Remove player and isTopLevelSource parameters from MediaSource.prepare.

They are not longer needed anywhere, are error-prone (because of threading
requirements), and complicate testing and using MediaSources without a player.

PiperOrigin-RevId: 227871157

RELEASENOTES.md

@@ -40,6 +40,7 @@
   ([#5240](https://github.com/google/ExoPlayer/issues/5240)).
 * Add `Handler` parameter to `ConcatenatingMediaSource` methods which take a
   callback `Runnable`.
+* Remove `player` and `isTopLevelSource` parameters from `MediaSource.prepare`.
 
 ### 2.9.3 ###
 

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

@@ -18,7 +18,6 @@ package com.google.android.exoplayer2.ext.ima;
 import android.os.Handler;
 import android.support.annotation.Nullable;
 import android.view.ViewGroup;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.source.BaseMediaSource;
 import com.google.android.exoplayer2.source.MediaPeriod;
@@ -33,7 +32,8 @@ import java.io.IOException;
 /**
  * A {@link MediaSource} that inserts ads linearly with a provided content media source.
  *
- * @deprecated Use com.google.android.exoplayer2.source.ads.AdsMediaSource with ImaAdsLoader.
+ * @deprecated Use {@link com.google.android.exoplayer2.source.ads.AdsMediaSource} with
+ *     ImaAdsLoader.
  */
 @Deprecated
 public final class ImaAdsMediaSource extends BaseMediaSource implements SourceInfoRefreshListener {
@@ -83,12 +83,8 @@ public final class ImaAdsMediaSource extends BaseMediaSource implements SourceIn
   }
 
   @Override
-  public void prepareSourceInternal(
-      final ExoPlayer player,
-      boolean isTopLevelSource,
-      @Nullable TransferListener mediaTransferListener) {
-    adsMediaSource.prepareSource(
-        player, isTopLevelSource, /* listener= */ this, mediaTransferListener);
+  public void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
+    adsMediaSource.prepareSource(/* listener= */ this, mediaTransferListener);
   }
 
   @Override

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

@@ -139,7 +139,6 @@ import java.util.concurrent.CopyOnWriteArrayList;
             repeatMode,
             shuffleModeEnabled,
             eventHandler,
-            this,
             clock);
     internalPlayerHandler = new Handler(internalPlayer.getPlaybackLooper());
   }

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

@@ -95,7 +95,6 @@ import java.util.concurrent.atomic.AtomicBoolean;
   private final HandlerWrapper handler;
   private final HandlerThread internalPlaybackThread;
   private final Handler eventHandler;
-  private final ExoPlayer player;
   private final Timeline.Window window;
   private final Timeline.Period period;
   private final long backBufferDurationUs;
@@ -134,7 +133,6 @@ import java.util.concurrent.atomic.AtomicBoolean;
       @Player.RepeatMode int repeatMode,
       boolean shuffleModeEnabled,
       Handler eventHandler,
-      ExoPlayer player,
       Clock clock) {
     this.renderers = renderers;
     this.trackSelector = trackSelector;
@@ -145,7 +143,6 @@ import java.util.concurrent.atomic.AtomicBoolean;
     this.repeatMode = repeatMode;
     this.shuffleModeEnabled = shuffleModeEnabled;
     this.eventHandler = eventHandler;
-    this.player = player;
     this.clock = clock;
     this.queue = new MediaPeriodQueue();
 
@@ -441,11 +438,7 @@ import java.util.concurrent.atomic.AtomicBoolean;
     loadControl.onPrepared();
     this.mediaSource = mediaSource;
     setState(Player.STATE_BUFFERING);
-    mediaSource.prepareSource(
-        player,
-        /* isTopLevelSource= */ true,
-        /* listener= */ this,
-        bandwidthMeter.getTransferListener());
+    mediaSource.prepareSource(/* listener= */ this, bandwidthMeter.getTransferListener());
     handler.sendEmptyMessage(MSG_DO_SOME_WORK);
   }
 

library/core/src/main/java/com/google/android/exoplayer2/source/BaseMediaSource.java

@@ -16,8 +16,8 @@
 package com.google.android.exoplayer2.source;
 
 import android.os.Handler;
+import android.os.Looper;
 import android.support.annotation.Nullable;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.upstream.TransferListener;
 import com.google.android.exoplayer2.util.Assertions;
@@ -35,9 +35,9 @@ public abstract class BaseMediaSource implements MediaSource {
   private final ArrayList<SourceInfoRefreshListener> sourceInfoListeners;
   private final MediaSourceEventListener.EventDispatcher eventDispatcher;
 
-  private @Nullable ExoPlayer player;
-  private @Nullable Timeline timeline;
-  private @Nullable Object manifest;
+  @Nullable private Looper looper;
+  @Nullable private Timeline timeline;
+  @Nullable private Object manifest;
 
   public BaseMediaSource() {
     sourceInfoListeners = new ArrayList<>(/* initialCapacity= */ 1);
@@ -48,21 +48,16 @@ public abstract class BaseMediaSource implements MediaSource {
    * Starts source preparation. This method is called at most once until the next call to {@link
    * #releaseSourceInternal()}.
    *
-   * @param player The player for which this source is being prepared.
-   * @param isTopLevelSource Whether this source has been passed directly to {@link
-   *     ExoPlayer#prepare(MediaSource)} or {@link ExoPlayer#prepare(MediaSource, boolean,
-   *     boolean)}.
    * @param mediaTransferListener The transfer listener which should be informed of any media data
    *     transfers. May be null if no listener is available. Note that this listener should usually
    *     be only informed of transfers related to the media loads and not of auxiliary loads for
    *     manifests and other data.
    */
-  protected abstract void prepareSourceInternal(
-      ExoPlayer player, boolean isTopLevelSource, @Nullable TransferListener mediaTransferListener);
+  protected abstract void prepareSourceInternal(@Nullable TransferListener mediaTransferListener);
 
   /**
    * Releases the source. This method is called exactly once after each call to {@link
-   * #prepareSourceInternal(ExoPlayer, boolean, TransferListener)}.
+   * #prepareSourceInternal(TransferListener)}.
    */
   protected abstract void releaseSourceInternal();
 
@@ -135,15 +130,14 @@ public abstract class BaseMediaSource implements MediaSource {
 
   @Override
   public final void prepareSource(
-      ExoPlayer player,
-      boolean isTopLevelSource,
       SourceInfoRefreshListener listener,
       @Nullable TransferListener mediaTransferListener) {
-    Assertions.checkArgument(this.player == null || this.player == player);
+    Looper looper = Looper.myLooper();
+    Assertions.checkArgument(this.looper == null || this.looper == looper);
     sourceInfoListeners.add(listener);
-    if (this.player == null) {
-      this.player = player;
-      prepareSourceInternal(player, isTopLevelSource, mediaTransferListener);
+    if (this.looper == null) {
+      this.looper = looper;
+      prepareSourceInternal(mediaTransferListener);
     } else if (timeline != null) {
       listener.onSourceInfoRefreshed(/* source= */ this, timeline, manifest);
     }
@@ -153,7 +147,7 @@ public abstract class BaseMediaSource implements MediaSource {
   public final void releaseSource(SourceInfoRefreshListener listener) {
     sourceInfoListeners.remove(listener);
     if (sourceInfoListeners.isEmpty()) {
-      player = null;
+      looper = null;
       timeline = null;
       manifest = null;
       releaseSourceInternal();

library/core/src/main/java/com/google/android/exoplayer2/source/ClippingMediaSource.java

@@ -18,7 +18,6 @@ package com.google.android.exoplayer2.source;
 import android.support.annotation.IntDef;
 import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.upstream.Allocator;
 import com.google.android.exoplayer2.upstream.TransferListener;
@@ -193,11 +192,8 @@ public final class ClippingMediaSource extends CompositeMediaSource<Void> {
   }
 
   @Override
-  public void prepareSourceInternal(
-      ExoPlayer player,
-      boolean isTopLevelSource,
-      @Nullable TransferListener mediaTransferListener) {
-    super.prepareSourceInternal(player, isTopLevelSource, mediaTransferListener);
+  public void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
+    super.prepareSourceInternal(mediaTransferListener);
     prepareChildSource(/* id= */ null, mediaSource);
   }
 

library/core/src/main/java/com/google/android/exoplayer2/source/CompositeMediaSource.java

@@ -18,7 +18,6 @@ package com.google.android.exoplayer2.source;
 import android.os.Handler;
 import android.support.annotation.CallSuper;
 import android.support.annotation.Nullable;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.upstream.TransferListener;
 import com.google.android.exoplayer2.util.Assertions;
@@ -35,7 +34,6 @@ public abstract class CompositeMediaSource<T> extends BaseMediaSource {
 
   private final HashMap<T, MediaSourceAndListener> childSources;
 
-  private @Nullable ExoPlayer player;
   private @Nullable Handler eventHandler;
   private @Nullable TransferListener mediaTransferListener;
 
@@ -46,11 +44,7 @@ public abstract class CompositeMediaSource<T> extends BaseMediaSource {
 
   @Override
   @CallSuper
-  public void prepareSourceInternal(
-      ExoPlayer player,
-      boolean isTopLevelSource,
-      @Nullable TransferListener mediaTransferListener) {
-    this.player = player;
+  public void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
     this.mediaTransferListener = mediaTransferListener;
     eventHandler = new Handler();
   }
@@ -71,7 +65,6 @@ public abstract class CompositeMediaSource<T> extends BaseMediaSource {
       childSource.mediaSource.removeEventListener(childSource.eventListener);
     }
     childSources.clear();
-    player = null;
   }
 
   /**
@@ -105,11 +98,7 @@ public abstract class CompositeMediaSource<T> extends BaseMediaSource {
     MediaSourceEventListener eventListener = new ForwardingEventListener(id);
     childSources.put(id, new MediaSourceAndListener(mediaSource, sourceListener, eventListener));
     mediaSource.addEventListener(Assertions.checkNotNull(eventHandler), eventListener);
-    mediaSource.prepareSource(
-        Assertions.checkNotNull(player),
-        /* isTopLevelSource= */ false,
-        sourceListener,
-        mediaTransferListener);
+    mediaSource.prepareSource(sourceListener, mediaTransferListener);
   }
 
   /**

library/core/src/main/java/com/google/android/exoplayer2/source/ConcatenatingMediaSource.java

@@ -22,7 +22,6 @@ import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.util.Pair;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.source.ConcatenatingMediaSource.MediaSourceHolder;
 import com.google.android.exoplayer2.source.ShuffleOrder.DefaultShuffleOrder;
@@ -419,10 +418,8 @@ public class ConcatenatingMediaSource extends CompositeMediaSource<MediaSourceHo
 
   @Override
   public final synchronized void prepareSourceInternal(
-      ExoPlayer player,
-      boolean isTopLevelSource,
       @Nullable TransferListener mediaTransferListener) {
-    super.prepareSourceInternal(player, isTopLevelSource, mediaTransferListener);
+    super.prepareSourceInternal(mediaTransferListener);
     playbackThreadHandler = new Handler(/* callback= */ this::handleMessage);
     if (mediaSourcesPublic.isEmpty()) {
       notifyListener();
@@ -1126,10 +1123,7 @@ public class ConcatenatingMediaSource extends CompositeMediaSource<MediaSourceHo
   private static final class DummyMediaSource extends BaseMediaSource {
 
     @Override
-    protected void prepareSourceInternal(
-        ExoPlayer player,
-        boolean isTopLevelSource,
-        @Nullable TransferListener mediaTransferListener) {
+    protected void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
       // Do nothing.
     }
 

library/core/src/main/java/com/google/android/exoplayer2/source/ExtractorMediaSource.java

@@ -19,7 +19,6 @@ import android.net.Uri;
 import android.os.Handler;
 import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.Player;
 import com.google.android.exoplayer2.extractor.DefaultExtractorsFactory;
 import com.google.android.exoplayer2.extractor.Extractor;
@@ -365,10 +364,7 @@ public final class ExtractorMediaSource extends BaseMediaSource
   }
 
   @Override
-  public void prepareSourceInternal(
-      ExoPlayer player,
-      boolean isTopLevelSource,
-      @Nullable TransferListener mediaTransferListener) {
+  public void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
     transferListener = mediaTransferListener;
     notifySourceInfoRefreshed(timelineDurationUs, /* isSeekable= */ false);
   }

library/core/src/main/java/com/google/android/exoplayer2/source/LoopingMediaSource.java

@@ -71,11 +71,8 @@ public final class LoopingMediaSource extends CompositeMediaSource<Void> {
   }
 
   @Override
-  public void prepareSourceInternal(
-      ExoPlayer player,
-      boolean isTopLevelSource,
-      @Nullable TransferListener mediaTransferListener) {
-    super.prepareSourceInternal(player, isTopLevelSource, mediaTransferListener);
+  public void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
+    super.prepareSourceInternal(mediaTransferListener);
     prepareChildSource(/* id= */ null, childSource);
   }
 

library/core/src/main/java/com/google/android/exoplayer2/source/MediaSource.java

@@ -18,30 +18,30 @@ package com.google.android.exoplayer2.source;
 import android.os.Handler;
 import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.upstream.Allocator;
 import com.google.android.exoplayer2.upstream.TransferListener;
 import java.io.IOException;
 
 /**
- * Defines and provides media to be played by an {@link ExoPlayer}. A MediaSource has two main
- * responsibilities:
+ * Defines and provides media to be played by an {@link com.google.android.exoplayer2.ExoPlayer}. A
+ * MediaSource has two main responsibilities:
  *
  * <ul>
  *   <li>To provide the player with a {@link Timeline} defining the structure of its media, and to
  *       provide a new timeline whenever the structure of the media changes. The MediaSource
  *       provides these timelines by calling {@link SourceInfoRefreshListener#onSourceInfoRefreshed}
- *       on the {@link SourceInfoRefreshListener}s passed to {@link #prepareSource(ExoPlayer,
- *       boolean, SourceInfoRefreshListener, TransferListener)}.
+ *       on the {@link SourceInfoRefreshListener}s passed to {@link
+ *       #prepareSource(SourceInfoRefreshListener, TransferListener)}.
  *   <li>To provide {@link MediaPeriod} instances for the periods in its timeline. MediaPeriods are
  *       obtained by calling {@link #createPeriod(MediaPeriodId, Allocator)}, and provide a way for
  *       the player to load and read the media.
  * </ul>
  *
  * All methods are called on the player's internal playback thread, as described in the {@link
- * ExoPlayer} Javadoc. They should not be called directly from application code. Instances can be
- * re-used, but only for one {@link ExoPlayer} instance simultaneously.
+ * com.google.android.exoplayer2.ExoPlayer} Javadoc. They should not be called directly from
+ * application code. Instances can be re-used, but only for one {@link
+ * com.google.android.exoplayer2.ExoPlayer} instance simultaneously.
  */
 public interface MediaSource {
 
@@ -236,11 +236,6 @@ public interface MediaSource {
    * <p>For each call to this method, a call to {@link #releaseSource(SourceInfoRefreshListener)} is
    * needed to remove the listener and to release the source if no longer required.
    *
-   * @param player The player for which this source is being prepared.
-   * @param isTopLevelSource Whether this source has been passed directly to {@link
-   *     ExoPlayer#prepare(MediaSource)} or {@link ExoPlayer#prepare(MediaSource, boolean,
-   *     boolean)}. If {@code false}, this source is being prepared by another source (e.g. {@link
-   *     ConcatenatingMediaSource}) for composition.
    * @param listener The listener to be added.
    * @param mediaTransferListener The transfer listener which should be informed of any media data
    *     transfers. May be null if no listener is available. Note that this listener should be only
@@ -248,8 +243,6 @@ public interface MediaSource {
    *     and other data.
    */
   void prepareSource(
-      ExoPlayer player,
-      boolean isTopLevelSource,
       SourceInfoRefreshListener listener,
       @Nullable TransferListener mediaTransferListener);
 

library/core/src/main/java/com/google/android/exoplayer2/source/MergingMediaSource.java

@@ -17,7 +17,6 @@ package com.google.android.exoplayer2.source;
 
 import android.support.annotation.IntDef;
 import android.support.annotation.Nullable;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.upstream.Allocator;
 import com.google.android.exoplayer2.upstream.TransferListener;
@@ -105,11 +104,8 @@ public final class MergingMediaSource extends CompositeMediaSource<Integer> {
   }
 
   @Override
-  public void prepareSourceInternal(
-      ExoPlayer player,
-      boolean isTopLevelSource,
-      @Nullable TransferListener mediaTransferListener) {
-    super.prepareSourceInternal(player, isTopLevelSource, mediaTransferListener);
+  public void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
+    super.prepareSourceInternal(mediaTransferListener);
     for (int i = 0; i < mediaSources.length; i++) {
       prepareChildSource(i, mediaSources[i]);
     }

library/core/src/main/java/com/google/android/exoplayer2/source/SingleSampleMediaSource.java

@@ -18,7 +18,6 @@ package com.google.android.exoplayer2.source;
 import android.net.Uri;
 import android.os.Handler;
 import android.support.annotation.Nullable;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.upstream.Allocator;
@@ -303,10 +302,7 @@ public final class SingleSampleMediaSource extends BaseMediaSource {
   }
 
   @Override
-  public void prepareSourceInternal(
-      ExoPlayer player,
-      boolean isTopLevelSource,
-      @Nullable TransferListener mediaTransferListener) {
+  public void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
     transferListener = mediaTransferListener;
     refreshSourceInfo(timeline, /* manifest= */ null);
   }

library/core/src/main/java/com/google/android/exoplayer2/source/ads/AdsMediaSource.java

@@ -22,7 +22,6 @@ import android.support.annotation.IntDef;
 import android.support.annotation.Nullable;
 import android.view.ViewGroup;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.source.CompositeMediaSource;
 import com.google.android.exoplayer2.source.DeferredMediaPeriod;
@@ -326,12 +325,9 @@ public final class AdsMediaSource extends CompositeMediaSource<MediaPeriodId> {
   }
 
   @Override
-  public void prepareSourceInternal(
-      final ExoPlayer player,
-      boolean isTopLevelSource,
-      @Nullable TransferListener mediaTransferListener) {
-    super.prepareSourceInternal(player, isTopLevelSource, mediaTransferListener);
-    final ComponentListener componentListener = new ComponentListener();
+  public void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
+    super.prepareSourceInternal(mediaTransferListener);
+    ComponentListener componentListener = new ComponentListener();
     this.componentListener = componentListener;
     prepareChildSource(DUMMY_CONTENT_MEDIA_PERIOD_ID, contentMediaSource);
     mainHandler.post(() -> adsLoader.start(componentListener, adUiViewGroup));

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

@@ -267,10 +267,8 @@ public final class ExoPlayerTest {
         new FakeMediaSource(timeline, new Object(), Builder.VIDEO_FORMAT) {
           @Override
           public synchronized void prepareSourceInternal(
-              ExoPlayer player,
-              boolean isTopLevelSource,
               @Nullable TransferListener mediaTransferListener) {
-            super.prepareSourceInternal(player, isTopLevelSource, mediaTransferListener);
+            super.prepareSourceInternal(mediaTransferListener);
             // We've queued a source info refresh on the playback thread's event queue. Allow the
             // test thread to prepare the player with the third source, and block this thread (the
             // playback thread) until the test thread's call to prepare() has returned.

library/dash/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaSource.java

@@ -22,7 +22,6 @@ import android.support.annotation.Nullable;
 import android.text.TextUtils;
 import android.util.SparseArray;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.ExoPlayerLibraryInfo;
 import com.google.android.exoplayer2.ParserException;
 import com.google.android.exoplayer2.Timeline;
@@ -637,10 +636,7 @@ public final class DashMediaSource extends BaseMediaSource {
   }
 
   @Override
-  public void prepareSourceInternal(
-      ExoPlayer player,
-      boolean isTopLevelSource,
-      @Nullable TransferListener mediaTransferListener) {
+  public void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
     this.mediaTransferListener = mediaTransferListener;
     if (sideloadedManifest) {
       processManifest(false);

library/hls/src/main/java/com/google/android/exoplayer2/source/hls/HlsMediaSource.java

@@ -19,7 +19,6 @@ import android.net.Uri;
 import android.os.Handler;
 import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.ExoPlayerLibraryInfo;
 import com.google.android.exoplayer2.extractor.Extractor;
 import com.google.android.exoplayer2.offline.StreamKey;
@@ -417,10 +416,7 @@ public final class HlsMediaSource extends BaseMediaSource
   }
 
   @Override
-  public void prepareSourceInternal(
-      ExoPlayer player,
-      boolean isTopLevelSource,
-      @Nullable TransferListener mediaTransferListener) {
+  public void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
     this.mediaTransferListener = mediaTransferListener;
     EventDispatcher eventDispatcher = createEventDispatcher(/* mediaPeriodId= */ null);
     playlistTracker.start(manifestUri, eventDispatcher, /* listener= */ this);

library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/SsMediaSource.java

@@ -20,7 +20,6 @@ import android.os.Handler;
 import android.os.SystemClock;
 import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.ExoPlayerLibraryInfo;
 import com.google.android.exoplayer2.ParserException;
 import com.google.android.exoplayer2.Timeline;
@@ -533,10 +532,7 @@ public final class SsMediaSource extends BaseMediaSource
   }
 
   @Override
-  public void prepareSourceInternal(
-      ExoPlayer player,
-      boolean isTopLevelSource,
-      @Nullable TransferListener mediaTransferListener) {
+  public void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
     this.mediaTransferListener = mediaTransferListener;
     if (sideloadedManifest) {
       manifestLoaderErrorThrower = new LoaderErrorThrower.Dummy();

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

@@ -22,7 +22,6 @@ import android.os.Handler;
 import android.os.SystemClock;
 import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.Timeline.Period;
@@ -96,10 +95,7 @@ public class FakeMediaSource extends BaseMediaSource {
   }
 
   @Override
-  public synchronized void prepareSourceInternal(
-      ExoPlayer player,
-      boolean isTopLevelSource,
-      @Nullable TransferListener mediaTransferListener) {
+  public synchronized void prepareSourceInternal(@Nullable TransferListener mediaTransferListener) {
     assertThat(preparedSource).isFalse();
     transferListener = mediaTransferListener;
     preparedSource = true;

testutils_robolectric/src/main/java/com/google/android/exoplayer2/testutil/MediaSourceTestRunner.java

@@ -17,17 +17,13 @@ package com.google.android.exoplayer2.testutil;
 
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.common.truth.Truth.assertWithMessage;
-import static org.junit.Assert.fail;
 
 import android.os.ConditionVariable;
 import android.os.Handler;
 import android.os.HandlerThread;
 import android.os.Looper;
-import android.os.Message;
 import android.support.annotation.Nullable;
 import android.util.Pair;
-import com.google.android.exoplayer2.ExoPlaybackException;
-import com.google.android.exoplayer2.PlayerMessage;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.source.MediaPeriod;
 import com.google.android.exoplayer2.source.MediaSource;
@@ -54,7 +50,6 @@ public class MediaSourceTestRunner {
 
   public static final int TIMEOUT_MS = 10000;
 
-  private final StubExoPlayer player;
   private final MediaSource mediaSource;
   private final MediaSourceListener mediaSourceListener;
   private final HandlerThread playbackThread;
@@ -79,7 +74,6 @@ public class MediaSourceTestRunner {
     playbackThread.start();
     Looper playbackLooper = playbackThread.getLooper();
     playbackHandler = new Handler(playbackLooper);
-    player = new EventHandlingExoPlayer(playbackLooper);
     mediaSourceListener = new MediaSourceListener();
     timelines = new LinkedBlockingDeque<>();
     completedLoads = new CopyOnWriteArrayList<>();
@@ -121,11 +115,7 @@ public class MediaSourceTestRunner {
     final IOException[] prepareError = new IOException[1];
     runOnPlaybackThread(
         () -> {
-          mediaSource.prepareSource(
-              player,
-              /* isTopLevelSource= */ true,
-              mediaSourceListener,
-              /* mediaTransferListener= */ null);
+          mediaSource.prepareSource(mediaSourceListener, /* mediaTransferListener= */ null);
           try {
             // TODO: This only catches errors that are set synchronously in prepareSource. To
             // capture async errors we'll need to poll maybeThrowSourceInfoRefreshError until the
@@ -417,43 +407,4 @@ public class MediaSourceTestRunner {
       Assertions.checkState(Looper.myLooper() == playbackThread.getLooper());
     }
   }
-
-  private static class EventHandlingExoPlayer extends StubExoPlayer
-      implements Handler.Callback, PlayerMessage.Sender {
-
-    private final Handler handler;
-
-    public EventHandlingExoPlayer(Looper looper) {
-      this.handler = new Handler(looper, this);
-    }
-
-    @Override
-    public Looper getApplicationLooper() {
-      return handler.getLooper();
-    }
-
-    @Override
-    public PlayerMessage createMessage(PlayerMessage.Target target) {
-      return new PlayerMessage(
-          /* sender= */ this, target, Timeline.EMPTY, /* defaultWindowIndex= */ 0, handler);
-    }
-
-    @Override
-    public void sendMessage(PlayerMessage message) {
-      handler.obtainMessage(0, message).sendToTarget();
-    }
-
-    @Override
-    @SuppressWarnings("unchecked")
-    public boolean handleMessage(Message msg) {
-      PlayerMessage message = (PlayerMessage) msg.obj;
-      try {
-        message.getTarget().handleMessage(message.getType(), message.getPayload());
-        message.markAsProcessed(/* isDelivered= */ true);
-      } catch (ExoPlaybackException e) {
-        fail("Unexpected ExoPlaybackException.");
-      }
-      return true;
-    }
-  }
 }