Add loading error reports to ExtractorSampleSource

This CL also implements loading errors in the DemoApp by logging them.
The sourceId in the ExtractorSampleSource interface allows a class to
implement the same signature for all the SampleSources. The
eventSourceId in the ExtractorSampleSource is unlikely to be useful,
considering it is expected to use one single source. However, it was
added for two reasons:

* Consistency, since the ChunkSampleSource
* In the strange case that two ExtractorSampleSources live at the same
  time, it would be possible to diferentiate them.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=116366928

demo/src/main/java/com/google/android/exoplayer/demo/player/DemoPlayer.java

@@ -31,6 +31,7 @@
 import com.google.android.exoplayer.chunk.Format;
 import com.google.android.exoplayer.dash.DashChunkSource;
 import com.google.android.exoplayer.drm.StreamingDrmSessionManager;
+import com.google.android.exoplayer.extractor.ExtractorSampleSource;
 import com.google.android.exoplayer.hls.HlsSampleSource;
 import com.google.android.exoplayer.metadata.MetadataTrackRenderer.MetadataRenderer;
 import com.google.android.exoplayer.metadata.id3.Id3Frame;
@@ -57,10 +58,11 @@
  * SmoothStreaming and so on).
  */
 public class DemoPlayer implements ExoPlayer.Listener, ChunkSampleSource.EventListener,
-    HlsSampleSource.EventListener, DefaultBandwidthMeter.EventListener,
-    MediaCodecVideoTrackRenderer.EventListener, MediaCodecAudioTrackRenderer.EventListener,
-    StreamingDrmSessionManager.EventListener, DashChunkSource.EventListener, TextRenderer,
-    MetadataRenderer<List<Id3Frame>>, DebugTextViewHelper.Provider {
+    HlsSampleSource.EventListener, ExtractorSampleSource.EventListener,
+    DefaultBandwidthMeter.EventListener, MediaCodecVideoTrackRenderer.EventListener,
+    MediaCodecAudioTrackRenderer.EventListener, StreamingDrmSessionManager.EventListener,
+    DashChunkSource.EventListener, TextRenderer, MetadataRenderer<List<Id3Frame>>,
+    DebugTextViewHelper.Provider {
 
   /**
    * Builds renderers for the player.

demo/src/main/java/com/google/android/exoplayer/demo/player/ExtractorRendererBuilder.java

@@ -34,6 +34,7 @@
 import android.media.AudioManager;
 import android.media.MediaCodec;
 import android.net.Uri;
+import android.os.Handler;
 
 /**
  * A {@link RendererBuilder} for streams that can be read using an {@link Extractor}.
@@ -56,21 +57,21 @@ public ExtractorRendererBuilder(Context context, String userAgent, Uri uri) {
   @Override
   public void buildRenderers(DemoPlayer player) {
     Allocator allocator = new DefaultAllocator(BUFFER_SEGMENT_SIZE);
+    Handler mainHandler = player.getMainHandler();
 
     // Build the video and audio renderers.
-    DefaultBandwidthMeter bandwidthMeter = new DefaultBandwidthMeter(player.getMainHandler(),
-        null);
+    DefaultBandwidthMeter bandwidthMeter = new DefaultBandwidthMeter(mainHandler, null);
     DataSource dataSource = new DefaultUriDataSource(context, bandwidthMeter, userAgent);
     ExtractorSampleSource sampleSource = new ExtractorSampleSource(uri, dataSource, allocator,
-        BUFFER_SEGMENT_COUNT * BUFFER_SEGMENT_SIZE);
+        BUFFER_SEGMENT_COUNT * BUFFER_SEGMENT_SIZE, mainHandler, player, 0);
     MediaCodecVideoTrackRenderer videoRenderer = new MediaCodecVideoTrackRenderer(context,
         sampleSource, MediaCodecSelector.DEFAULT, MediaCodec.VIDEO_SCALING_MODE_SCALE_TO_FIT, 5000,
-        player.getMainHandler(), player, 50);
+        mainHandler, player, 50);
     MediaCodecAudioTrackRenderer audioRenderer = new MediaCodecAudioTrackRenderer(sampleSource,
-        MediaCodecSelector.DEFAULT, null, true, player.getMainHandler(), player,
+        MediaCodecSelector.DEFAULT, null, true, mainHandler, player,
         AudioCapabilities.getCapabilities(context), AudioManager.STREAM_MUSIC);
     TrackRenderer textRenderer = new TextTrackRenderer(sampleSource, player,
-        player.getMainHandler().getLooper());
+        mainHandler.getLooper());
 
     // Invoke the callback.
     TrackRenderer[] renderers = new TrackRenderer[DemoPlayer.RENDERER_COUNT];

library/src/main/java/com/google/android/exoplayer/extractor/ExtractorSampleSource.java

@@ -33,6 +33,7 @@
 import com.google.android.exoplayer.util.Util;
 
 import android.net.Uri;
+import android.os.Handler;
 import android.os.SystemClock;
 import android.util.SparseArray;
 
@@ -69,6 +70,21 @@
 public final class ExtractorSampleSource implements SampleSource, SampleSourceReader,
     ExtractorOutput, Loader.Callback {
 
+  /**
+   * Interface definition for a callback to be notified of {@link ExtractorSampleSource} events.
+   */
+  public interface EventListener {
+
+    /**
+     * Invoked when an error occurs loading media data.
+     *
+     * @param sourceId The id of the reporting {@link SampleSource}.
+     * @param e The cause of the failure.
+     */
+    void onLoadError(int sourceId, IOException e);
+
+  }
+
   /**
    * Thrown if the input format could not recognized.
    */
@@ -176,6 +192,9 @@ public UnrecognizedInputFormatException(Extractor[] extractors) {
   private final int minLoadableRetryCount;
   private final Uri uri;
   private final DataSource dataSource;
+  private final Handler eventHandler;
+  private final EventListener eventListener;
+  private final int eventSourceId;
 
   private volatile boolean tracksBuilt;
   private volatile SeekMap seekMap;
@@ -224,6 +243,26 @@ public ExtractorSampleSource(Uri uri, DataSource dataSource, Allocator allocator
         extractors);
   }
 
+  /**
+   * @param uri The {@link Uri} of the media stream.
+   * @param dataSource A data source to read the media stream.
+   * @param allocator An {@link Allocator} from which to obtain memory allocations.
+   * @param requestedBufferSize The requested total buffer size for storing sample data, in bytes.
+   *     The actual allocated size may exceed the value passed in if the implementation requires it.
+   * @param eventHandler A handler to use when delivering events to {@code eventListener}. May be
+   *     null if delivery of events is not required.
+   * @param eventListener A listener of events. May be null if delivery of events is not required.
+   * @param eventSourceId An identifier that gets passed to {@code eventListener} methods.
+   * @param extractors {@link Extractor}s to extract the media stream, in order of decreasing
+   *     priority. If omitted, the default extractors will be used.
+   */
+  public ExtractorSampleSource(Uri uri, DataSource dataSource, Allocator allocator,
+      int requestedBufferSize, Handler eventHandler, EventListener eventListener,
+      int eventSourceId, Extractor... extractors) {
+    this(uri, dataSource, allocator, requestedBufferSize, MIN_RETRY_COUNT_DEFAULT_FOR_MEDIA,
+        eventHandler, eventListener, eventSourceId, extractors);
+  }
+
   /**
    * @param uri The {@link Uri} of the media stream.
    * @param dataSource A data source to read the media stream.
@@ -237,8 +276,33 @@ public ExtractorSampleSource(Uri uri, DataSource dataSource, Allocator allocator
    */
   public ExtractorSampleSource(Uri uri, DataSource dataSource, Allocator allocator,
       int requestedBufferSize, int minLoadableRetryCount, Extractor... extractors) {
+    this(uri, dataSource, allocator, requestedBufferSize, minLoadableRetryCount, null, null, 0,
+        extractors);
+  }
+
+  /**
+   * @param uri The {@link Uri} of the media stream.
+   * @param dataSource A data source to read the media stream.
+   * @param allocator An {@link Allocator} from which to obtain memory allocations.
+   * @param requestedBufferSize The requested total buffer size for storing sample data, in bytes.
+   *     The actual allocated size may exceed the value passed in if the implementation requires it.
+   * @param minLoadableRetryCount The minimum number of times that the sample source will retry
+   *     if a loading error occurs.
+   * @param eventHandler A handler to use when delivering events to {@code eventListener}. May be
+   *     null if delivery of events is not required.
+   * @param eventListener A listener of events. May be null if delivery of events is not required.
+   * @param eventSourceId An identifier that gets passed to {@code eventListener} methods.
+   * @param extractors {@link Extractor}s to extract the media stream, in order of decreasing
+   *     priority. If omitted, the default extractors will be used.
+   */
+  public ExtractorSampleSource(Uri uri, DataSource dataSource, Allocator allocator,
+      int requestedBufferSize, int minLoadableRetryCount, Handler eventHandler,
+      EventListener eventListener, int eventSourceId, Extractor... extractors) {
     this.uri = uri;
     this.dataSource = dataSource;
+    this.eventListener = eventListener;
+    this.eventHandler = eventHandler;
+    this.eventSourceId = eventSourceId;
     this.allocator = allocator;
     this.requestedBufferSize = requestedBufferSize;
     this.minLoadableRetryCount = minLoadableRetryCount;
@@ -504,6 +568,7 @@ public void onLoadError(Loadable ignored, IOException e) {
     currentLoadableExceptionCount = extractedSampleCount > extractedSampleCountAtStartOfLoad ? 1
         : currentLoadableExceptionCount + 1;
     currentLoadableExceptionTimestamp = SystemClock.elapsedRealtime();
+    notifyLoadError(e);
     maybeStartLoading();
   }
 
@@ -661,6 +726,17 @@ private long getRetryDelayMillis(long errorCount) {
     return Math.min((errorCount - 1) * 1000, 5000);
   }
 
+  private void notifyLoadError(final IOException e) {
+    if (eventHandler != null && eventListener != null) {
+      eventHandler.post(new Runnable()  {
+        @Override
+        public void run() {
+          eventListener.onLoadError(eventSourceId, e);
+        }
+      });
+    }
+  }
+
   /**
    * Extension of {@link DefaultTrackOutput} that increments a shared counter of the total number
    * of extracted samples.