto> drmSessionManager) {
-    this(renderersFactory, trackSelector, loadControl, drmSessionManager, Clock.DEFAULT);
+    this(
+        renderersFactory,
+        trackSelector,
+        loadControl,
+        drmSessionManager,
+        new AnalyticsCollector.Factory());
   }
 
   /**
@@ -107,6 +118,32 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
    * @param loadControl The {@link LoadControl} that will be used by the instance.
    * @param drmSessionManager An optional {@link DrmSessionManager}. May be null if the instance
    *     will not be used for DRM protected playbacks.
+   * @param analyticsCollectorFactory A factory for creating the {@link AnalyticsCollector} that
+   *     will collect and forward all player events.
+   */
+  protected SimpleExoPlayer(
+      RenderersFactory renderersFactory,
+      TrackSelector trackSelector,
+      LoadControl loadControl,
+      @Nullable DrmSessionManager<FrameworkMediaCrypto> drmSessionManager,
+      AnalyticsCollector.Factory analyticsCollectorFactory) {
+    this(
+        renderersFactory,
+        trackSelector,
+        loadControl,
+        drmSessionManager,
+        analyticsCollectorFactory,
+        Clock.DEFAULT);
+  }
+
+  /**
+   * @param renderersFactory A factory for creating {@link Renderer}s to be used by the instance.
+   * @param trackSelector The {@link TrackSelector} that will be used by the instance.
+   * @param loadControl The {@link LoadControl} that will be used by the instance.
+   * @param drmSessionManager An optional {@link DrmSessionManager}. May be null if the instance
+   *     will not be used for DRM protected playbacks.
+   * @param analyticsCollectorFactory A factory for creating the {@link AnalyticsCollector} that
+   *     will collect and forward all player events.
    * @param clock The {@link Clock} that will be used by the instance. Should always be {@link
    *     Clock#DEFAULT}, unless the player is being used from a test.
    */
@@ -115,6 +152,7 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
       TrackSelector trackSelector,
       LoadControl loadControl,
       @Nullable DrmSessionManager<FrameworkMediaCrypto> drmSessionManager,
+      AnalyticsCollector.Factory analyticsCollectorFactory,
       Clock clock) {
     componentListener = new ComponentListener();
     videoListeners = new CopyOnWriteArraySet<>();
@@ -123,7 +161,7 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
     videoDebugListeners = new CopyOnWriteArraySet<>();
     audioDebugListeners = new CopyOnWriteArraySet<>();
     Looper eventLooper = Looper.myLooper() != null ? Looper.myLooper() : Looper.getMainLooper();
-    Handler eventHandler = new Handler(eventLooper);
+    eventHandler = new Handler(eventLooper);
     renderers =
         renderersFactory.createRenderers(
             eventHandler,
@@ -141,6 +179,14 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
 
     // Build the player and associated objects.
     player = createExoPlayerImpl(renderers, trackSelector, loadControl, clock);
+    analyticsCollector = analyticsCollectorFactory.createAnalyticsCollector(player, clock);
+    addListener(analyticsCollector);
+    addVideoDebugListener(analyticsCollector);
+    addAudioDebugListener(analyticsCollector);
+    addMetadataOutput(analyticsCollector);
+    if (drmSessionManager instanceof DefaultDrmSessionManager) {
+      ((DefaultDrmSessionManager) drmSessionManager).addListener(eventHandler, analyticsCollector);
+    }
   }
 
   @Override
@@ -283,6 +329,29 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
     return Util.getStreamTypeForAudioUsage(audioAttributes.usage);
   }
 
+  /** Returns the {@link AnalyticsCollector} used for collecting analytics events. */
+  public AnalyticsCollector getAnalyticsCollector() {
+    return analyticsCollector;
+  }
+
+  /**
+   * Adds an {@link AnalyticsListener} to receive analytics events.
+   *
+   * @param listener The listener to be added.
+   */
+  public void addAnalyticsListener(AnalyticsListener listener) {
+    analyticsCollector.addListener(listener);
+  }
+
+  /**
+   * Removes an {@link AnalyticsListener}.
+   *
+   * @param listener The listener to be removed.
+   */
+  public void removeAnalyticsListener(AnalyticsListener listener) {
+    analyticsCollector.removeListener(listener);
+  }
+
   /**
    * Sets the attributes for audio playback, used by the underlying audio track. If not set, the
    * default audio attributes will be used. They are suitable for general media playback.
@@ -586,11 +655,19 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
 
   @Override
   public void prepare(MediaSource mediaSource) {
-    player.prepare(mediaSource);
+    prepare(mediaSource, /* resetPosition= */ true, /* resetState= */ true);
   }
 
   @Override
   public void prepare(MediaSource mediaSource, boolean resetPosition, boolean resetState) {
+    if (this.mediaSource != mediaSource) {
+      if (this.mediaSource != null) {
+        this.mediaSource.removeEventListener(analyticsCollector);
+        analyticsCollector.resetForNewMediaSource();
+      }
+      mediaSource.addEventListener(eventHandler, analyticsCollector);
+      this.mediaSource = mediaSource;
+    }
     player.prepare(mediaSource, resetPosition, resetState);
   }
 
@@ -631,21 +708,25 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
 
   @Override
   public void seekToDefaultPosition() {
+    analyticsCollector.notifySeekStarted();
     player.seekToDefaultPosition();
   }
 
   @Override
   public void seekToDefaultPosition(int windowIndex) {
+    analyticsCollector.notifySeekStarted();
     player.seekToDefaultPosition(windowIndex);
   }
 
   @Override
   public void seekTo(long positionMs) {
+    analyticsCollector.notifySeekStarted();
     player.seekTo(positionMs);
   }
 
   @Override
   public void seekTo(int windowIndex, long positionMs) {
+    analyticsCollector.notifySeekStarted();
     player.seekTo(windowIndex, positionMs);
   }
 
@@ -671,12 +752,17 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
 
   @Override
   public void stop() {
-    player.stop();
+    stop(/* reset= */ false);
   }
 
   @Override
   public void stop(boolean reset) {
     player.stop(reset);
+    if (mediaSource != null) {
+      mediaSource.removeEventListener(analyticsCollector);
+      mediaSource = null;
+      analyticsCollector.resetForNewMediaSource();
+    }
   }
 
   @Override
@@ -689,6 +775,9 @@ public class SimpleExoPlayer implements ExoPlayer, Player.VideoComponent, Player
       }
       surface = null;
     }
+    if (mediaSource != null) {
+      mediaSource.removeEventListener(analyticsCollector);
+    }
   }
 
   @Override

library/core/src/main/java/com/google/android/exoplayer2/analytics/AnalyticsCollector.java

@@ -44,6 +44,7 @@ import com.google.android.exoplayer2.video.VideoRendererEventListener;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
+import java.util.List;
 import java.util.Set;
 import java.util.concurrent.CopyOnWriteArraySet;
 
@@ -157,6 +158,22 @@ public class AnalyticsCollector
     }
   }
 
+  /**
+   * Resets the analytics collector for a new media source. Should be called before the player is
+   * prepared with a new media source.
+   */
+  public final void resetForNewMediaSource() {
+    // Copying the list is needed because onMediaPeriodReleased will modify the list.
+    List<MediaPeriodId> activeMediaPeriods =
+        new ArrayList<>(mediaPeriodQueueTracker.activeMediaPeriods);
+    Timeline timeline = mediaPeriodQueueTracker.timeline;
+    for (MediaPeriodId mediaPeriod : activeMediaPeriods) {
+      int windowIndex =
+          timeline.isEmpty() ? 0 : timeline.getPeriod(mediaPeriod.periodIndex, period).windowIndex;
+      onMediaPeriodReleased(windowIndex, mediaPeriod);
+    }
+  }
+
   // MetadataOutput implementation.
 
   @Override
@@ -631,6 +648,9 @@ public class AnalyticsCollector
   /** Keeps track of the active media periods and currently playing and reading media period. */
   private static final class MediaPeriodQueueTracker {
 
+    // TODO: Investigate reporting MediaPeriodId in renderer events and adding a listener of queue
+    // changes, which would hopefully remove the need to track the queue here.
+
     private final ArrayList<MediaPeriodId> activeMediaPeriods;
     private final Period period;
 
@@ -642,6 +662,7 @@ public class AnalyticsCollector
     public MediaPeriodQueueTracker() {
       activeMediaPeriods = new ArrayList<>();
       period = new Period();
+      timeline = Timeline.EMPTY;
     }
 
     /**
@@ -763,13 +784,14 @@ public class AnalyticsCollector
     }
 
     private void updateLastReportedPlayingMediaPeriod() {
-      lastReportedPlayingMediaPeriod =
+      if (!activeMediaPeriods.isEmpty()) {
-          activeMediaPeriods.isEmpty() ? null : activeMediaPeriods.get(0);
+        lastReportedPlayingMediaPeriod = activeMediaPeriods.get(0);
+      }
     }
 
     private MediaPeriodId updateMediaPeriodIdToNewTimeline(
         MediaPeriodId mediaPeriodId, Timeline newTimeline) {
-      if (newTimeline.isEmpty()) {
+      if (newTimeline.isEmpty() || timeline.isEmpty()) {
         return mediaPeriodId;
       }
       Object uid = timeline.getPeriod(mediaPeriodId.periodIndex, period, /* setIds= */ true).uid;

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

@@ -28,6 +28,8 @@ import com.google.android.exoplayer2.Renderer;
 import com.google.android.exoplayer2.RenderersFactory;
 import com.google.android.exoplayer2.SimpleExoPlayer;
 import com.google.android.exoplayer2.Timeline;
+import com.google.android.exoplayer2.analytics.AnalyticsCollector;
+import com.google.android.exoplayer2.analytics.AnalyticsListener;
 import com.google.android.exoplayer2.audio.AudioRendererEventListener;
 import com.google.android.exoplayer2.drm.DrmSessionManager;
 import com.google.android.exoplayer2.drm.FrameworkMediaCrypto;
@@ -86,6 +88,7 @@ public final class ExoPlayerTestRunner extends Player.DefaultEventListener
     private Player.EventListener eventListener;
     private VideoRendererEventListener videoRendererEventListener;
     private AudioRendererEventListener audioRendererEventListener;
+    private AnalyticsListener analyticsListener;
     private Integer expectedPlayerEndedCount;
 
     /**
@@ -261,6 +264,17 @@ public final class ExoPlayerTestRunner extends Player.DefaultEventListener
       return this;
     }
 
+    /**
+     * Sets an {@link AnalyticsListener} to be registered.
+     *
+     * @param analyticsListener An {@link AnalyticsListener} to be registered.
+     * @return This builder.
+     */
+    public Builder setAnalyticsListener(AnalyticsListener analyticsListener) {
+      this.analyticsListener = analyticsListener;
+      return this;
+    }
+
     /**
      * Sets the number of times the test runner is expected to reach the {@link Player#STATE_ENDED}
      * or {@link Player#STATE_IDLE}. The default is 1. This affects how long
@@ -330,6 +344,7 @@ public final class ExoPlayerTestRunner extends Player.DefaultEventListener
           eventListener,
           videoRendererEventListener,
           audioRendererEventListener,
+          analyticsListener,
           expectedPlayerEndedCount);
     }
   }
@@ -343,6 +358,7 @@ public final class ExoPlayerTestRunner extends Player.DefaultEventListener
   private final @Nullable Player.EventListener eventListener;
   private final @Nullable VideoRendererEventListener videoRendererEventListener;
   private final @Nullable AudioRendererEventListener audioRendererEventListener;
+  private final @Nullable AnalyticsListener analyticsListener;
 
   private final HandlerThread playerThread;
   private final HandlerWrapper handler;
@@ -369,6 +385,7 @@ public final class ExoPlayerTestRunner extends Player.DefaultEventListener
       @Nullable Player.EventListener eventListener,
       @Nullable VideoRendererEventListener videoRendererEventListener,
       @Nullable AudioRendererEventListener audioRendererEventListener,
+      @Nullable AnalyticsListener analyticsListener,
       int expectedPlayerEndedCount) {
     this.clock = clock;
     this.mediaSource = mediaSource;
@@ -379,6 +396,7 @@ public final class ExoPlayerTestRunner extends Player.DefaultEventListener
     this.eventListener = eventListener;
     this.videoRendererEventListener = videoRendererEventListener;
     this.audioRendererEventListener = audioRendererEventListener;
+    this.analyticsListener = analyticsListener;
     this.timelines = new ArrayList<>();
     this.manifests = new ArrayList<>();
     this.timelineChangeReasons = new ArrayList<>();
@@ -417,6 +435,9 @@ public final class ExoPlayerTestRunner extends Player.DefaultEventListener
               if (audioRendererEventListener != null) {
                 player.addAudioDebugListener(audioRendererEventListener);
               }
+              if (analyticsListener != null) {
+                player.addAnalyticsListener(analyticsListener);
+              }
               player.setPlayWhenReady(true);
               if (actionSchedule != null) {
                 actionSchedule.start(
@@ -636,7 +657,13 @@ public final class ExoPlayerTestRunner extends Player.DefaultEventListener
         TrackSelector trackSelector,
         LoadControl loadControl,
         Clock clock) {
-      super(renderersFactory, trackSelector, loadControl, /* drmSessionManager= */ null, clock);
+      super(
+          renderersFactory,
+          trackSelector,
+          loadControl,
+          /* drmSessionManager= */ null,
+          new AnalyticsCollector.Factory(),
+          clock);
     }
   }
 }

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

@@ -85,6 +85,7 @@ public class FakeRenderer extends BaseRenderer {
       if (result == C.RESULT_FORMAT_READ) {
         formatReadCount++;
         assertThat(expectedFormats).contains(formatHolder.format);
+        onFormatChanged(formatHolder.format);
       } else if (result == C.RESULT_BUFFER_READ) {
         if (buffer.isEndOfStream()) {
           isEnded = true;
@@ -92,6 +93,7 @@ public class FakeRenderer extends BaseRenderer {
         }
         lastSamplePositionUs = buffer.timeUs;
         sampleBufferReadCount++;
+        onBufferRead();
       } else {
         Assertions.checkState(result == C.RESULT_NOTHING_READ);
         return;
@@ -115,4 +117,9 @@ public class FakeRenderer extends BaseRenderer {
         ? (FORMAT_HANDLED | ADAPTIVE_SEAMLESS) : FORMAT_UNSUPPORTED_TYPE;
   }
 
+  /** Called when the renderer reads a new format. */
+  protected void onFormatChanged(Format format) {}
+
+  /** Called when the renderer read a sample from the buffer. */
+  protected void onBufferRead() {}
 }