Remove TrackInfo from the SampleExtractor interface.

library/src/main/java/com/google/android/exoplayer/source/DefaultSampleSource.java

@@ -62,9 +62,14 @@ public final class DefaultSampleSource implements SampleSource {
 
     if (sampleExtractor.prepare()) {
       prepared = true;
-      trackInfos = sampleExtractor.getTrackInfos();
-      trackStates = new int[trackInfos.length];
-      pendingDiscontinuities = new boolean[trackInfos.length];
+      int trackCount = sampleExtractor.getTrackCount();
+      trackStates = new int[trackCount];
+      pendingDiscontinuities = new boolean[trackCount];
+      trackInfos = new TrackInfo[trackCount];
+      for (int track = 0; track < trackCount; track++) {
+        String mimeType = sampleExtractor.getMediaFormat(track).mimeType;
+        trackInfos[track] = new TrackInfo(mimeType, sampleExtractor.getDurationUs(track));
+      }
     }
 
     return prepared;
@@ -119,7 +124,8 @@ public final class DefaultSampleSource implements SampleSource {
       return NOTHING_READ;
     }
     if (trackStates[track] != TRACK_STATE_FORMAT_SENT) {
-      sampleExtractor.getTrackMediaFormat(track, formatHolder);
+      formatHolder.format = sampleExtractor.getMediaFormat(track);
+      formatHolder.drmInitData = sampleExtractor.getDrmInitData(track);
       trackStates[track] = TRACK_STATE_FORMAT_SENT;
       return FORMAT_READ;
     }

library/src/main/java/com/google/android/exoplayer/source/FrameworkSampleExtractor.java

@@ -17,10 +17,8 @@ package com.google.android.exoplayer.source;
 
 import com.google.android.exoplayer.C;
 import com.google.android.exoplayer.MediaFormat;
-import com.google.android.exoplayer.MediaFormatHolder;
 import com.google.android.exoplayer.SampleHolder;
 import com.google.android.exoplayer.SampleSource;
-import com.google.android.exoplayer.TrackInfo;
 import com.google.android.exoplayer.TrackRenderer;
 import com.google.android.exoplayer.util.Assertions;
 import com.google.android.exoplayer.util.Util;
@@ -53,8 +51,6 @@ public final class FrameworkSampleExtractor implements SampleExtractor {
 
   private final MediaExtractor mediaExtractor;
 
-  private TrackInfo[] trackInfos;
-
   /**
    * Instantiates a new sample extractor reading from the specified {@code uri}.
    *
@@ -106,25 +102,10 @@ public final class FrameworkSampleExtractor implements SampleExtractor {
       mediaExtractor.setDataSource(fileDescriptor, fileDescriptorOffset, fileDescriptorLength);
     }
 
-    int trackCount = mediaExtractor.getTrackCount();
-    trackInfos = new TrackInfo[trackCount];
-    for (int i = 0; i < trackCount; i++) {
-      android.media.MediaFormat format = mediaExtractor.getTrackFormat(i);
-      long durationUs = format.containsKey(android.media.MediaFormat.KEY_DURATION)
-          ? format.getLong(android.media.MediaFormat.KEY_DURATION) : C.UNKNOWN_TIME_US;
-      String mime = format.getString(android.media.MediaFormat.KEY_MIME);
-      trackInfos[i] = new TrackInfo(mime, durationUs);
-    }
-
     return true;
   }
 
   @Override
-  public TrackInfo[] getTrackInfos() {
-    return trackInfos;
-  }
-
-  @Override
   public void selectTrack(int index) {
     mediaExtractor.selectTrack(index);
   }
@@ -151,10 +132,25 @@ public final class FrameworkSampleExtractor implements SampleExtractor {
   }
 
   @Override
-  public void getTrackMediaFormat(int track, MediaFormatHolder mediaFormatHolder) {
-    mediaFormatHolder.format =
-        MediaFormat.createFromFrameworkMediaFormatV16(mediaExtractor.getTrackFormat(track));
-    mediaFormatHolder.drmInitData = Util.SDK_INT >= 18 ? getPsshInfoV18() : null;
+  public int getTrackCount() {
+    return mediaExtractor.getTrackCount();
+  }
+
+  @Override
+  public MediaFormat getMediaFormat(int track) {
+    return MediaFormat.createFromFrameworkMediaFormatV16(mediaExtractor.getTrackFormat(track));
+  }
+
+  @Override
+  public Map<UUID, byte[]> getDrmInitData(int track) {
+    return Util.SDK_INT >= 18 ? getPsshInfoV18() : null;
+  }
+
+  @Override
+  public long getDurationUs(int track) {
+    android.media.MediaFormat format = mediaExtractor.getTrackFormat(track);
+    return format.containsKey(android.media.MediaFormat.KEY_DURATION)
+        ? format.getLong(android.media.MediaFormat.KEY_DURATION) : C.UNKNOWN_TIME_US;
   }
 
   @Override

library/src/main/java/com/google/android/exoplayer/source/SampleExtractor.java

@@ -16,19 +16,19 @@
 package com.google.android.exoplayer.source;
 
 import com.google.android.exoplayer.MediaFormat;
-import com.google.android.exoplayer.MediaFormatHolder;
 import com.google.android.exoplayer.SampleHolder;
 import com.google.android.exoplayer.SampleSource;
-import com.google.android.exoplayer.TrackInfo;
 import com.google.android.exoplayer.TrackRenderer;
 
 import java.io.IOException;
+import java.util.Map;
+import java.util.UUID;
 
 /**
  * Extractor for reading track metadata and samples stored in tracks.
  *
  * <p>Call {@link #prepare} until it returns {@code true}, then access track metadata via
- * {@link #getTrackInfos} and {@link #getTrackMediaFormat}.
+ * {@link #getMediaFormat}.
  *
  * <p>Pass indices of tracks to read from to {@link #selectTrack}. A track can later be deselected
  * by calling {@link #deselectTrack}. It is safe to select/deselect tracks after reading sample
@@ -46,9 +46,6 @@ public interface SampleExtractor {
    */
   boolean prepare() throws IOException;
 
-  /** Returns track information about all tracks that can be selected. */
-  TrackInfo[] getTrackInfos();
-
   /** Selects the track at {@code index} for reading sample data. */
   void selectTrack(int index);
 
@@ -75,8 +72,17 @@ public interface SampleExtractor {
    */
   void seekTo(long positionUs);
 
-  /** Stores the {@link MediaFormat} of {@code track}. */
-  void getTrackMediaFormat(int track, MediaFormatHolder mediaFormatHolder);
+  /** Returns the number of tracks, if {@link #prepare} has returned {@code true}. */
+  int getTrackCount();
+
+  /** Returns the {@link MediaFormat} of {@code track}. */
+  MediaFormat getMediaFormat(int track);
+
+  /** Returns the DRM initialization data for {@code track}. */
+  Map<UUID, byte[]> getDrmInitData(int track);
+
+  /** Returns the duration of {@code track} in microseconds. */
+  long getDurationUs(int track);
 
   /**
    * Reads the next sample in the track at index {@code track} into {@code sampleHolder}, returning