Add TrackSelectorResult

This class can accommodate extra information that may potentially
be specified by TrackSelectors in the future (e.g. configuration
for renderers). Even if we don't do this, it's cleaner to have a
proper class and an info field to refer to, as opposed to using a
Pair.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=144428963

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

@@ -22,12 +22,12 @@ import android.os.Message;
 import android.util.Log;
 import com.google.android.exoplayer2.ExoPlayerImplInternal.PlaybackInfo;
 import com.google.android.exoplayer2.ExoPlayerImplInternal.SourceInfo;
-import com.google.android.exoplayer2.ExoPlayerImplInternal.TrackInfo;
 import com.google.android.exoplayer2.source.MediaSource;
 import com.google.android.exoplayer2.source.TrackGroupArray;
 import com.google.android.exoplayer2.trackselection.TrackSelection;
 import com.google.android.exoplayer2.trackselection.TrackSelectionArray;
 import com.google.android.exoplayer2.trackselection.TrackSelector;
+import com.google.android.exoplayer2.trackselection.TrackSelectorResult;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.Util;
 import java.util.concurrent.CopyOnWriteArraySet;
@@ -319,11 +319,11 @@ import java.util.concurrent.CopyOnWriteArraySet;
         break;
       }
       case ExoPlayerImplInternal.MSG_TRACKS_CHANGED: {
-        TrackInfo trackInfo = (TrackInfo) msg.obj;
+        TrackSelectorResult trackSelectorResult = (TrackSelectorResult) msg.obj;
         tracksSelected = true;
-        trackGroups = trackInfo.groups;
-        trackSelections = trackInfo.selections;
-        trackSelector.onSelectionActivated(trackInfo.info);
+        trackGroups = trackSelectorResult.groups;
+        trackSelections = trackSelectorResult.selections;
+        trackSelector.onSelectionActivated(trackSelectorResult.info);
         for (EventListener listener : listeners) {
           listener.onTracksChanged(trackGroups, trackSelections);
         }

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

@@ -26,10 +26,10 @@ import com.google.android.exoplayer2.ExoPlayer.ExoPlayerMessage;
 import com.google.android.exoplayer2.source.MediaPeriod;
 import com.google.android.exoplayer2.source.MediaSource;
 import com.google.android.exoplayer2.source.SampleStream;
-import com.google.android.exoplayer2.source.TrackGroupArray;
 import com.google.android.exoplayer2.trackselection.TrackSelection;
 import com.google.android.exoplayer2.trackselection.TrackSelectionArray;
 import com.google.android.exoplayer2.trackselection.TrackSelector;
+import com.google.android.exoplayer2.trackselection.TrackSelectorResult;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.MediaClock;
 import com.google.android.exoplayer2.util.PriorityHandlerThread;
@@ -72,20 +72,6 @@ import java.io.IOException;
 
   }
 
-  public static final class TrackInfo {
-
-    public final TrackGroupArray groups;
-    public final TrackSelectionArray selections;
-    public final Object info;
-
-    public TrackInfo(TrackGroupArray groups, TrackSelectionArray selections, Object info) {
-      this.groups = groups;
-      this.selections = selections;
-      this.info = info;
-    }
-
-  }
-
   public static final class SourceInfo {
 
     public final Timeline timeline;
@@ -799,7 +785,8 @@ import java.io.IOException;
           }
         }
       }
-      eventHandler.obtainMessage(MSG_TRACKS_CHANGED, periodHolder.getTrackInfo()).sendToTarget();
+      eventHandler.obtainMessage(MSG_TRACKS_CHANGED, periodHolder.trackSelectorResult)
+          .sendToTarget();
       enableRenderers(rendererWasEnabledFlags, enabledRendererCount);
     } else {
       // Release and re-prepare/buffer periods after the one whose selection changed.
@@ -1161,9 +1148,9 @@ import java.io.IOException;
     }
 
     if (readingPeriodHolder.next != null && readingPeriodHolder.next.prepared) {
-      TrackSelectionArray oldTrackSelections = readingPeriodHolder.trackSelections;
+      TrackSelectionArray oldTrackSelections = readingPeriodHolder.trackSelectorResult.selections;
       readingPeriodHolder = readingPeriodHolder.next;
-      TrackSelectionArray newTrackSelections = readingPeriodHolder.trackSelections;
+      TrackSelectionArray newTrackSelections = readingPeriodHolder.trackSelectorResult.selections;
 
       boolean initialDiscontinuity =
           readingPeriodHolder.mediaPeriod.readDiscontinuity() != C.TIME_UNSET;
@@ -1330,7 +1317,7 @@ import java.io.IOException;
     for (int i = 0; i < renderers.length; i++) {
       Renderer renderer = renderers[i];
       rendererWasEnabledFlags[i] = renderer.getState() != Renderer.STATE_DISABLED;
-      TrackSelection newSelection = periodHolder.trackSelections.get(i);
+      TrackSelection newSelection = periodHolder.trackSelectorResult.selections.get(i);
       if (newSelection != null) {
         enabledRendererCount++;
       }
@@ -1352,7 +1339,7 @@ import java.io.IOException;
     }
 
     playingPeriodHolder = periodHolder;
-    eventHandler.obtainMessage(MSG_TRACKS_CHANGED, periodHolder.getTrackInfo()).sendToTarget();
+    eventHandler.obtainMessage(MSG_TRACKS_CHANGED, periodHolder.trackSelectorResult).sendToTarget();
     enableRenderers(rendererWasEnabledFlags, enabledRendererCount);
   }
 
@@ -1362,7 +1349,7 @@ import java.io.IOException;
     enabledRendererCount = 0;
     for (int i = 0; i < renderers.length; i++) {
       Renderer renderer = renderers[i];
-      TrackSelection newSelection = playingPeriodHolder.trackSelections.get(i);
+      TrackSelection newSelection = playingPeriodHolder.trackSelectorResult.selections.get(i);
       if (newSelection != null) {
         enabledRenderers[enabledRendererCount++] = renderer;
         if (renderer.getState() == Renderer.STATE_DISABLED) {
@@ -1414,6 +1401,7 @@ import java.io.IOException;
     public boolean hasEnabledTracks;
     public MediaPeriodHolder next;
     public boolean needsContinueLoading;
+    public TrackSelectorResult trackSelectorResult;
 
     private final Renderer[] renderers;
     private final RendererCapabilities[] rendererCapabilities;
@@ -1421,9 +1409,6 @@ import java.io.IOException;
     private final LoadControl loadControl;
     private final MediaSource mediaSource;
 
-    private Object trackSelectionsInfo;
-    private TrackGroupArray trackGroups;
-    private TrackSelectionArray trackSelections;
     private TrackSelectionArray periodTrackSelections;
 
     public MediaPeriodHolder(Renderer[] renderers, RendererCapabilities[] rendererCapabilities,
@@ -1470,20 +1455,18 @@ import java.io.IOException;
 
     public void handlePrepared() throws ExoPlaybackException {
       prepared = true;
-      trackGroups = mediaPeriod.getTrackGroups();
       selectTracks();
       startPositionUs = updatePeriodTrackSelection(startPositionUs, false);
     }
 
     public boolean selectTracks() throws ExoPlaybackException {
-      Pair<TrackSelectionArray, Object> selectorResult = trackSelector.selectTracks(
-          rendererCapabilities, trackGroups);
-      TrackSelectionArray newTrackSelections = selectorResult.first;
+      TrackSelectorResult selectorResult = trackSelector.selectTracks(rendererCapabilities,
+          mediaPeriod.getTrackGroups());
+      TrackSelectionArray newTrackSelections = selectorResult.selections;
       if (newTrackSelections.equals(periodTrackSelections)) {
         return false;
       }
-      trackSelections = newTrackSelections;
-      trackSelectionsInfo = selectorResult.second;
+      trackSelectorResult = selectorResult;
       return true;
     }
 
@@ -1494,6 +1477,7 @@ import java.io.IOException;
 
     public long updatePeriodTrackSelection(long positionUs, boolean forceRecreateStreams,
         boolean[] streamResetFlags) {
+      TrackSelectionArray trackSelections = trackSelectorResult.selections;
       for (int i = 0; i < trackSelections.length; i++) {
         mayRetainStreamFlags[i] = !forceRecreateStreams
             && Util.areEqual(periodTrackSelections == null ? null : periodTrackSelections.get(i),
@@ -1517,14 +1501,10 @@ import java.io.IOException;
       }
 
       // The track selection has changed.
-      loadControl.onTracksSelected(renderers, trackGroups, trackSelections);
+      loadControl.onTracksSelected(renderers, trackSelectorResult.groups, trackSelections);
       return positionUs;
     }
 
-    public TrackInfo getTrackInfo() {
-      return new TrackInfo(trackGroups, trackSelections, trackSelectionsInfo);
-    }
-
     public void release() {
       try {
         mediaSource.releasePeriod(mediaPeriod);

library/src/main/java/com/google/android/exoplayer2/audio/AudioTrack.java

@@ -876,6 +876,7 @@ public final class AudioTrack {
       framesPerEncodedSample = 0;
       currentSourceBuffer = null;
       avSyncHeader = null;
+      bytesUntilNextAvSync = 0;
       startMediaTimeState = START_NOT_SET;
       latencyUs = 0;
       resetSyncParams();

library/src/main/java/com/google/android/exoplayer2/trackselection/MappingTrackSelector.java

@@ -15,7 +15,6 @@
  */
 package com.google.android.exoplayer2.trackselection;
 
-import android.util.Pair;
 import android.util.SparseArray;
 import android.util.SparseBooleanArray;
 import com.google.android.exoplayer2.C;
@@ -227,9 +226,8 @@ public abstract class MappingTrackSelector extends TrackSelector {
   // TrackSelector implementation.
 
   @Override
-  public final Pair<TrackSelectionArray, Object> selectTracks(
-      RendererCapabilities[] rendererCapabilities, TrackGroupArray trackGroups)
-      throws ExoPlaybackException {
+  public final TrackSelectorResult selectTracks(RendererCapabilities[] rendererCapabilities,
+      TrackGroupArray trackGroups) throws ExoPlaybackException {
     // Structures into which data will be written during the selection. The extra item at the end
     // of each array is to store data associated with track groups that cannot be associated with
     // any renderer.
@@ -297,7 +295,7 @@ public abstract class MappingTrackSelector extends TrackSelector {
     MappedTrackInfo mappedTrackInfo = new MappedTrackInfo(rendererTrackTypes,
         rendererTrackGroupArrays, mixedMimeTypeAdaptationSupport, rendererFormatSupports,
         unassociatedTrackGroupArray);
-    return Pair.<TrackSelectionArray, Object>create(new TrackSelectionArray(trackSelections),
+    return new TrackSelectorResult(trackGroups, new TrackSelectionArray(trackSelections),
         mappedTrackInfo);
   }
 

library/src/main/java/com/google/android/exoplayer2/trackselection/TrackSelector.java

@@ -15,7 +15,6 @@
  */
 package com.google.android.exoplayer2.trackselection;
 
-import android.util.Pair;
 import com.google.android.exoplayer2.ExoPlaybackException;
 import com.google.android.exoplayer2.RendererCapabilities;
 import com.google.android.exoplayer2.source.TrackGroupArray;
@@ -47,25 +46,22 @@ public abstract class TrackSelector {
   }
 
   /**
-   * Generates {@link TrackSelectionArray} for the renderers.
+   * Performs a track selection for renderers.
    *
-   * @param rendererCapabilities The {@link RendererCapabilities} of the renderers for which
-   *     {@link TrackSelection}s are to be generated.
+   * @param rendererCapabilities The {@link RendererCapabilities} of the renderers for which tracks
+   *     are to be selected.
    * @param trackGroups The available track groups.
-   * @return The track selections, and an implementation specific object that will be returned to
-   *     the selector via {@link #onSelectionActivated(Object)} should the selections be activated.
+   * @return A {@link TrackSelectorResult} describing the track selections.
    * @throws ExoPlaybackException If an error occurs selecting tracks.
    */
-  public abstract Pair<TrackSelectionArray, Object> selectTracks(
-      RendererCapabilities[] rendererCapabilities, TrackGroupArray trackGroups)
-      throws ExoPlaybackException;
+  public abstract TrackSelectorResult selectTracks(RendererCapabilities[] rendererCapabilities,
+      TrackGroupArray trackGroups) throws ExoPlaybackException;
 
   /**
-   * Called when {@link TrackSelectionArray} previously generated by
-   * {@link #selectTracks(RendererCapabilities[], TrackGroupArray)} are activated.
+   * Called when a {@link TrackSelectorResult} previously generated by
+   * {@link #selectTracks(RendererCapabilities[], TrackGroupArray)} is activated.
    *
-   * @param info The information associated with the selections, or null if the selected tracks are
-   *     being cleared.
+   * @param info The value of {@link TrackSelectorResult#info} in the activated result.
    */
   public abstract void onSelectionActivated(Object info);
 

library/src/main/java/com/google/android/exoplayer2/trackselection/TrackSelectorResult.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.android.exoplayer2.trackselection;
+
+import com.google.android.exoplayer2.source.TrackGroupArray;
+
+/**
+ * The result of a {@link TrackSelector} operation.
+ */
+public final class TrackSelectorResult {
+
+  /**
+   * The groups provided to the {@link TrackSelector}.
+   */
+  public final TrackGroupArray groups;
+  /**
+   * A {@link TrackSelectionArray} containing the selection for each renderer.
+   */
+  public final TrackSelectionArray selections;
+  /**
+   * An opaque object that will be returned to {@link TrackSelector#onSelectionActivated(Object)}
+   * should the selections be activated.
+   */
+  public final Object info;
+
+  /**
+   * @param groups The groups provided to the {@link TrackSelector}.
+   * @param selections A {@link TrackSelectionArray} containing the selection for each renderer.
+   * @param info An opaque object that will be returned to
+   *     {@link TrackSelector#onSelectionActivated(Object)} should the selections be activated.
+   */
+  public TrackSelectorResult(TrackGroupArray groups, TrackSelectionArray selections, Object info) {
+    this.groups = groups;
+    this.selections = selections;
+    this.info = info;
+  }
+
+}