Allow delivery to multiple messages in a single message.

Where multiple messages are required to be sent in order
to perform a player reconfiguration, it will usually be
desirable to process all messages in a single "transaction"
(i.e. without any rendering happening when only some of
the messages have been applied).
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=123228334

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

@@ -104,8 +104,9 @@ public class VpxPlaybackTest extends InstrumentationTestCase {
               false),
           new DefaultAllocator(BUFFER_SEGMENT_SIZE), BUFFER_SEGMENT_SIZE * BUFFER_SEGMENT_COUNT,
           new Extractor[] {new MatroskaExtractor()});
-      player.sendMessage(videoRenderer, LibvpxVideoTrackRenderer.MSG_SET_OUTPUT_BUFFER_RENDERER,
+      player.sendMessages(new ExoPlayer.ExoPlayerMessage(videoRenderer,
-          new VpxVideoSurfaceView(context));
+          LibvpxVideoTrackRenderer.MSG_SET_OUTPUT_BUFFER_RENDERER,
+          new VpxVideoSurfaceView(context)));
       player.setSource(sampleSource);
       player.setPlayWhenReady(true);
       Looper.loop();

extensions/vp9/src/main/java/com/google/android/exoplayer/ext/vp9/LibvpxVideoTrackRenderer.java

@@ -41,10 +41,10 @@ public final class LibvpxVideoTrackRenderer extends TrackRenderer {
 
   /**
    * The type of a message that can be passed to an instance of this class via
-   * {@link ExoPlayer#sendMessage} or {@link ExoPlayer#blockingSendMessage}. The message object
+   * {@link ExoPlayer#sendMessages} or {@link ExoPlayer#blockingSendMessages}. The message object
    * should be the target {@link VpxOutputBufferRenderer}, or null.
    */
-  public static final int MSG_SET_OUTPUT_BUFFER_RENDERER = 2;
+  public static final int MSG_SET_OUTPUT_BUFFER_RENDERER = C.MSG_CUSTOM_BASE;
 
   /**
    * The number of input buffers and the number of output buffers. The track renderer may limit the

library/src/main/java/com/google/android/exoplayer/C.java

@@ -231,25 +231,30 @@ public interface C {
 
   /**
    * The type of a message that can be passed to a video {@link TrackRenderer} via
-   * {@link ExoPlayer#sendMessage} or {@link ExoPlayer#blockingSendMessage}. The message object
+   * {@link ExoPlayer#sendMessages} or {@link ExoPlayer#blockingSendMessages}. The message object
    * should be the target {@link Surface}, or null.
    */
   int MSG_SET_SURFACE = 1;
 
   /**
    * The type of a message that can be passed to an audio {@link TrackRenderer} via
-   * {@link ExoPlayer#sendMessage} or {@link ExoPlayer#blockingSendMessage}. The message object
+   * {@link ExoPlayer#sendMessages} or {@link ExoPlayer#blockingSendMessages}. The message object
    * should be a {@link Float} with 0 being silence and 1 being unity gain.
    */
   int MSG_SET_VOLUME = 2;
 
   /**
    * The type of a message that can be passed to an audio {@link TrackRenderer} via
-   * {@link ExoPlayer#sendMessage} or {@link ExoPlayer#blockingSendMessage}. The message object
+   * {@link ExoPlayer#sendMessages} or {@link ExoPlayer#blockingSendMessages}. The message object
    * should be a {@link android.media.PlaybackParams}, which will be used to configure the
    * underlying {@link android.media.AudioTrack}. The message object should not be modified by the
    * caller after it has been passed
    */
   int MSG_SET_PLAYBACK_PARAMS = 3;
 
+  /**
+   * A minimum value for custom {@link TrackRenderer} message types.
+   */
+  int MSG_CUSTOM_BASE = 10000;
+
 }

library/src/main/java/com/google/android/exoplayer/ExoPlayer.java

@@ -132,8 +132,8 @@ public interface ExoPlayer {
   /**
    * A component of an {@link ExoPlayer} that can receive messages on the playback thread.
    * <p>
-   * Messages can be delivered to a component via {@link ExoPlayer#sendMessage} and
+   * Messages can be delivered to a component via {@link ExoPlayer#sendMessages} and
-   * {@link ExoPlayer#blockingSendMessage}.
+   * {@link ExoPlayer#blockingSendMessages}.
    */
   interface ExoPlayerComponent {
 
@@ -148,6 +148,28 @@ public interface ExoPlayer {
 
   }
 
+  /**
+   * Defines a message and a target {@link ExoPlayerComponent} to receive it.
+   */
+  final class ExoPlayerMessage {
+
+    public final ExoPlayerComponent target;
+    public final int messageType;
+    public final Object message;
+
+    /**
+     * @param target The target of the message.
+     * @param messageType An integer identifying the type of message.
+     * @param message The message object.
+     */
+    public ExoPlayerMessage(ExoPlayerComponent target, int messageType, Object message) {
+      this.target = target;
+      this.messageType = messageType;
+      this.message = message;
+    }
+
+  }
+
   /**
    * The player does not have a source to load, so it is neither buffering nor ready to play.
    */
@@ -256,25 +278,21 @@ public interface ExoPlayer {
   void release();
 
   /**
-   * Sends a message to a specified component. The message is delivered to the component on the
+   * Sends messages to their target components. The messages are delivered on the playback thread.
-   * playback thread. If the component throws a {@link ExoPlaybackException}, then it is
+   * If a component throws an {@link ExoPlaybackException} then it is propagated out of the player
-   * propagated out of the player as an error.
+   * as an error.
    *
-   * @param target The target to which the message should be delivered.
+   * @param messages The messages to be sent.
-   * @param messageType An integer that can be used to identify the type of the message.
-   * @param message The message object.
    */
-  void sendMessage(ExoPlayerComponent target, int messageType, Object message);
+  void sendMessages(ExoPlayerMessage... messages);
 
   /**
-   * Blocking variant of {@link #sendMessage(ExoPlayerComponent, int, Object)} that does not return
+   * Variant of {@link #sendMessages(ExoPlayerMessage...)} that blocks until after the messages have
-   * until after the message has been delivered.
+   * been delivered.
    *
-   * @param target The target to which the message should be delivered.
+   * @param messages The messages to be sent.
-   * @param messageType An integer that can be used to identify the type of the message.
-   * @param message The message object.
    */
-  void blockingSendMessage(ExoPlayerComponent target, int messageType, Object message);
+  void blockingSendMessages(ExoPlayerMessage... messages);
 
   /**
    * Gets the duration of the track in milliseconds.

library/src/main/java/com/google/android/exoplayer/ExoPlayerImpl.java

@@ -129,13 +129,13 @@ import java.util.concurrent.CopyOnWriteArraySet;
   }
 
   @Override
-  public void sendMessage(ExoPlayerComponent target, int messageType, Object message) {
+  public void sendMessages(ExoPlayerMessage... messages) {
-    internalPlayer.sendMessage(target, messageType, message);
+    internalPlayer.sendMessages(messages);
   }
 
   @Override
-  public void blockingSendMessage(ExoPlayerComponent target, int messageType, Object message) {
+  public void blockingSendMessages(ExoPlayerMessage... messages) {
-    internalPlayer.blockingSendMessage(target, messageType, message);
+    internalPlayer.blockingSendMessages(messages);
   }
 
   @Override

library/src/main/java/com/google/android/exoplayer/ExoPlayerImplInternal.java

@@ -15,7 +15,7 @@
  */
 package com.google.android.exoplayer;
 
-import com.google.android.exoplayer.ExoPlayer.ExoPlayerComponent;
+import com.google.android.exoplayer.ExoPlayer.ExoPlayerMessage;
 import com.google.android.exoplayer.TrackSelector.InvalidationListener;
 import com.google.android.exoplayer.util.PriorityHandlerThread;
 import com.google.android.exoplayer.util.TraceUtil;
@@ -154,19 +154,22 @@ import java.util.concurrent.atomic.AtomicInteger;
     handler.sendEmptyMessage(MSG_STOP);
   }
 
-  public void sendMessage(ExoPlayerComponent target, int messageType, Object message) {
+  public void sendMessages(ExoPlayerMessage... messages) {
+    if (released) {
+      Log.w(TAG, "Ignoring messages sent after release.");
+      return;
+    }
     customMessagesSent++;
-    handler.obtainMessage(MSG_CUSTOM, messageType, 0, Pair.create(target, message)).sendToTarget();
+    handler.obtainMessage(MSG_CUSTOM, messages).sendToTarget();
   }
 
-  public synchronized void blockingSendMessage(ExoPlayerComponent target, int messageType,
+  public synchronized void blockingSendMessages(ExoPlayerMessage... messages) {
-      Object message) {
     if (released) {
-      Log.w(TAG, "Sent message(" + messageType + ") after release. Message ignored.");
+      Log.w(TAG, "Ignoring messages sent after release.");
       return;
     }
     int messageNumber = customMessagesSent++;
-    handler.obtainMessage(MSG_CUSTOM, messageType, 0, Pair.create(target, message)).sendToTarget();
+    handler.obtainMessage(MSG_CUSTOM, messages).sendToTarget();
     while (customMessagesProcessed <= messageNumber) {
       try {
         wait();
@@ -225,7 +228,7 @@ import java.util.concurrent.atomic.AtomicInteger;
           return true;
         }
         case MSG_CUSTOM: {
-          sendMessageInternal(msg.arg1, msg.obj);
+          sendMessagesInternal((ExoPlayerMessage[]) msg.obj);
           return true;
         }
         case MSG_TRACK_SELECTION_INVALIDATED: {
@@ -517,12 +520,11 @@ import java.util.concurrent.atomic.AtomicInteger;
     }
   }
 
-  private <T> void sendMessageInternal(int what, Object obj)
+  private void sendMessagesInternal(ExoPlayerMessage[] messages) throws ExoPlaybackException {
-      throws ExoPlaybackException {
     try {
-      @SuppressWarnings("unchecked")
+      for (ExoPlayerMessage message : messages) {
-      Pair<ExoPlayerComponent, Object> targetAndMessage = (Pair<ExoPlayerComponent, Object>) obj;
+        message.target.handleMessage(message.messageType, message.message);
-      targetAndMessage.first.handleMessage(what, targetAndMessage.second);
+      }
       if (preparedSource) {
         // The message may have caused something to change that now requires us to do work.
         handler.sendEmptyMessage(MSG_DO_SOME_WORK);

library/src/main/java/com/google/android/exoplayer/SimpleExoPlayer.java

@@ -89,6 +89,8 @@ public final class SimpleExoPlayer implements ExoPlayer {
   private final TrackRenderer[] renderers;
   private final ComponentListener componentListener;
   private final Handler mainHandler;
+  private final int videoRendererCount;
+  private final int audioRendererCount;
 
   private Format videoFormat;
   private Format audioFormat;
@@ -115,6 +117,22 @@ public final class SimpleExoPlayer implements ExoPlayer {
     buildRenderers(context, drmSessionManager, renderersList);
     renderers = renderersList.toArray(new TrackRenderer[renderersList.size()]);
 
+    // Obtain counts of video and audio renderers.
+    int videoRendererCount = 0;
+    int audioRendererCount = 0;
+    for (TrackRenderer renderer : renderers) {
+      switch (renderer.getTrackType()) {
+        case C.TRACK_TYPE_VIDEO:
+          videoRendererCount++;
+          break;
+        case C.TRACK_TYPE_AUDIO:
+          audioRendererCount++;
+          break;
+      }
+    }
+    this.videoRendererCount = videoRendererCount;
+    this.audioRendererCount = audioRendererCount;
+
     // Build the player and associated objects.
     player = new ExoPlayerImpl(renderers, trackSelector, minBufferMs, minRebufferMs);
   }
@@ -145,15 +163,18 @@ public final class SimpleExoPlayer implements ExoPlayer {
    * @param surface The {@link Surface}.
    */
   public void setSurface(Surface surface) {
+    ExoPlayerMessage[] messages = new ExoPlayerMessage[videoRendererCount];
+    int count = 0;
     for (TrackRenderer renderer : renderers) {
       if (renderer.getTrackType() == C.TRACK_TYPE_VIDEO) {
+        messages[count++] = new ExoPlayerMessage(renderer, C.MSG_SET_SURFACE, surface);
+      }
+    }
     if (surface == null) {
       // Block to ensure that the surface is not accessed after the method returns.
-          player.blockingSendMessage(renderer, C.MSG_SET_SURFACE, null);
+      player.blockingSendMessages(messages);
     } else {
-          player.sendMessage(renderer, C.MSG_SET_SURFACE, surface);
+      player.sendMessages(messages);
-        }
-      }
     }
   }
 
@@ -163,11 +184,14 @@ public final class SimpleExoPlayer implements ExoPlayer {
    * @param volume The volume.
    */
   public void setVolume(float volume) {
+    ExoPlayerMessage[] messages = new ExoPlayerMessage[audioRendererCount];
+    int count = 0;
     for (TrackRenderer renderer : renderers) {
       if (renderer.getTrackType() == C.TRACK_TYPE_AUDIO) {
-        player.sendMessage(renderer, C.MSG_SET_VOLUME, volume);
+        messages[count++] = new ExoPlayerMessage(renderer, C.MSG_SET_VOLUME, volume);
       }
     }
+    player.sendMessages(messages);
   }
 
   /**
@@ -296,13 +320,13 @@ public final class SimpleExoPlayer implements ExoPlayer {
   }
 
   @Override
-  public void sendMessage(ExoPlayerComponent target, int messageType, Object message) {
+  public void sendMessages(ExoPlayerMessage... messages) {
-    player.sendMessage(target, messageType, message);
+    player.sendMessages(messages);
   }
 
   @Override
-  public void blockingSendMessage(ExoPlayerComponent target, int messageType, Object message) {
+  public void blockingSendMessages(ExoPlayerMessage... messages) {
-    player.blockingSendMessage(target, messageType, message);
+    player.blockingSendMessages(messages);
   }
 
   @Override