Use TrackKey in place of RepresentetionKey, StreamKey, RenditionKey

------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=199767518

Use TrackKey in place of RepresentetionKey, StreamKey, RenditionKey
------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=199767518
a406dc8b · eguven · Oliver Woodman · 8e65696f · a406dc8b · a406dc8b
Commit a406dc8b authored Jun 08, 2018 by eguven Committed by Oliver Woodman Jun 18, 2018
Showing with 255 additions and 400 deletions
demos/main/src/main/java/com/google/android/exoplayer2/demo/DownloadTracker.java
demos/main/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java
library/core/src/main/java/com/google/android/exoplayer2/offline/FilterableManifest.java
library/core/src/main/java/com/google/android/exoplayer2/offline/FilteringManifestParser.java
library/core/src/main/java/com/google/android/exoplayer2/offline/SegmentDownloadAction.java
library/core/src/main/java/com/google/android/exoplayer2/offline/SegmentDownloader.java
library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/manifest/StreamKey.java → library/core/src/main/java/com/google/android/exoplayer2/offline/StreamKey.java
library/dash/src/main/java/com/google/android/exoplayer2/source/dash/manifest/DashManifest.java
library/dash/src/main/java/com/google/android/exoplayer2/source/dash/manifest/RepresentationKey.java
library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadAction.java
library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadHelper.java
library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloader.java
library/dash/src/test/java/com/google/android/exoplayer2/source/dash/manifest/DashManifestTest.java
library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadActionTest.java
library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DashDownloaderTest.java
library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DownloadManagerDashTest.java
library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DownloadServiceDashTest.java
library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloadAction.java
library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloadHelper.java
library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloader.java
--- a/demos/main/src/main/java/com/google/android/exoplayer2/demo/DownloadTracker.java
+++ b/demos/main/src/main/java/com/google/android/exoplayer2/demo/DownloadTracker.java
@@ -37,6 +37,7 @@ import com.google.android.exoplayer2.offline.DownloadManager.TaskState;
 import com.google.android.exoplayer2.offline.DownloadService;
 import com.google.android.exoplayer2.offline.ProgressiveDownloadHelper;
 import com.google.android.exoplayer2.offline.SegmentDownloadAction;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.offline.TrackKey;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
@@ -111,7 +112,7 @@ public class DownloadTracker implements DownloadManager.Listener {
  }
  @SuppressWarnings("unchecked")
-  public <K> List<K> getOfflineStreamKeys(Uri uri) {
+  public List<StreamKey> getOfflineStreamKeys(Uri uri) {
    if (!trackedDownloadStates.containsKey(uri)) {
      return Collections.emptyList();
    }
@@ -282,6 +283,7 @@ public class DownloadTracker implements DownloadManager.Listener {
      Toast.makeText(
              context.getApplicationContext(), R.string.download_start_error, Toast.LENGTH_LONG)
          .show();
+      Log.e(TAG, "Failed to start download", e);
    }
    @Override

--- a/demos/main/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java
+++ b/demos/main/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java
@@ -49,6 +49,7 @@ import com.google.android.exoplayer2.drm.UnsupportedDrmException;
 import com.google.android.exoplayer2.mediacodec.MediaCodecRenderer.DecoderInitializationException;
 import com.google.android.exoplayer2.mediacodec.MediaCodecUtil.DecoderQueryException;
 import com.google.android.exoplayer2.offline.FilteringManifestParser;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.source.BehindLiveWindowException;
 import com.google.android.exoplayer2.source.ConcatenatingMediaSource;
 import com.google.android.exoplayer2.source.ExtractorMediaSource;
@@ -59,14 +60,11 @@ import com.google.android.exoplayer2.source.ads.AdsMediaSource;
 import com.google.android.exoplayer2.source.dash.DashMediaSource;
 import com.google.android.exoplayer2.source.dash.DefaultDashChunkSource;
 import com.google.android.exoplayer2.source.dash.manifest.DashManifestParser;
-import com.google.android.exoplayer2.source.dash.manifest.RepresentationKey;
 import com.google.android.exoplayer2.source.hls.HlsMediaSource;
 import com.google.android.exoplayer2.source.hls.playlist.HlsPlaylistParser;
-import com.google.android.exoplayer2.source.hls.playlist.RenditionKey;
 import com.google.android.exoplayer2.source.smoothstreaming.DefaultSsChunkSource;
 import com.google.android.exoplayer2.source.smoothstreaming.SsMediaSource;
 import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsManifestParser;
-import com.google.android.exoplayer2.source.smoothstreaming.manifest.StreamKey;
 import com.google.android.exoplayer2.trackselection.AdaptiveTrackSelection;
 import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
 import com.google.android.exoplayer2.trackselection.MappingTrackSelector.MappedTrackInfo;
@@ -446,22 +444,19 @@ public class PlayerActivity extends Activity
                new DefaultDashChunkSource.Factory(mediaDataSourceFactory),
                buildDataSourceFactory(false))
            .setManifestParser(
-                new FilteringManifestParser<>(
+                new FilteringManifestParser<>(new DashManifestParser(), getOfflineStreamKeys(uri)))
-                    new DashManifestParser(), (List<RepresentationKey>) getOfflineStreamKeys(uri)))
            .createMediaSource(uri);
      case C.TYPE_SS:
        return new SsMediaSource.Factory(
                new DefaultSsChunkSource.Factory(mediaDataSourceFactory),
                buildDataSourceFactory(false))
            .setManifestParser(
-                new FilteringManifestParser<>(
+                new FilteringManifestParser<>(new SsManifestParser(), getOfflineStreamKeys(uri)))
-                    new SsManifestParser(), (List<StreamKey>) getOfflineStreamKeys(uri)))
            .createMediaSource(uri);
      case C.TYPE_HLS:
        return new HlsMediaSource.Factory(mediaDataSourceFactory)
            .setPlaylistParser(
-                new FilteringManifestParser<>(
+                new FilteringManifestParser<>(new HlsPlaylistParser(), getOfflineStreamKeys(uri)))
-                    new HlsPlaylistParser(), (List<RenditionKey>) getOfflineStreamKeys(uri)))
            .createMediaSource(uri);
      case C.TYPE_OTHER:
        return new ExtractorMediaSource.Factory(mediaDataSourceFactory).createMediaSource(uri);
@@ -471,7 +466,7 @@ public class PlayerActivity extends Activity
    }
  }
-  private List<?> getOfflineStreamKeys(Uri uri) {
+  private List<StreamKey> getOfflineStreamKeys(Uri uri) {
    return ((DemoApplication) getApplication()).getDownloadTracker().getOfflineStreamKeys(uri);
  }

--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/FilterableManifest.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/FilterableManifest.java
@@ -22,9 +22,8 @@ import java.util.List;
 * keys.
 *
 * @param <T> The manifest type.
- * @param <K> The stream key type.
 */
-public interface FilterableManifest<T, K> {
+public interface FilterableManifest<T> {
  /**
   * Returns a copy of the manifest including only the streams specified by the given keys. If the
@@ -33,5 +32,5 @@ public interface FilterableManifest<T, K> {
   * @param streamKeys A non-empty list of stream keys.
   * @return The filtered manifest.
   */
-  T copy(List<K> streamKeys);
+  T copy(List<StreamKey> streamKeys);
 }
--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/FilteringManifestParser.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/FilteringManifestParser.java
@@ -21,25 +21,24 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.util.List;
-/** A manifest parser that includes only the tracks identified by the given track keys. */
+/** A manifest parser that includes only the streams identified by the given stream keys. */
-public final class FilteringManifestParser<T extends FilterableManifest<T, K>, K>
+public final class FilteringManifestParser<T extends FilterableManifest<T>> implements Parser<T> {
-    implements Parser<T> {
  private final Parser<T> parser;
-  private final List<K> trackKeys;
+  private final List<StreamKey> streamKeys;
  /**
   * @param parser A parser for the manifest that will be filtered.
-   * @param trackKeys The track keys. If null or empty then filtering will not occur.
+   * @param streamKeys The stream keys. If null or empty then filtering will not occur.
   */
-  public FilteringManifestParser(Parser<T> parser, List<K> trackKeys) {
+  public FilteringManifestParser(Parser<T> parser, List<StreamKey> streamKeys) {
    this.parser = parser;
-    this.trackKeys = trackKeys;
+    this.streamKeys = streamKeys;
  }
  @Override
  public T parse(Uri uri, InputStream inputStream) throws IOException {
    T manifest = parser.parse(uri, inputStream);
-    return trackKeys == null || trackKeys.isEmpty() ? manifest : manifest.copy(trackKeys);
+    return streamKeys == null || streamKeys.isEmpty() ? manifest : manifest.copy(streamKeys);
  }
 }
--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/SegmentDownloadAction.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/SegmentDownloadAction.java
@@ -25,19 +25,11 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
-/**
+/** {@link DownloadAction} for {@link SegmentDownloader}s. */
- * {@link DownloadAction} for {@link SegmentDownloader}s.
+public abstract class SegmentDownloadAction extends DownloadAction {
- *
- * @param <K> The type of the representation key object.
- */
-public abstract class SegmentDownloadAction<K extends Comparable<K>> extends DownloadAction {
-  /**
+  /** Base class for {@link SegmentDownloadAction} {@link Deserializer}s. */
-   * Base class for {@link SegmentDownloadAction} {@link Deserializer}s.
+  protected abstract static class SegmentDownloadActionDeserializer extends Deserializer {
-   *
-   * @param <K> The type of the representation key object.
-   */
-  protected abstract static class SegmentDownloadActionDeserializer<K> extends Deserializer {
    public SegmentDownloadActionDeserializer(String type, int version) {
      super(type, version);
@@ -52,7 +44,7 @@ public abstract class SegmentDownloadAction<K extends Comparable<K>> extends Dow
      byte[] data = new byte[dataLength];
      input.readFully(data);
      int keyCount = input.readInt();
-      List<K> keys = new ArrayList<>();
+      List<StreamKey> keys = new ArrayList<>();
      for (int i = 0; i < keyCount; i++) {
        keys.add(readKey(input));
      }
@@ -60,14 +52,14 @@ public abstract class SegmentDownloadAction<K extends Comparable<K>> extends Dow
    }
    /** Deserializes a key from the {@code input}. */
-    protected abstract K readKey(DataInputStream input) throws IOException;
+    protected abstract StreamKey readKey(DataInputStream input) throws IOException;
    /** Returns a {@link DownloadAction}. */
    protected abstract DownloadAction createDownloadAction(
-        Uri manifestUri, boolean isRemoveAction, byte[] data, List<K> keys);
+        Uri manifestUri, boolean isRemoveAction, byte[] data, List<StreamKey> keys);
  }
-  public final List<K> keys;
+  public final List<StreamKey> keys;
  /**
   * @param type The type of the action.
@@ -84,13 +76,13 @@ public abstract class SegmentDownloadAction<K extends Comparable<K>> extends Dow
      Uri uri,
      boolean isRemoveAction,
      @Nullable byte[] data,
-      List<K> keys) {
+      List<StreamKey> keys) {
    super(type, version, uri, isRemoveAction, data);
    if (isRemoveAction) {
      Assertions.checkArgument(keys.isEmpty());
      this.keys = Collections.emptyList();
    } else {
-      ArrayList<K> mutableKeys = new ArrayList<>(keys);
+      ArrayList<StreamKey> mutableKeys = new ArrayList<>(keys);
      Collections.sort(mutableKeys);
      this.keys = Collections.unmodifiableList(mutableKeys);
    }
@@ -109,7 +101,7 @@ public abstract class SegmentDownloadAction<K extends Comparable<K>> extends Dow
  }
  /** Serializes the {@code key} into the {@code output}. */
-  protected abstract void writeKey(DataOutputStream output, K key) throws IOException;
+  protected abstract void writeKey(DataOutputStream output, StreamKey key) throws IOException;
  @Override
  public boolean equals(@Nullable Object o) {
@@ -119,7 +111,7 @@ public abstract class SegmentDownloadAction<K extends Comparable<K>> extends Dow
    if (!super.equals(o)) {
      return false;
    }
-    SegmentDownloadAction<?> that = (SegmentDownloadAction<?>) o;
+    SegmentDownloadAction that = (SegmentDownloadAction) o;
    return keys.equals(that.keys);
  }

--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/SegmentDownloader.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/SegmentDownloader.java
@@ -35,10 +35,8 @@ import java.util.concurrent.atomic.AtomicBoolean;
 * Base class for multi segment stream downloaders.
 *
 * @param <M> The type of the manifest object.
- * @param <K> The type of the streams key object.
 */
-public abstract class SegmentDownloader<M extends FilterableManifest<M, K>, K>
+public abstract class SegmentDownloader<M extends FilterableManifest<M>> implements Downloader {
-    implements Downloader {
  /** Smallest unit of content to be downloaded. */
  protected static class Segment implements Comparable<Segment> {
@@ -68,7 +66,7 @@ public abstract class SegmentDownloader<M extends FilterableManifest<M, K>, K>
  private final Cache cache;
  private final CacheDataSource dataSource;
  private final CacheDataSource offlineDataSource;
-  private final ArrayList<K> streamKeys;
+  private final ArrayList<StreamKey> streamKeys;
  private final AtomicBoolean isCanceled;
  private volatile int totalSegments;
@@ -82,7 +80,7 @@ public abstract class SegmentDownloader<M extends FilterableManifest<M, K>, K>
   * @param constructorHelper A {@link DownloaderConstructorHelper} instance.
   */
  public SegmentDownloader(
-      Uri manifestUri, List<K> streamKeys, DownloaderConstructorHelper constructorHelper) {
+      Uri manifestUri, List<StreamKey> streamKeys, DownloaderConstructorHelper constructorHelper) {
    this.manifestUri = manifestUri;
    this.streamKeys = new ArrayList<>(streamKeys);
    this.cache = constructorHelper.getCache();

--- a/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/manifest/StreamKey.java
+++ b/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/manifest/StreamKey.java
 /*
- * Copyright (C) 2017 The Android Open Source Project
+ * Copyright (C) 2018 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.
@@ -13,25 +13,46 @@
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
-package com.google.android.exoplayer2.source.smoothstreaming.manifest;
+package com.google.android.exoplayer2.offline;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
-/** Uniquely identifies a track in a {@link SsManifest}. */
+/**
+ * Identifies a given track by the index of the containing period, the index of the containing group
+ * within the period, and the index of the track within the group.
+ */
 public final class StreamKey implements Comparable<StreamKey> {
-  public final int streamElementIndex;
+  /** The period index. */
+  public final int periodIndex;
+  /** The group index. */
+  public final int groupIndex;
+  /** The track index. */
  public final int trackIndex;
-  public StreamKey(int streamElementIndex, int trackIndex) {
+  /**
-    this.streamElementIndex = streamElementIndex;
+   * @param groupIndex The group index.
+   * @param trackIndex The track index.
+   */
+  public StreamKey(int groupIndex, int trackIndex) {
+    this(0, groupIndex, trackIndex);
+  }
+  /**
+   * @param periodIndex The period index.
+   * @param groupIndex The group index.
+   * @param trackIndex The track index.
+   */
+  public StreamKey(int periodIndex, int groupIndex, int trackIndex) {
+    this.periodIndex = periodIndex;
+    this.groupIndex = groupIndex;
    this.trackIndex = trackIndex;
  }
  @Override
  public String toString() {
-    return streamElementIndex + "." + trackIndex;
+    return periodIndex + "." + groupIndex + "." + trackIndex;
  }
  @Override
@@ -44,12 +65,15 @@ public final class StreamKey implements Comparable<StreamKey> {
    }
    StreamKey that = (StreamKey) o;
-    return streamElementIndex == that.streamElementIndex && trackIndex == that.trackIndex;
+    return periodIndex == that.periodIndex
+        && groupIndex == that.groupIndex
+        && trackIndex == that.trackIndex;
  }
  @Override
  public int hashCode() {
-    int result = streamElementIndex;
+    int result = periodIndex;
+    result = 31 * result + groupIndex;
    result = 31 * result + trackIndex;
    return result;
  }
@@ -58,9 +82,12 @@ public final class StreamKey implements Comparable<StreamKey> {
  @Override
  public int compareTo(@NonNull StreamKey o) {
-    int result = streamElementIndex - o.streamElementIndex;
+    int result = periodIndex - o.periodIndex;
    if (result == 0) {
-      result = trackIndex - o.trackIndex;
+      result = groupIndex - o.groupIndex;
+      if (result == 0) {
+        result = trackIndex - o.trackIndex;
+      }
    }
    return result;
  }

--- a/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/manifest/DashManifest.java
+++ b/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/manifest/DashManifest.java
@@ -18,6 +18,7 @@ package com.google.android.exoplayer2.source.dash.manifest;
 import android.net.Uri;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.offline.FilterableManifest;
+import com.google.android.exoplayer2.offline.StreamKey;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.LinkedList;
@@ -27,7 +28,7 @@ import java.util.List;
 * Represents a DASH media presentation description (mpd), as defined by ISO/IEC 23009-1:2014
 * Section 5.3.1.2.
 */
-public class DashManifest implements FilterableManifest<DashManifest, RepresentationKey> {
+public class DashManifest implements FilterableManifest<DashManifest> {
  /**
   * The {@code availabilityStartTime} value in milliseconds since epoch, or {@link C#TIME_UNSET} if
@@ -123,10 +124,10 @@ public class DashManifest implements FilterableManifest<DashManifest, Representa
  }
  @Override
-  public final DashManifest copy(List<RepresentationKey> streamKeys) {
+  public final DashManifest copy(List<StreamKey> streamKeys) {
-    LinkedList<RepresentationKey> keys = new LinkedList<>(streamKeys);
+    LinkedList<StreamKey> keys = new LinkedList<>(streamKeys);
    Collections.sort(keys);
-    keys.add(new RepresentationKey(-1, -1, -1)); // Add a stopper key to the end
+    keys.add(new StreamKey(-1, -1, -1)); // Add a stopper key to the end
    ArrayList<Period> copyPeriods = new ArrayList<>();
    long shiftMs = 0;
@@ -153,21 +154,21 @@ public class DashManifest implements FilterableManifest<DashManifest, Representa
  }
  private static ArrayList<AdaptationSet> copyAdaptationSets(
-      List<AdaptationSet> adaptationSets, LinkedList<RepresentationKey> keys) {
+      List<AdaptationSet> adaptationSets, LinkedList<StreamKey> keys) {
-    RepresentationKey key = keys.poll();
+    StreamKey key = keys.poll();
    int periodIndex = key.periodIndex;
    ArrayList<AdaptationSet> copyAdaptationSets = new ArrayList<>();
    do {
-      int adaptationSetIndex = key.adaptationSetIndex;
+      int adaptationSetIndex = key.groupIndex;
      AdaptationSet adaptationSet = adaptationSets.get(adaptationSetIndex);
      List<Representation> representations = adaptationSet.representations;
      ArrayList<Representation> copyRepresentations = new ArrayList<>();
      do {
-        Representation representation = representations.get(key.representationIndex);
+        Representation representation = representations.get(key.trackIndex);
        copyRepresentations.add(representation);
        key = keys.poll();
-      } while(key.periodIndex == periodIndex && key.adaptationSetIndex == adaptationSetIndex);
+      } while (key.periodIndex == periodIndex && key.groupIndex == adaptationSetIndex);
      copyAdaptationSets.add(new AdaptationSet(adaptationSet.id, adaptationSet.type,
          copyRepresentations, adaptationSet.accessibilityDescriptors,

--- a/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/manifest/RepresentationKey.java
+++ b/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/manifest/RepresentationKey.java
-/*
- * 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.source.dash.manifest;
-import android.support.annotation.NonNull;
-import android.support.annotation.Nullable;
-/** Uniquely identifies a {@link Representation} in a {@link DashManifest}. */
-public final class RepresentationKey implements Comparable<RepresentationKey> {
-  public final int periodIndex;
-  public final int adaptationSetIndex;
-  public final int representationIndex;
-  public RepresentationKey(int periodIndex, int adaptationSetIndex, int representationIndex) {
-    this.periodIndex = periodIndex;
-    this.adaptationSetIndex = adaptationSetIndex;
-    this.representationIndex = representationIndex;
-  }
-  @Override
-  public String toString() {
-    return periodIndex + "." + adaptationSetIndex + "." + representationIndex;
-  }
-  @Override
-  public boolean equals(@Nullable Object o) {
-    if (this == o) {
-      return true;
-    }
-    if (o == null || getClass() != o.getClass()) {
-      return false;
-    }
-    RepresentationKey that = (RepresentationKey) o;
-    return periodIndex == that.periodIndex
-        && adaptationSetIndex == that.adaptationSetIndex
-        && representationIndex == that.representationIndex;
-  }
-  @Override
-  public int hashCode() {
-    int result = periodIndex;
-    result = 31 * result + adaptationSetIndex;
-    result = 31 * result + representationIndex;
-    return result;
-  }
-  // Comparable implementation.
-  @Override
-  public int compareTo(@NonNull RepresentationKey o) {
-    int result = periodIndex - o.periodIndex;
-    if (result == 0) {
-      result = adaptationSetIndex - o.adaptationSetIndex;
-      if (result == 0) {
-        result = representationIndex - o.representationIndex;
-      }
-    }
-    return result;
-  }
-}
--- a/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadAction.java
+++ b/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadAction.java
@@ -20,29 +20,32 @@ import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.offline.DownloadAction;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
 import com.google.android.exoplayer2.offline.SegmentDownloadAction;
-import com.google.android.exoplayer2.source.dash.manifest.RepresentationKey;
+import com.google.android.exoplayer2.offline.StreamKey;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
 import java.util.List;
 /** An action to download or remove downloaded DASH streams. */
-public final class DashDownloadAction extends SegmentDownloadAction<RepresentationKey> {
+public final class DashDownloadAction extends SegmentDownloadAction {
  private static final String TYPE = "dash";
  private static final int VERSION = 0;
  public static final Deserializer DESERIALIZER =
-      new SegmentDownloadActionDeserializer<RepresentationKey>(TYPE, VERSION) {
+      new SegmentDownloadActionDeserializer(TYPE, VERSION) {
        @Override
-        protected RepresentationKey readKey(DataInputStream input) throws IOException {
+        protected StreamKey readKey(DataInputStream input) throws IOException {
-          return new RepresentationKey(input.readInt(), input.readInt(), input.readInt());
+          int periodIndex = input.readInt();
+          int groupIndex = input.readInt();
+          int trackIndex = input.readInt();
+          return new StreamKey(periodIndex, groupIndex, trackIndex);
        }
        @Override
        protected DownloadAction createDownloadAction(
-            Uri uri, boolean isRemoveAction, byte[] data, List<RepresentationKey> keys) {
+            Uri uri, boolean isRemoveAction, byte[] data, List<StreamKey> keys) {
          return new DashDownloadAction(uri, isRemoveAction, data, keys);
        }
      };
@@ -55,7 +58,7 @@ public final class DashDownloadAction extends SegmentDownloadAction<Representati
   *     downloaded. If {@code removeAction} is true, {@code keys} must be empty.
   */
  public DashDownloadAction(
-      Uri uri, boolean isRemoveAction, @Nullable byte[] data, List<RepresentationKey> keys) {
+      Uri uri, boolean isRemoveAction, @Nullable byte[] data, List<StreamKey> keys) {
    super(TYPE, VERSION, uri, isRemoveAction, data, keys);
  }
@@ -65,10 +68,10 @@ public final class DashDownloadAction extends SegmentDownloadAction<Representati
  }
  @Override
-  protected void writeKey(DataOutputStream output, RepresentationKey key) throws IOException {
+  protected void writeKey(DataOutputStream output, StreamKey key) throws IOException {
    output.writeInt(key.periodIndex);
-    output.writeInt(key.adaptationSetIndex);
+    output.writeInt(key.groupIndex);
-    output.writeInt(key.representationIndex);
+    output.writeInt(key.trackIndex);
  }
 }
--- a/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadHelper.java
+++ b/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadHelper.java
@@ -19,6 +19,7 @@ import android.net.Uri;
 import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.offline.DownloadHelper;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.offline.TrackKey;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
@@ -26,7 +27,6 @@ import com.google.android.exoplayer2.source.dash.manifest.AdaptationSet;
 import com.google.android.exoplayer2.source.dash.manifest.DashManifest;
 import com.google.android.exoplayer2.source.dash.manifest.DashManifestParser;
 import com.google.android.exoplayer2.source.dash.manifest.Representation;
-import com.google.android.exoplayer2.source.dash.manifest.RepresentationKey;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.ParsingLoadable;
 import com.google.android.exoplayer2.util.Assertions;
@@ -51,9 +51,8 @@ public final class DashDownloadHelper extends DownloadHelper {
  @Override
  protected void prepareInternal() throws IOException {
-    manifest =
+    DataSource dataSource = manifestDataSourceFactory.createDataSource();
-        ParsingLoadable.load(
+    manifest = ParsingLoadable.load(dataSource, new DashManifestParser(), uri);
-            manifestDataSourceFactory.createDataSource(), new DashManifestParser(), uri);
  }
  /** Returns the DASH manifest. Must not be called until after preparation completes. */
@@ -87,23 +86,20 @@ public final class DashDownloadHelper extends DownloadHelper {
  @Override
  public DashDownloadAction getDownloadAction(@Nullable byte[] data, List<TrackKey> trackKeys) {
-    return new DashDownloadAction(
+    return new DashDownloadAction(uri, /* isRemoveAction= */ false, data, toStreamKeys(trackKeys));
-        uri, /* isRemoveAction= */ false, data, toRepresentationKeys(trackKeys));
  }
  @Override
  public DashDownloadAction getRemoveAction(@Nullable byte[] data) {
-    return new DashDownloadAction(
+    return new DashDownloadAction(uri, /* isRemoveAction= */ true, data, Collections.emptyList());
-        uri, /* isRemoveAction= */ true, data, Collections.<RepresentationKey>emptyList());
  }
-  private static List<RepresentationKey> toRepresentationKeys(List<TrackKey> trackKeys) {
+  private static List<StreamKey> toStreamKeys(List<TrackKey> trackKeys) {
-    List<RepresentationKey> representationKeys = new ArrayList<>(trackKeys.size());
+    List<StreamKey> streamKeys = new ArrayList<>(trackKeys.size());
    for (int i = 0; i < trackKeys.size(); i++) {
      TrackKey trackKey = trackKeys.get(i);
-      representationKeys.add(
+      streamKeys.add(new StreamKey(trackKey.periodIndex, trackKey.groupIndex, trackKey.trackIndex));
-          new RepresentationKey(trackKey.periodIndex, trackKey.groupIndex, trackKey.trackIndex));
    }
-    return representationKeys;
+    return streamKeys;
  }
 }
--- a/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloader.java
+++ b/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloader.java
@@ -22,6 +22,7 @@ import com.google.android.exoplayer2.extractor.ChunkIndex;
 import com.google.android.exoplayer2.offline.DownloadException;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
 import com.google.android.exoplayer2.offline.SegmentDownloader;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.source.dash.DashSegmentIndex;
 import com.google.android.exoplayer2.source.dash.DashUtil;
 import com.google.android.exoplayer2.source.dash.DashWrappingSegmentIndex;
@@ -30,7 +31,6 @@ import com.google.android.exoplayer2.source.dash.manifest.DashManifest;
 import com.google.android.exoplayer2.source.dash.manifest.Period;
 import com.google.android.exoplayer2.source.dash.manifest.RangedUri;
 import com.google.android.exoplayer2.source.dash.manifest.Representation;
-import com.google.android.exoplayer2.source.dash.manifest.RepresentationKey;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.DataSpec;
 import java.io.IOException;
@@ -51,9 +51,7 @@ import java.util.List;
 * // period.
 * DashDownloader dashDownloader =
 *     new DashDownloader(
- *         manifestUrl,
+ *         manifestUrl, Collections.singletonList(new StreamKey(0, 0, 0)), constructorHelper);
- *         Collections.singletonList(new RepresentationKey(0, 0, 0)),
- *         constructorHelper);
 * // Perform the download.
 * dashDownloader.download();
 * // Access downloaded data using CacheDataSource
@@ -61,19 +59,17 @@ import java.util.List;
 *     new CacheDataSource(cache, factory.createDataSource(), CacheDataSource.FLAG_BLOCK_ON_CACHE);
 * }</pre>
 */
-public final class DashDownloader extends SegmentDownloader<DashManifest, RepresentationKey> {
+public final class DashDownloader extends SegmentDownloader<DashManifest> {
  /**
   * @param manifestUri The {@link Uri} of the manifest to be downloaded.
-   * @param representationKeys Keys defining which representations in the manifest should be
+   * @param streamKeys Keys defining which representations in the manifest should be selected for
-   *     selected for download. If empty, all representations are downloaded.
+   *     download. If empty, all representations are downloaded.
   * @param constructorHelper A {@link DownloaderConstructorHelper} instance.
   */
  public DashDownloader(
-      Uri manifestUri,
+      Uri manifestUri, List<StreamKey> streamKeys, DownloaderConstructorHelper constructorHelper) {
-      List<RepresentationKey> representationKeys,
+    super(manifestUri, streamKeys, constructorHelper);
-      DownloaderConstructorHelper constructorHelper) {
-    super(manifestUri, representationKeys, constructorHelper);
  }
  @Override

--- a/library/dash/src/test/java/com/google/android/exoplayer2/source/dash/manifest/DashManifestTest.java
+++ b/library/dash/src/test/java/com/google/android/exoplayer2/source/dash/manifest/DashManifestTest.java
@@ -19,6 +19,7 @@ import static com.google.common.truth.Truth.assertThat;
 import android.net.Uri;
 import com.google.android.exoplayer2.Format;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.source.dash.manifest.SegmentBase.SingleSegmentBase;
 import java.util.Arrays;
 import java.util.Collections;
@@ -58,17 +59,17 @@ public class DashManifestTest {
                newAdaptationSet(8, representations[2][0]),
                newAdaptationSet(9, representations[2][1])));
-    List<RepresentationKey> keys =
+    List<StreamKey> keys =
        Arrays.asList(
-            new RepresentationKey(0, 0, 0),
+            new StreamKey(0, 0, 0),
-            new RepresentationKey(0, 0, 1),
+            new StreamKey(0, 0, 1),
-            new RepresentationKey(0, 1, 2),
+            new StreamKey(0, 1, 2),
-            new RepresentationKey(1, 0, 1),
+            new StreamKey(1, 0, 1),
-            new RepresentationKey(1, 1, 0),
+            new StreamKey(1, 1, 0),
-            new RepresentationKey(1, 1, 2),
+            new StreamKey(1, 1, 2),
-            new RepresentationKey(2, 0, 1),
+            new StreamKey(2, 0, 1),
-            new RepresentationKey(2, 0, 2),
+            new StreamKey(2, 0, 2),
-            new RepresentationKey(2, 1, 0));
+            new StreamKey(2, 1, 0));
    // Keys don't need to be in any particular order
    Collections.shuffle(keys, new Random(0));
@@ -105,8 +106,7 @@ public class DashManifestTest {
            newPeriod("4", 4, newAdaptationSet(5, representations[1][0])));
    DashManifest copyManifest =
-        sourceManifest.copy(
+        sourceManifest.copy(Arrays.asList(new StreamKey(0, 0, 0), new StreamKey(1, 0, 0)));
-            Arrays.asList(new RepresentationKey(0, 0, 0), new RepresentationKey(1, 0, 0)));
    DashManifest expectedManifest =
        newDashManifest(
@@ -141,12 +141,12 @@ public class DashManifestTest {
    DashManifest copyManifest =
        sourceManifest.copy(
            Arrays.asList(
-                new RepresentationKey(0, 0, 0),
+                new StreamKey(0, 0, 0),
-                new RepresentationKey(0, 0, 1),
+                new StreamKey(0, 0, 1),
-                new RepresentationKey(0, 1, 2),
+                new StreamKey(0, 1, 2),
-                new RepresentationKey(2, 0, 1),
+                new StreamKey(2, 0, 1),
-                new RepresentationKey(2, 0, 2),
+                new StreamKey(2, 0, 2),
-                new RepresentationKey(2, 1, 0)));
+                new StreamKey(2, 1, 0)));
    DashManifest expectedManifest =
        newDashManifest(

--- a/library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadActionTest.java
+++ b/library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadActionTest.java
@@ -21,7 +21,7 @@ import android.net.Uri;
 import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.offline.DownloadAction;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
-import com.google.android.exoplayer2.source.dash.manifest.RepresentationKey;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.upstream.DummyDataSource;
 import com.google.android.exoplayer2.upstream.cache.Cache;
 import java.io.ByteArrayInputStream;
@@ -104,16 +104,13 @@ public class DashDownloadActionTest {
    DashDownloadAction action6 = newAction(uri1, /* isRemoveAction= */ false, /* data= */ null);
    DashDownloadAction action7 =
-        newAction(
+        newAction(uri1, /* isRemoveAction= */ false, /* data= */ null, new StreamKey(0, 0, 0));
-            uri1, /* isRemoveAction= */ false, /* data= */ null, new RepresentationKey(0, 0, 0));
    assertNotEqual(action6, action7);
    DashDownloadAction action8 =
-        newAction(
+        newAction(uri1, /* isRemoveAction= */ false, /* data= */ null, new StreamKey(1, 1, 1));
-            uri1, /* isRemoveAction= */ false, /* data= */ null, new RepresentationKey(1, 1, 1));
    DashDownloadAction action9 =
-        newAction(
+        newAction(uri1, /* isRemoveAction= */ false, /* data= */ null, new StreamKey(0, 0, 0));
-            uri1, /* isRemoveAction= */ false, /* data= */ null, new RepresentationKey(0, 0, 0));
    assertNotEqual(action8, action9);
    DashDownloadAction action10 = newAction(uri1, /* isRemoveAction= */ true, /* data= */ null);
@@ -125,27 +122,26 @@ public class DashDownloadActionTest {
            uri1,
            /* isRemoveAction= */ false,
            /* data= */ null,
-            new RepresentationKey(0, 0, 0),
+            new StreamKey(0, 0, 0),
-            new RepresentationKey(1, 1, 1));
+            new StreamKey(1, 1, 1));
    DashDownloadAction action13 =
        newAction(
            uri1,
            /* isRemoveAction= */ false,
            /* data= */ null,
-            new RepresentationKey(1, 1, 1),
+            new StreamKey(1, 1, 1),
-            new RepresentationKey(0, 0, 0));
+            new StreamKey(0, 0, 0));
    assertEqual(action12, action13);
    DashDownloadAction action14 =
-        newAction(
+        newAction(uri1, /* isRemoveAction= */ false, /* data= */ null, new StreamKey(0, 0, 0));
-            uri1, /* isRemoveAction= */ false, /* data= */ null, new RepresentationKey(0, 0, 0));
    DashDownloadAction action15 =
        newAction(
            uri1,
            /* isRemoveAction= */ false,
            /* data= */ null,
-            new RepresentationKey(1, 1, 1),
+            new StreamKey(1, 1, 1),
-            new RepresentationKey(0, 0, 0));
+            new StreamKey(0, 0, 0));
    assertNotEqual(action14, action15);
    DashDownloadAction action16 = newAction(uri1, /* isRemoveAction= */ false, /* data= */ null);
@@ -168,8 +164,8 @@ public class DashDownloadActionTest {
            uri2,
            /* isRemoveAction= */ false,
            /* data= */ null,
-            new RepresentationKey(0, 0, 0),
+            new StreamKey(0, 0, 0),
-            new RepresentationKey(1, 1, 1)));
+            new StreamKey(1, 1, 1)));
  }
  private static void assertNotEqual(DashDownloadAction action1, DashDownloadAction action2) {
@@ -197,8 +193,8 @@ public class DashDownloadActionTest {
  }
  private static DashDownloadAction newAction(
-      Uri uri, boolean isRemoveAction, @Nullable byte[] data, RepresentationKey... keys) {
+      Uri uri, boolean isRemoveAction, @Nullable byte[] data, StreamKey... keys) {
-    ArrayList<RepresentationKey> keysList = new ArrayList<>();
+    ArrayList<StreamKey> keysList = new ArrayList<>();
    Collections.addAll(keysList, keys);
    return new DashDownloadAction(uri, isRemoveAction, data, keysList);
  }

--- a/library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DashDownloaderTest.java
+++ b/library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DashDownloaderTest.java
@@ -27,7 +27,7 @@ import static org.mockito.Mockito.when;
 import com.google.android.exoplayer2.offline.DownloadException;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
-import com.google.android.exoplayer2.source.dash.manifest.RepresentationKey;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.testutil.FakeDataSet;
 import com.google.android.exoplayer2.testutil.FakeDataSource;
 import com.google.android.exoplayer2.testutil.FakeDataSource.Factory;
@@ -77,7 +77,7 @@ public class DashDownloaderTest {
            .setRandomData("audio_segment_2", 5)
            .setRandomData("audio_segment_3", 6);
-    DashDownloader dashDownloader = getDashDownloader(fakeDataSet, new RepresentationKey(0, 0, 0));
+    DashDownloader dashDownloader = getDashDownloader(fakeDataSet, new StreamKey(0, 0, 0));
    dashDownloader.download();
    assertCachedData(cache, fakeDataSet);
  }
@@ -96,7 +96,7 @@ public class DashDownloaderTest {
            .setRandomData("audio_segment_2", 5)
            .setRandomData("audio_segment_3", 6);
-    DashDownloader dashDownloader = getDashDownloader(fakeDataSet, new RepresentationKey(0, 0, 0));
+    DashDownloader dashDownloader = getDashDownloader(fakeDataSet, new StreamKey(0, 0, 0));
    dashDownloader.download();
    assertCachedData(cache, fakeDataSet);
  }
@@ -115,8 +115,7 @@ public class DashDownloaderTest {
            .setRandomData("text_segment_3", 3);
    DashDownloader dashDownloader =
-        getDashDownloader(
+        getDashDownloader(fakeDataSet, new StreamKey(0, 0, 0), new StreamKey(0, 1, 0));
-            fakeDataSet, new RepresentationKey(0, 0, 0), new RepresentationKey(0, 1, 0));
    dashDownloader.download();
    assertCachedData(cache, fakeDataSet);
  }
@@ -159,7 +158,7 @@ public class DashDownloaderTest {
    when(factory.createDataSource()).thenReturn(fakeDataSource);
    DashDownloader dashDownloader =
-        getDashDownloader(factory, new RepresentationKey(0, 0, 0), new RepresentationKey(0, 1, 0));
+        getDashDownloader(factory, new StreamKey(0, 0, 0), new StreamKey(0, 1, 0));
    dashDownloader.download();
    DataSpec[] openedDataSpecs = fakeDataSource.getAndClearOpenedDataSpecs();
@@ -191,7 +190,7 @@ public class DashDownloaderTest {
    when(factory.createDataSource()).thenReturn(fakeDataSource);
    DashDownloader dashDownloader =
-        getDashDownloader(factory, new RepresentationKey(0, 0, 0), new RepresentationKey(1, 0, 0));
+        getDashDownloader(factory, new StreamKey(0, 0, 0), new StreamKey(1, 0, 0));
    dashDownloader.download();
    DataSpec[] openedDataSpecs = fakeDataSource.getAndClearOpenedDataSpecs();
@@ -220,7 +219,7 @@ public class DashDownloaderTest {
            .endData()
            .setRandomData("audio_segment_3", 6);
-    DashDownloader dashDownloader = getDashDownloader(fakeDataSet, new RepresentationKey(0, 0, 0));
+    DashDownloader dashDownloader = getDashDownloader(fakeDataSet, new StreamKey(0, 0, 0));
    try {
      dashDownloader.download();
      fail();
@@ -245,7 +244,7 @@ public class DashDownloaderTest {
            .endData()
            .setRandomData("audio_segment_3", 6);
-    DashDownloader dashDownloader = getDashDownloader(fakeDataSet, new RepresentationKey(0, 0, 0));
+    DashDownloader dashDownloader = getDashDownloader(fakeDataSet, new StreamKey(0, 0, 0));
    assertThat(dashDownloader.getDownloadedBytes()).isEqualTo(0);
    try {
@@ -274,8 +273,7 @@ public class DashDownloaderTest {
            .setRandomData("text_segment_3", 3);
    DashDownloader dashDownloader =
-        getDashDownloader(
+        getDashDownloader(fakeDataSet, new StreamKey(0, 0, 0), new StreamKey(0, 1, 0));
-            fakeDataSet, new RepresentationKey(0, 0, 0), new RepresentationKey(0, 1, 0));
    dashDownloader.download();
    dashDownloader.remove();
    assertCacheEmpty(cache);
@@ -288,7 +286,7 @@ public class DashDownloaderTest {
            .setData(TEST_MPD_URI, TEST_MPD_NO_INDEX)
            .setRandomData("test_segment_1", 4);
-    DashDownloader dashDownloader = getDashDownloader(fakeDataSet, new RepresentationKey(0, 0, 0));
+    DashDownloader dashDownloader = getDashDownloader(fakeDataSet, new StreamKey(0, 0, 0));
    try {
      dashDownloader.download();
      fail();
@@ -299,17 +297,17 @@ public class DashDownloaderTest {
    assertCacheEmpty(cache);
  }
-  private DashDownloader getDashDownloader(FakeDataSet fakeDataSet, RepresentationKey... keys) {
+  private DashDownloader getDashDownloader(FakeDataSet fakeDataSet, StreamKey... keys) {
    return getDashDownloader(new Factory(null).setFakeDataSet(fakeDataSet), keys);
  }
-  private DashDownloader getDashDownloader(Factory factory, RepresentationKey... keys) {
+  private DashDownloader getDashDownloader(Factory factory, StreamKey... keys) {
    return new DashDownloader(
        TEST_MPD_URI, keysList(keys), new DownloaderConstructorHelper(cache, factory));
  }
-  private static ArrayList<RepresentationKey> keysList(RepresentationKey... keys) {
+  private static ArrayList<StreamKey> keysList(StreamKey... keys) {
-    ArrayList<RepresentationKey> keysList = new ArrayList<>();
+    ArrayList<StreamKey> keysList = new ArrayList<>();
    Collections.addAll(keysList, keys);
    return keysList;
  }

--- a/library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DownloadManagerDashTest.java
+++ b/library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DownloadManagerDashTest.java
@@ -27,7 +27,7 @@ import android.os.ConditionVariable;
 import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.offline.DownloadManager;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
-import com.google.android.exoplayer2.source.dash.manifest.RepresentationKey;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.testutil.DummyMainThread;
 import com.google.android.exoplayer2.testutil.FakeDataSet;
 import com.google.android.exoplayer2.testutil.FakeDataSource;
@@ -62,8 +62,8 @@ public class DownloadManagerDashTest {
  private File tempFolder;
  private FakeDataSet fakeDataSet;
  private DownloadManager downloadManager;
-  private RepresentationKey fakeRepresentationKey1;
+  private StreamKey fakeStreamKey1;
-  private RepresentationKey fakeRepresentationKey2;
+  private StreamKey fakeStreamKey2;
  private TestDownloadManagerListener downloadManagerListener;
  private File actionFile;
  private DummyMainThread dummyMainThread;
@@ -88,8 +88,8 @@ public class DownloadManagerDashTest {
            .setRandomData("text_segment_2", 2)
            .setRandomData("text_segment_3", 3);
-    fakeRepresentationKey1 = new RepresentationKey(0, 0, 0);
+    fakeStreamKey1 = new StreamKey(0, 0, 0);
-    fakeRepresentationKey2 = new RepresentationKey(0, 1, 0);
+    fakeStreamKey2 = new StreamKey(0, 1, 0);
    actionFile = new File(tempFolder, "actionFile");
    createDownloadManager();
  }
@@ -133,7 +133,7 @@ public class DownloadManagerDashTest {
          @Override
          public void run() {
            // Setup an Action and immediately release the DM.
-            handleDownloadAction(fakeRepresentationKey1, fakeRepresentationKey2);
+            handleDownloadAction(fakeStreamKey1, fakeStreamKey2);
            downloadManager.release();
          }
        });
@@ -160,15 +160,15 @@ public class DownloadManagerDashTest {
  @Test
  public void testHandleDownloadAction() throws Throwable {
-    handleDownloadAction(fakeRepresentationKey1, fakeRepresentationKey2);
+    handleDownloadAction(fakeStreamKey1, fakeStreamKey2);
    blockUntilTasksCompleteAndThrowAnyDownloadError();
    assertCachedData(cache, fakeDataSet);
  }
  @Test
  public void testHandleMultipleDownloadAction() throws Throwable {
-    handleDownloadAction(fakeRepresentationKey1);
+    handleDownloadAction(fakeStreamKey1);
-    handleDownloadAction(fakeRepresentationKey2);
+    handleDownloadAction(fakeStreamKey2);
    blockUntilTasksCompleteAndThrowAnyDownloadError();
    assertCachedData(cache, fakeDataSet);
  }
@@ -181,13 +181,13 @@ public class DownloadManagerDashTest {
            new Runnable() {
              @Override
              public void run() {
-                handleDownloadAction(fakeRepresentationKey2);
+                handleDownloadAction(fakeStreamKey2);
              }
            })
        .appendReadData(TestUtil.buildTestData(5))
        .endData();
-    handleDownloadAction(fakeRepresentationKey1);
+    handleDownloadAction(fakeStreamKey1);
    blockUntilTasksCompleteAndThrowAnyDownloadError();
    assertCachedData(cache, fakeDataSet);
@@ -195,7 +195,7 @@ public class DownloadManagerDashTest {
  @Test
  public void testHandleRemoveAction() throws Throwable {
-    handleDownloadAction(fakeRepresentationKey1);
+    handleDownloadAction(fakeStreamKey1);
    blockUntilTasksCompleteAndThrowAnyDownloadError();
@@ -210,7 +210,7 @@ public class DownloadManagerDashTest {
  @Ignore
  @Test
  public void testHandleRemoveActionBeforeDownloadFinish() throws Throwable {
-    handleDownloadAction(fakeRepresentationKey1);
+    handleDownloadAction(fakeStreamKey1);
    handleRemoveAction();
    blockUntilTasksCompleteAndThrowAnyDownloadError();
@@ -233,7 +233,7 @@ public class DownloadManagerDashTest {
        .appendReadData(TestUtil.buildTestData(5))
        .endData();
-    handleDownloadAction(fakeRepresentationKey1);
+    handleDownloadAction(fakeStreamKey1);
    assertThat(downloadInProgressCondition.block(ASSERT_TRUE_TIMEOUT)).isTrue();
@@ -248,7 +248,7 @@ public class DownloadManagerDashTest {
    downloadManagerListener.blockUntilTasksCompleteAndThrowAnyDownloadError();
  }
-  private void handleDownloadAction(RepresentationKey... keys) {
+  private void handleDownloadAction(StreamKey... keys) {
    downloadManager.handleAction(newAction(TEST_MPD_URI, false, null, keys));
  }
@@ -280,8 +280,8 @@ public class DownloadManagerDashTest {
  }
  private static DashDownloadAction newAction(
-      Uri uri, boolean isRemoveAction, @Nullable byte[] data, RepresentationKey... keys) {
+      Uri uri, boolean isRemoveAction, @Nullable byte[] data, StreamKey... keys) {
-    ArrayList<RepresentationKey> keysList = new ArrayList<>();
+    ArrayList<StreamKey> keysList = new ArrayList<>();
    Collections.addAll(keysList, keys);
    return new DashDownloadAction(uri, isRemoveAction, data, keysList);
  }

--- a/library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DownloadServiceDashTest.java
+++ b/library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DownloadServiceDashTest.java
@@ -29,9 +29,9 @@ import com.google.android.exoplayer2.offline.DownloadManager;
 import com.google.android.exoplayer2.offline.DownloadManager.TaskState;
 import com.google.android.exoplayer2.offline.DownloadService;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.scheduler.Requirements;
 import com.google.android.exoplayer2.scheduler.Scheduler;
-import com.google.android.exoplayer2.source.dash.manifest.RepresentationKey;
 import com.google.android.exoplayer2.testutil.DummyMainThread;
 import com.google.android.exoplayer2.testutil.FakeDataSet;
 import com.google.android.exoplayer2.testutil.FakeDataSource;
@@ -65,8 +65,8 @@ public class DownloadServiceDashTest {
  private SimpleCache cache;
  private File tempFolder;
  private FakeDataSet fakeDataSet;
-  private RepresentationKey fakeRepresentationKey1;
+  private StreamKey fakeStreamKey1;
-  private RepresentationKey fakeRepresentationKey2;
+  private StreamKey fakeStreamKey2;
  private Context context;
  private DownloadService dashDownloadService;
  private ConditionVariable pauseDownloadCondition;
@@ -108,8 +108,8 @@ public class DownloadServiceDashTest {
            .setRandomData("text_segment_3", 3);
    final DataSource.Factory fakeDataSourceFactory =
        new FakeDataSource.Factory(null).setFakeDataSet(fakeDataSet);
-    fakeRepresentationKey1 = new RepresentationKey(0, 0, 0);
+    fakeStreamKey1 = new StreamKey(0, 0, 0);
-    fakeRepresentationKey2 = new RepresentationKey(0, 1, 0);
+    fakeStreamKey2 = new StreamKey(0, 1, 0);
    dummyMainThread.runOnMainThread(
        new Runnable() {
@@ -180,8 +180,8 @@ public class DownloadServiceDashTest {
  @Ignore // b/78877092
  @Test
  public void testMultipleDownloadAction() throws Throwable {
-    downloadKeys(fakeRepresentationKey1);
+    downloadKeys(fakeStreamKey1);
-    downloadKeys(fakeRepresentationKey2);
+    downloadKeys(fakeStreamKey2);
    downloadManagerListener.blockUntilTasksCompleteAndThrowAnyDownloadError();
@@ -191,7 +191,7 @@ public class DownloadServiceDashTest {
  @Ignore // b/78877092
  @Test
  public void testRemoveAction() throws Throwable {
-    downloadKeys(fakeRepresentationKey1, fakeRepresentationKey2);
+    downloadKeys(fakeStreamKey1, fakeStreamKey2);
    downloadManagerListener.blockUntilTasksCompleteAndThrowAnyDownloadError();
@@ -206,7 +206,7 @@ public class DownloadServiceDashTest {
  @Test
  public void testRemoveBeforeDownloadComplete() throws Throwable {
    pauseDownloadCondition = new ConditionVariable();
-    downloadKeys(fakeRepresentationKey1, fakeRepresentationKey2);
+    downloadKeys(fakeStreamKey1, fakeStreamKey2);
    removeAll();
@@ -219,7 +219,7 @@ public class DownloadServiceDashTest {
    callDownloadServiceOnStart(newAction(TEST_MPD_URI, true, null));
  }
-  private void downloadKeys(RepresentationKey... keys) {
+  private void downloadKeys(StreamKey... keys) {
    callDownloadServiceOnStart(newAction(TEST_MPD_URI, false, null, keys));
  }
@@ -236,8 +236,8 @@ public class DownloadServiceDashTest {
  }
  private static DashDownloadAction newAction(
-      Uri uri, boolean isRemoveAction, @Nullable byte[] data, RepresentationKey... keys) {
+      Uri uri, boolean isRemoveAction, @Nullable byte[] data, StreamKey... keys) {
-    ArrayList<RepresentationKey> keysList = new ArrayList<>();
+    ArrayList<StreamKey> keysList = new ArrayList<>();
    Collections.addAll(keysList, keys);
    return new DashDownloadAction(uri, isRemoveAction, data, keysList);
  }

--- a/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloadAction.java
+++ b/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloadAction.java
@@ -20,31 +20,31 @@ import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.offline.DownloadAction;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
 import com.google.android.exoplayer2.offline.SegmentDownloadAction;
-import com.google.android.exoplayer2.source.hls.playlist.RenditionKey;
+import com.google.android.exoplayer2.offline.StreamKey;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
 import java.util.List;
 /** An action to download or remove downloaded HLS streams. */
-public final class HlsDownloadAction extends SegmentDownloadAction<RenditionKey> {
+public final class HlsDownloadAction extends SegmentDownloadAction {
  private static final String TYPE = "hls";
  private static final int VERSION = 0;
  public static final Deserializer DESERIALIZER =
-      new SegmentDownloadActionDeserializer<RenditionKey>(TYPE, VERSION) {
+      new SegmentDownloadActionDeserializer(TYPE, VERSION) {
        @Override
-        protected RenditionKey readKey(DataInputStream input) throws IOException {
+        protected StreamKey readKey(DataInputStream input) throws IOException {
          int renditionGroup = input.readInt();
          int trackIndex = input.readInt();
-          return new RenditionKey(renditionGroup, trackIndex);
+          return new StreamKey(renditionGroup, trackIndex);
        }
        @Override
        protected DownloadAction createDownloadAction(
-            Uri uri, boolean isRemoveAction, byte[] data, List<RenditionKey> keys) {
+            Uri uri, boolean isRemoveAction, byte[] data, List<StreamKey> keys) {
          return new HlsDownloadAction(uri, isRemoveAction, data, keys);
        }
      };
@@ -57,7 +57,7 @@ public final class HlsDownloadAction extends SegmentDownloadAction<RenditionKey>
   *     {@code removeAction} is true, {@code keys} must empty.
   */
  public HlsDownloadAction(
-      Uri uri, boolean isRemoveAction, @Nullable byte[] data, List<RenditionKey> keys) {
+      Uri uri, boolean isRemoveAction, @Nullable byte[] data, List<StreamKey> keys) {
    super(TYPE, VERSION, uri, isRemoveAction, data, keys);
  }
@@ -67,8 +67,8 @@ public final class HlsDownloadAction extends SegmentDownloadAction<RenditionKey>
  }
  @Override
-  protected void writeKey(DataOutputStream output, RenditionKey key) throws IOException {
+  protected void writeKey(DataOutputStream output, StreamKey key) throws IOException {
-    output.writeInt(key.type);
+    output.writeInt(key.groupIndex);
    output.writeInt(key.trackIndex);
  }

--- a/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloadHelper.java
+++ b/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloadHelper.java
@@ -19,6 +19,7 @@ import android.net.Uri;
 import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.offline.DownloadHelper;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.offline.TrackKey;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
@@ -26,7 +27,6 @@ import com.google.android.exoplayer2.source.hls.playlist.HlsMasterPlaylist;
 import com.google.android.exoplayer2.source.hls.playlist.HlsMediaPlaylist;
 import com.google.android.exoplayer2.source.hls.playlist.HlsPlaylist;
 import com.google.android.exoplayer2.source.hls.playlist.HlsPlaylistParser;
-import com.google.android.exoplayer2.source.hls.playlist.RenditionKey;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.ParsingLoadable;
 import com.google.android.exoplayer2.util.Assertions;
@@ -44,7 +44,7 @@ public final class HlsDownloadHelper extends DownloadHelper {
  private final DataSource.Factory manifestDataSourceFactory;
  private @MonotonicNonNull HlsPlaylist playlist;
-  private int[] renditionTypes;
+  private int[] renditionGroups;
  public HlsDownloadHelper(Uri uri, DataSource.Factory manifestDataSourceFactory) {
    this.uri = uri;
@@ -78,18 +78,18 @@ public final class HlsDownloadHelper extends DownloadHelper {
    // TODO: Generate track groups as in playback. Reverse the mapping in getDownloadAction.
    HlsMasterPlaylist masterPlaylist = (HlsMasterPlaylist) playlist;
    TrackGroup[] trackGroups = new TrackGroup[3];
-    renditionTypes = new int[3];
+    renditionGroups = new int[3];
    int trackGroupIndex = 0;
    if (!masterPlaylist.variants.isEmpty()) {
-      renditionTypes[trackGroupIndex] = RenditionKey.TYPE_VARIANT;
+      renditionGroups[trackGroupIndex] = HlsMasterPlaylist.GROUP_INDEX_VARIANT;
      trackGroups[trackGroupIndex++] = new TrackGroup(toFormats(masterPlaylist.variants));
    }
    if (!masterPlaylist.audios.isEmpty()) {
-      renditionTypes[trackGroupIndex] = RenditionKey.TYPE_AUDIO;
+      renditionGroups[trackGroupIndex] = HlsMasterPlaylist.GROUP_INDEX_AUDIO;
      trackGroups[trackGroupIndex++] = new TrackGroup(toFormats(masterPlaylist.audios));
    }
    if (!masterPlaylist.subtitles.isEmpty()) {
-      renditionTypes[trackGroupIndex] = RenditionKey.TYPE_SUBTITLE;
+      renditionGroups[trackGroupIndex] = HlsMasterPlaylist.GROUP_INDEX_SUBTITLE;
      trackGroups[trackGroupIndex++] = new TrackGroup(toFormats(masterPlaylist.subtitles));
    }
    return new TrackGroupArray(Arrays.copyOf(trackGroups, trackGroupIndex));
@@ -97,15 +97,14 @@ public final class HlsDownloadHelper extends DownloadHelper {
  @Override
  public HlsDownloadAction getDownloadAction(@Nullable byte[] data, List<TrackKey> trackKeys) {
-    Assertions.checkNotNull(renditionTypes);
+    Assertions.checkNotNull(renditionGroups);
    return new HlsDownloadAction(
-        uri, /* isRemoveAction= */ false, data, toRenditionKeys(trackKeys, renditionTypes));
+        uri, /* isRemoveAction= */ false, data, toStreamKeys(trackKeys, renditionGroups));
  }
  @Override
  public HlsDownloadAction getRemoveAction(@Nullable byte[] data) {
-    return new HlsDownloadAction(
+    return new HlsDownloadAction(uri, /* isRemoveAction= */ true, data, Collections.emptyList());
-        uri, /* isRemoveAction= */ true, data, Collections.<RenditionKey>emptyList());
  }
  private static Format[] toFormats(List<HlsMasterPlaylist.HlsUrl> hlsUrls) {
@@ -116,11 +115,11 @@ public final class HlsDownloadHelper extends DownloadHelper {
    return formats;
  }
-  private static List<RenditionKey> toRenditionKeys(List<TrackKey> trackKeys, int[] groups) {
+  private static List<StreamKey> toStreamKeys(List<TrackKey> trackKeys, int[] groups) {
-    List<RenditionKey> representationKeys = new ArrayList<>(trackKeys.size());
+    List<StreamKey> representationKeys = new ArrayList<>(trackKeys.size());
    for (int i = 0; i < trackKeys.size(); i++) {
      TrackKey trackKey = trackKeys.get(i);
-      representationKeys.add(new RenditionKey(groups[trackKey.groupIndex], trackKey.trackIndex));
+      representationKeys.add(new StreamKey(groups[trackKey.groupIndex], trackKey.trackIndex));
    }
    return representationKeys;
  }

--- a/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloader.java
+++ b/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloader.java
@@ -19,12 +19,12 @@ import android.net.Uri;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
 import com.google.android.exoplayer2.offline.SegmentDownloader;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.source.hls.playlist.HlsMasterPlaylist;
 import com.google.android.exoplayer2.source.hls.playlist.HlsMasterPlaylist.HlsUrl;
 import com.google.android.exoplayer2.source.hls.playlist.HlsMediaPlaylist;
 import com.google.android.exoplayer2.source.hls.playlist.HlsPlaylist;
 import com.google.android.exoplayer2.source.hls.playlist.HlsPlaylistParser;
-import com.google.android.exoplayer2.source.hls.playlist.RenditionKey;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.DataSpec;
 import com.google.android.exoplayer2.upstream.ParsingLoadable;
@@ -48,7 +48,7 @@ import java.util.List;
 * HlsDownloader hlsDownloader =
 *     new HlsDownloader(
 *         playlistUri,
- *         Collections.singletonList(new RenditionKey(RenditionKey.TYPE_VARIANT, 0)),
+ *         Collections.singletonList(new StreamKey(HlsMasterPlaylist.GROUP_INDEX_VARIANT, 0)),
 *         constructorHelper);
 * // Perform the download.
 * hlsDownloader.download();
@@ -57,19 +57,17 @@ import java.util.List;
 *     new CacheDataSource(cache, factory.createDataSource(), CacheDataSource.FLAG_BLOCK_ON_CACHE);
 * }</pre>
 */
-public final class HlsDownloader extends SegmentDownloader<HlsPlaylist, RenditionKey> {
+public final class HlsDownloader extends SegmentDownloader<HlsPlaylist> {
  /**
   * @param playlistUri The {@link Uri} of the playlist to be downloaded.
-   * @param renditionKeys Keys defining which renditions in the playlist should be selected for
+   * @param streamKeys Keys defining which renditions in the playlist should be selected for
   *     download. If empty, all renditions are downloaded.
   * @param constructorHelper A {@link DownloaderConstructorHelper} instance.
   */
  public HlsDownloader(
-      Uri playlistUri,
+      Uri playlistUri, List<StreamKey> streamKeys, DownloaderConstructorHelper constructorHelper) {
-      List<RenditionKey> renditionKeys,
+    super(playlistUri, streamKeys, constructorHelper);
-      DownloaderConstructorHelper constructorHelper) {
-    super(playlistUri, renditionKeys, constructorHelper);
  }
  @Override

--- a/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/HlsMasterPlaylist.java
+++ b/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/HlsMasterPlaylist.java
@@ -16,6 +16,7 @@
 package com.google.android.exoplayer2.source.hls.playlist;
 import com.google.android.exoplayer2.Format;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.util.MimeTypes;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -24,6 +25,10 @@ import java.util.List;
 /** Represents an HLS master playlist. */
 public final class HlsMasterPlaylist extends HlsPlaylist {
+  public static final int GROUP_INDEX_VARIANT = 0;
+  public static final int GROUP_INDEX_AUDIO = 1;
+  public static final int GROUP_INDEX_SUBTITLE = 2;
  /**
   * Represents a url in an HLS master playlist.
   */
@@ -108,13 +113,13 @@ public final class HlsMasterPlaylist extends HlsPlaylist {
  }
  @Override
-  public HlsMasterPlaylist copy(List<RenditionKey> renditionKeys) {
+  public HlsMasterPlaylist copy(List<StreamKey> streamKeys) {
    return new HlsMasterPlaylist(
        baseUri,
        tags,
-        copyRenditionsList(variants, RenditionKey.TYPE_VARIANT, renditionKeys),
+        copyRenditionsList(variants, GROUP_INDEX_VARIANT, streamKeys),
-        copyRenditionsList(audios, RenditionKey.TYPE_AUDIO, renditionKeys),
+        copyRenditionsList(audios, GROUP_INDEX_AUDIO, streamKeys),
-        copyRenditionsList(subtitles, RenditionKey.TYPE_SUBTITLE, renditionKeys),
+        copyRenditionsList(subtitles, GROUP_INDEX_SUBTITLE, streamKeys),
        muxedAudioFormat,
        muxedCaptionFormats);
  }
@@ -133,13 +138,13 @@ public final class HlsMasterPlaylist extends HlsPlaylist {
  }
  private static List<HlsUrl> copyRenditionsList(
-      List<HlsUrl> renditions, int renditionType, List<RenditionKey> renditionKeys) {
+      List<HlsUrl> renditions, int groupIndex, List<StreamKey> streamKeys) {
-    List<HlsUrl> copiedRenditions = new ArrayList<>(renditionKeys.size());
+    List<HlsUrl> copiedRenditions = new ArrayList<>(streamKeys.size());
    for (int i = 0; i < renditions.size(); i++) {
      HlsUrl rendition = renditions.get(i);
-      for (int j = 0; j < renditionKeys.size(); j++) {
+      for (int j = 0; j < streamKeys.size(); j++) {
-        RenditionKey renditionKey = renditionKeys.get(j);
+        StreamKey streamKey = streamKeys.get(j);
-        if (renditionKey.type == renditionType && renditionKey.trackIndex == i) {
+        if (streamKey.groupIndex == groupIndex && streamKey.trackIndex == i) {
          copiedRenditions.add(rendition);
          break;
        }

--- a/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/HlsMediaPlaylist.java
+++ b/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/HlsMediaPlaylist.java
@@ -20,6 +20,7 @@ import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.drm.DrmInitData;
+import com.google.android.exoplayer2.offline.StreamKey;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.util.Collections;
@@ -256,7 +257,7 @@ public final class HlsMediaPlaylist extends HlsPlaylist {
  }
  @Override
-  public HlsMediaPlaylist copy(List<RenditionKey> renditionKeys) {
+  public HlsMediaPlaylist copy(List<StreamKey> streamKeys) {
    return this;
  }

--- a/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/HlsPlaylist.java
+++ b/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/HlsPlaylist.java
@@ -20,7 +20,7 @@ import java.util.Collections;
 import java.util.List;
 /** Represents an HLS playlist. */
-public abstract class HlsPlaylist implements FilterableManifest<HlsPlaylist, RenditionKey> {
+public abstract class HlsPlaylist implements FilterableManifest<HlsPlaylist> {
  /**
   * The base uri. Used to resolve relative paths.

--- a/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/RenditionKey.java
+++ b/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/RenditionKey.java
-/*
- * Copyright (C) 2018 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.source.hls.playlist;
-import android.support.annotation.IntDef;
-import android.support.annotation.NonNull;
-import android.support.annotation.Nullable;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
-/** Uniquely identifies a rendition in an {@link HlsMasterPlaylist}. */
-public final class RenditionKey implements Comparable<RenditionKey> {
-  /** Types of rendition. */
-  @Retention(RetentionPolicy.SOURCE)
-  @IntDef({TYPE_VARIANT, TYPE_AUDIO, TYPE_SUBTITLE})
-  public @interface Type {}
-  public static final int TYPE_VARIANT = 0;
-  public static final int TYPE_AUDIO = 1;
-  public static final int TYPE_SUBTITLE = 2;
-  public final @Type int type;
-  public final int trackIndex;
-  public RenditionKey(@Type int type, int trackIndex) {
-    this.type = type;
-    this.trackIndex = trackIndex;
-  }
-  @Override
-  public String toString() {
-    return type + "." + trackIndex;
-  }
-  @Override
-  public boolean equals(@Nullable Object o) {
-    if (this == o) {
-      return true;
-    }
-    if (o == null || getClass() != o.getClass()) {
-      return false;
-    }
-    RenditionKey that = (RenditionKey) o;
-    return type == that.type && trackIndex == that.trackIndex;
-  }
-  @Override
-  public int hashCode() {
-    int result = type;
-    result = 31 * result + trackIndex;
-    return result;
-  }
-  // Comparable implementation.
-  @Override
-  public int compareTo(@NonNull RenditionKey other) {
-    int result = type - other.type;
-    if (result == 0) {
-      result = trackIndex - other.trackIndex;
-    }
-    return result;
-  }
-}
--- a/library/hls/src/test/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloaderTest.java
+++ b/library/hls/src/test/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloaderTest.java
@@ -36,7 +36,8 @@ import static com.google.common.truth.Truth.assertThat;
 import android.net.Uri;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
-import com.google.android.exoplayer2.source.hls.playlist.RenditionKey;
+import com.google.android.exoplayer2.offline.StreamKey;
+import com.google.android.exoplayer2.source.hls.playlist.HlsMasterPlaylist;
 import com.google.android.exoplayer2.testutil.FakeDataSet;
 import com.google.android.exoplayer2.testutil.FakeDataSource.Factory;
 import com.google.android.exoplayer2.upstream.cache.NoOpCacheEvictor;
@@ -181,17 +182,18 @@ public class HlsDownloaderTest {
    assertCachedData(cache, fakeDataSet);
  }
-  private HlsDownloader getHlsDownloader(String mediaPlaylistUri, List<RenditionKey> keys) {
+  private HlsDownloader getHlsDownloader(String mediaPlaylistUri, List<StreamKey> keys) {
    Factory factory = new Factory(null).setFakeDataSet(fakeDataSet);
    return new HlsDownloader(
        Uri.parse(mediaPlaylistUri), keys, new DownloaderConstructorHelper(cache, factory));
  }
-  private static ArrayList<RenditionKey> getKeys(int... variantIndices) {
+  private static ArrayList<StreamKey> getKeys(int... variantIndices) {
-    ArrayList<RenditionKey> renditionKeys = new ArrayList<>();
+    ArrayList<StreamKey> streamKeys = new ArrayList<>();
    for (int variantIndex : variantIndices) {
-      renditionKeys.add(new RenditionKey(RenditionKey.TYPE_VARIANT, variantIndex));
+      final int trackIndex = variantIndex;
+      streamKeys.add(new StreamKey(HlsMasterPlaylist.GROUP_INDEX_VARIANT, trackIndex));
    }
-    return renditionKeys;
+    return streamKeys;
  }
 }
--- a/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/manifest/SsManifest.java
+++ b/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/manifest/SsManifest.java
@@ -19,6 +19,7 @@ import android.net.Uri;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.offline.FilterableManifest;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.UriUtil;
 import com.google.android.exoplayer2.util.Util;
@@ -33,7 +34,7 @@ import java.util.UUID;
 * @see <a href="http://msdn.microsoft.com/en-us/library/ee673436(v=vs.90).aspx">IIS Smooth
 *     Streaming Client Manifest Format</a>
 */
-public class SsManifest implements FilterableManifest<SsManifest, StreamKey> {
+public class SsManifest implements FilterableManifest<SsManifest> {
  public static final int UNSET_LOOKAHEAD = -1;
@@ -130,7 +131,7 @@ public class SsManifest implements FilterableManifest<SsManifest, StreamKey> {
    List<Format> copiedFormats = new ArrayList<>();
    for (int i = 0; i < sortedKeys.size(); i++) {
      StreamKey key = sortedKeys.get(i);
-      StreamElement streamElement = streamElements[key.streamElementIndex];
+      StreamElement streamElement = streamElements[key.groupIndex];
      if (streamElement != currentStreamElement && currentStreamElement != null) {
        // We're advancing to a new stream element. Add the current one.
        copiedStreamElements.add(currentStreamElement.copy(copiedFormats.toArray(new Format[0])));

--- a/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloadAction.java
+++ b/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloadAction.java
@@ -20,24 +20,26 @@ import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.offline.DownloadAction;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
 import com.google.android.exoplayer2.offline.SegmentDownloadAction;
-import com.google.android.exoplayer2.source.smoothstreaming.manifest.StreamKey;
+import com.google.android.exoplayer2.offline.StreamKey;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
 import java.util.List;
 /** An action to download or remove downloaded SmoothStreaming streams. */
-public final class SsDownloadAction extends SegmentDownloadAction<StreamKey> {
+public final class SsDownloadAction extends SegmentDownloadAction {
  private static final String TYPE = "ss";
  private static final int VERSION = 0;
  public static final Deserializer DESERIALIZER =
-      new SegmentDownloadActionDeserializer<StreamKey>(TYPE, VERSION) {
+      new SegmentDownloadActionDeserializer(TYPE, VERSION) {
        @Override
        protected StreamKey readKey(DataInputStream input) throws IOException {
-          return new StreamKey(input.readInt(), input.readInt());
+          int groupIndex = input.readInt();
+          int trackIndex = input.readInt();
+          return new StreamKey(groupIndex, trackIndex);
        }
        @Override
@@ -66,7 +68,7 @@ public final class SsDownloadAction extends SegmentDownloadAction<StreamKey> {
  @Override
  protected void writeKey(DataOutputStream output, StreamKey key) throws IOException {
-    output.writeInt(key.streamElementIndex);
+    output.writeInt(key.groupIndex);
    output.writeInt(key.trackIndex);
  }

--- a/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloadHelper.java
+++ b/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloadHelper.java
@@ -18,12 +18,12 @@ package com.google.android.exoplayer2.source.smoothstreaming.offline;
 import android.net.Uri;
 import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.offline.DownloadHelper;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.offline.TrackKey;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
 import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsManifest;
 import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsManifestParser;
-import com.google.android.exoplayer2.source.smoothstreaming.manifest.StreamKey;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.ParsingLoadable;
 import com.google.android.exoplayer2.util.Assertions;
@@ -82,8 +82,7 @@ public final class SsDownloadHelper extends DownloadHelper {
  @Override
  public SsDownloadAction getRemoveAction(@Nullable byte[] data) {
-    return new SsDownloadAction(
+    return new SsDownloadAction(uri, /* isRemoveAction= */ true, data, Collections.emptyList());
-        uri, /* isRemoveAction= */ true, data, Collections.<StreamKey>emptyList());
  }
  private static List<StreamKey> toStreamKeys(List<TrackKey> trackKeys) {

--- a/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloader.java
+++ b/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloader.java
@@ -19,11 +19,11 @@ import android.net.Uri;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
 import com.google.android.exoplayer2.offline.SegmentDownloader;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsManifest;
 import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsManifest.StreamElement;
 import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsManifestParser;
 import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsUtil;
-import com.google.android.exoplayer2.source.smoothstreaming.manifest.StreamKey;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.DataSpec;
 import com.google.android.exoplayer2.upstream.ParsingLoadable;
@@ -54,7 +54,7 @@ import java.util.List;
 *     new CacheDataSource(cache, factory.createDataSource(), CacheDataSource.FLAG_BLOCK_ON_CACHE);
 * }</pre>
 */
-public final class SsDownloader extends SegmentDownloader<SsManifest, StreamKey> {
+public final class SsDownloader extends SegmentDownloader<SsManifest> {
  /**
   * @param manifestUri The {@link Uri} of the manifest to be downloaded.

--- a/library/smoothstreaming/src/test/java/com/google/android/exoplayer2/source/smoothstreaming/manifest/SsManifestTest.java
+++ b/library/smoothstreaming/src/test/java/com/google/android/exoplayer2/source/smoothstreaming/manifest/SsManifestTest.java
@@ -19,6 +19,7 @@ import static com.google.common.truth.Truth.assertThat;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsManifest.ProtectionElement;
 import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsManifest.StreamElement;
 import com.google.android.exoplayer2.util.MimeTypes;

--- a/playbacktests/src/androidTest/java/com/google/android/exoplayer2/playbacktests/gts/DashDownloadTest.java
+++ b/playbacktests/src/androidTest/java/com/google/android/exoplayer2/playbacktests/gts/DashDownloadTest.java
@@ -20,11 +20,11 @@ import static com.google.common.truth.Truth.assertWithMessage;
 import android.net.Uri;
 import android.test.ActivityInstrumentationTestCase2;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.source.dash.DashUtil;
 import com.google.android.exoplayer2.source.dash.manifest.AdaptationSet;
 import com.google.android.exoplayer2.source.dash.manifest.DashManifest;
 import com.google.android.exoplayer2.source.dash.manifest.Representation;
-import com.google.android.exoplayer2.source.dash.manifest.RepresentationKey;
 import com.google.android.exoplayer2.source.dash.offline.DashDownloader;
 import com.google.android.exoplayer2.testutil.HostActivity;
 import com.google.android.exoplayer2.upstream.DefaultHttpDataSourceFactory;
@@ -106,7 +106,7 @@ public final class DashDownloadTest extends ActivityInstrumentationTestCase2<Hos
  private DashDownloader downloadContent() throws Exception {
    DashManifest dashManifest =
        DashUtil.loadManifest(httpDataSourceFactory.createDataSource(), MANIFEST_URI);
-    ArrayList<RepresentationKey> keys = new ArrayList<>();
+    ArrayList<StreamKey> keys = new ArrayList<>();
    for (int pIndex = 0; pIndex < dashManifest.getPeriodCount(); pIndex++) {
      List<AdaptationSet> adaptationSets = dashManifest.getPeriod(pIndex).adaptationSets;
      for (int aIndex = 0; aIndex < adaptationSets.size(); aIndex++) {
@@ -116,7 +116,7 @@ public final class DashDownloadTest extends ActivityInstrumentationTestCase2<Hos
          String id = representations.get(rIndex).format.id;
          if (DashTestData.AAC_AUDIO_REPRESENTATION_ID.equals(id)
              || DashTestData.H264_CDD_FIXED.equals(id)) {
-            keys.add(new RepresentationKey(pIndex, aIndex, rIndex));
+            keys.add(new StreamKey(pIndex, aIndex, rIndex));
          }
        }
      }