Use default Deserializers if non given to DownloadManager

Also moved shared code to SegmentDownloadAction between its subclasses.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=202294880

RELEASENOTES.md

@@ -37,6 +37,7 @@
   CommentFrame to InternalFrame for frames with gapless metadata in MP4.
 * Allow setting the `Looper`, which is used to access the player, in
   `ExoPlayerFactory` ([#4278](https://github.com/google/ExoPlayer/issues/4278)).
+* Use default Deserializers if non given to DownloadManager.
 * Deprecate `Player.DefaultEventListener` as selective listener overrides can
   be directly made with the `Player.EventListener` interface.
 * Deprecate `DefaultAnalyticsListener` as selective listener overrides can be

demos/main/src/main/java/com/google/android/exoplayer2/demo/DemoApplication.java

@@ -16,13 +16,8 @@
 package com.google.android.exoplayer2.demo;
 
 import android.app.Application;
-import com.google.android.exoplayer2.offline.DownloadAction.Deserializer;
 import com.google.android.exoplayer2.offline.DownloadManager;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
-import com.google.android.exoplayer2.offline.ProgressiveDownloadAction;
-import com.google.android.exoplayer2.source.dash.offline.DashDownloadAction;
-import com.google.android.exoplayer2.source.hls.offline.HlsDownloadAction;
-import com.google.android.exoplayer2.source.smoothstreaming.offline.SsDownloadAction;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.DefaultDataSourceFactory;
 import com.google.android.exoplayer2.upstream.DefaultHttpDataSourceFactory;
@@ -46,13 +41,6 @@ public class DemoApplication extends Application {
   private static final String DOWNLOAD_TRACKER_ACTION_FILE = "tracked_actions";
   private static final String DOWNLOAD_CONTENT_DIRECTORY = "downloads";
   private static final int MAX_SIMULTANEOUS_DOWNLOADS = 2;
-  private static final Deserializer[] DOWNLOAD_DESERIALIZERS =
-      new Deserializer[] {
-        DashDownloadAction.DESERIALIZER,
-        HlsDownloadAction.DESERIALIZER,
-        SsDownloadAction.DESERIALIZER,
-        ProgressiveDownloadAction.DESERIALIZER
-      };
 
   protected String userAgent;
 
@@ -105,14 +93,12 @@ public class DemoApplication extends Application {
               downloaderConstructorHelper,
               MAX_SIMULTANEOUS_DOWNLOADS,
               DownloadManager.DEFAULT_MIN_RETRY_COUNT,
-              new File(getDownloadDirectory(), DOWNLOAD_ACTION_FILE),
-              DOWNLOAD_DESERIALIZERS);
+              new File(getDownloadDirectory(), DOWNLOAD_ACTION_FILE));
       downloadTracker =
           new DownloadTracker(
               /* context= */ this,
               buildDataSourceFactory(/* listener= */ null),
-              new File(getDownloadDirectory(), DOWNLOAD_TRACKER_ACTION_FILE),
-              DOWNLOAD_DESERIALIZERS);
+              new File(getDownloadDirectory(), DOWNLOAD_TRACKER_ACTION_FILE));
       downloadManager.addListener(downloadTracker);
     }
   }

demos/main/src/main/java/com/google/android/exoplayer2/demo/DownloadTracker.java

@@ -36,7 +36,6 @@ 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.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;
@@ -86,7 +85,7 @@ public class DownloadTracker implements DownloadManager.Listener {
       Context context,
       DataSource.Factory dataSourceFactory,
       File actionFile,
-      DownloadAction.Deserializer[] deserializers) {
+      DownloadAction.Deserializer... deserializers) {
     this.context = context.getApplicationContext();
     this.dataSourceFactory = dataSourceFactory;
     this.actionFile = new ActionFile(actionFile);
@@ -96,7 +95,8 @@ public class DownloadTracker implements DownloadManager.Listener {
     HandlerThread actionFileWriteThread = new HandlerThread("DownloadTracker");
     actionFileWriteThread.start();
     actionFileWriteHandler = new Handler(actionFileWriteThread.getLooper());
-    loadTrackedActions(deserializers);
+    loadTrackedActions(
+        deserializers.length > 0 ? deserializers : DownloadAction.getDefaultDeserializers());
   }
 
   public void addListener(Listener listener) {
@@ -116,11 +116,7 @@ public class DownloadTracker implements DownloadManager.Listener {
     if (!trackedDownloadStates.containsKey(uri)) {
       return Collections.emptyList();
     }
-    DownloadAction action = trackedDownloadStates.get(uri);
-    if (action instanceof SegmentDownloadAction) {
-      return ((SegmentDownloadAction) action).keys;
-    }
-    return Collections.emptyList();
+    return trackedDownloadStates.get(uri).getKeys();
   }
 
   public void toggleDownload(Activity activity, String name, Uri uri, String extension) {

library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadAction.java

@@ -17,6 +17,7 @@ package com.google.android.exoplayer2.offline;
 
 import android.net.Uri;
 import android.support.annotation.Nullable;
+import com.google.android.exoplayer2.util.Assertions;
 import java.io.ByteArrayOutputStream;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
@@ -24,6 +25,8 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
 
 /** Contains the necessary parameters for a download or remove action. */
 public abstract class DownloadAction {
@@ -50,6 +53,48 @@ public abstract class DownloadAction {
         throws IOException;
   }
 
+  private static @Nullable Deserializer[] defaultDeserializers;
+
+  /** Returns available default {@link Deserializer}s. */
+  public static synchronized Deserializer[] getDefaultDeserializers() {
+    if (defaultDeserializers != null) {
+      return defaultDeserializers;
+    }
+    Deserializer[] deserializers = new Deserializer[4];
+    int count = 0;
+    deserializers[count++] = ProgressiveDownloadAction.DESERIALIZER;
+    Class<?> clazz;
+    // Full class names used for constructor args so the LINT rule triggers if any of them move.
+    try {
+      // LINT.IfChange
+      clazz = Class.forName("com.google.android.exoplayer2.source.dash.offline.DashDownloadAction");
+      // LINT.ThenChange(../../../../../../../../../dash/proguard-rules.txt)
+      deserializers[count++] = getDeserializer(clazz);
+    } catch (Exception e) {
+      // Do nothing.
+    }
+    try {
+      // LINT.IfChange
+      clazz = Class.forName("com.google.android.exoplayer2.source.hls.offline.HlsDownloadAction");
+      // LINT.ThenChange(../../../../../../../../../hls/proguard-rules.txt)
+      deserializers[count++] = getDeserializer(clazz);
+    } catch (Exception e) {
+      // Do nothing.
+    }
+    try {
+      // LINT.IfChange
+      clazz =
+          Class.forName(
+              "com.google.android.exoplayer2.source.smoothstreaming.offline.SsDownloadAction");
+      // LINT.ThenChange(../../../../../../../../../smoothstreaming/proguard-rules.txt)
+      deserializers[count++] = getDeserializer(clazz);
+    } catch (Exception e) {
+      // Do nothing.
+    }
+    defaultDeserializers = Arrays.copyOf(Assertions.checkNotNull(deserializers), count);
+    return defaultDeserializers;
+  }
+
   /**
    * Deserializes one action that was serialized with {@link #serializeToStream(DownloadAction,
    * OutputStream)} from the {@code input}, using the {@link Deserializer}s that supports the
@@ -132,11 +177,16 @@ public abstract class DownloadAction {
     return uri.equals(other.uri);
   }
 
+  /** Returns keys of tracks to be downloaded. */
+  public List<StreamKey> getKeys() {
+    return Collections.emptyList();
+  }
+
   /** Serializes itself into the {@code output}. */
   protected abstract void writeToStream(DataOutputStream output) throws IOException;
 
   /** Creates a {@link Downloader} with the given parameters. */
-  protected abstract Downloader createDownloader(
+  public abstract Downloader createDownloader(
       DownloaderConstructorHelper downloaderConstructorHelper);
 
   @Override
@@ -160,4 +210,9 @@ public abstract class DownloadAction {
     return result;
   }
 
+  private static Deserializer getDeserializer(Class<?> clazz)
+      throws NoSuchFieldException, IllegalAccessException {
+    Object value = clazz.getDeclaredField("DESERIALIZER").get(null);
+    return (Deserializer) Assertions.checkNotNull(value);
+  }
 }

library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadManager.java

@@ -108,7 +108,8 @@ public final class DownloadManager {
    * @param upstreamDataSourceFactory A {@link DataSource.Factory} for creating data sources for
    *     downloading upstream data.
    * @param actionSaveFile File to save active actions.
-   * @param deserializers Used to deserialize {@link DownloadAction}s.
+   * @param deserializers Used to deserialize {@link DownloadAction}s. If empty, {@link
+   *     DownloadAction#getDefaultDeserializers()} is used instead.
    */
   public DownloadManager(
       Cache cache,
@@ -127,7 +128,8 @@ public final class DownloadManager {
    * @param constructorHelper A {@link DownloaderConstructorHelper} to create {@link Downloader}s
    *     for downloading data.
    * @param actionFile The file in which active actions are saved.
-   * @param deserializers Used to deserialize {@link DownloadAction}s.
+   * @param deserializers Used to deserialize {@link DownloadAction}s. If empty, {@link
+   *     DownloadAction#getDefaultDeserializers()} is used instead.
    */
   public DownloadManager(
       DownloaderConstructorHelper constructorHelper,
@@ -149,7 +151,8 @@ public final class DownloadManager {
    * @param maxSimultaneousDownloads The maximum number of simultaneous download tasks.
    * @param minRetryCount The minimum number of times a task must be retried before failing.
    * @param actionFile The file in which active actions are saved.
-   * @param deserializers Used to deserialize {@link DownloadAction}s.
+   * @param deserializers Used to deserialize {@link DownloadAction}s. If empty, {@link
+   *     DownloadAction#getDefaultDeserializers()} is used instead.
    */
   public DownloadManager(
       DownloaderConstructorHelper constructorHelper,
@@ -157,13 +160,12 @@ public final class DownloadManager {
       int minRetryCount,
       File actionFile,
       Deserializer... deserializers) {
-    Assertions.checkArgument(deserializers.length > 0, "At least one Deserializer is required.");
-
     this.downloaderConstructorHelper = constructorHelper;
     this.maxActiveDownloadTasks = maxSimultaneousDownloads;
     this.minRetryCount = minRetryCount;
     this.actionFile = new ActionFile(actionFile);
-    this.deserializers = deserializers;
+    this.deserializers =
+        deserializers.length > 0 ? deserializers : DownloadAction.getDefaultDeserializers();
     this.downloadsStopped = true;
 
     tasks = new ArrayList<>();

library/core/src/main/java/com/google/android/exoplayer2/offline/ProgressiveDownloadAction.java

@@ -44,7 +44,33 @@ public final class ProgressiveDownloadAction extends DownloadAction {
         }
       };
 
-  public final @Nullable String customCacheKey;
+  private final @Nullable String customCacheKey;
+
+  /**
+   * Creates a progressive stream download action.
+   *
+   * @param uri Uri of the data to be downloaded.
+   * @param data Optional custom data for this action.
+   * @param customCacheKey A custom key that uniquely identifies the original stream. If not null it
+   *     is used for cache indexing.
+   */
+  public static ProgressiveDownloadAction createDownloadAction(
+      Uri uri, @Nullable byte[] data, @Nullable String customCacheKey) {
+    return new ProgressiveDownloadAction(uri, /* isRemoveAction= */ false, data, customCacheKey);
+  }
+
+  /**
+   * Creates a progressive stream remove action.
+   *
+   * @param uri Uri of the data to be removed.
+   * @param data Optional custom data for this action.
+   * @param customCacheKey A custom key that uniquely identifies the original stream. If not null it
+   *     is used for cache indexing.
+   */
+  public static ProgressiveDownloadAction createRemoveAction(
+      Uri uri, @Nullable byte[] data, @Nullable String customCacheKey) {
+    return new ProgressiveDownloadAction(uri, /* isRemoveAction= */ true, data, customCacheKey);
+  }
 
   /**
    * @param uri Uri of the data to be downloaded.
@@ -52,7 +78,10 @@ public final class ProgressiveDownloadAction extends DownloadAction {
    * @param data Optional custom data for this action.
    * @param customCacheKey A custom key that uniquely identifies the original stream. If not null it
    *     is used for cache indexing.
+   * @deprecated Use {@link #createDownloadAction(Uri, byte[], String)} or {@link
+   *     #createRemoveAction(Uri, byte[], String)}.
    */
+  @Deprecated
   public ProgressiveDownloadAction(
       Uri uri, boolean isRemoveAction, @Nullable byte[] data, @Nullable String customCacheKey) {
     super(TYPE, VERSION, uri, isRemoveAction, data);
@@ -60,7 +89,7 @@ public final class ProgressiveDownloadAction extends DownloadAction {
   }
 
   @Override
-  protected ProgressiveDownloader createDownloader(DownloaderConstructorHelper constructorHelper) {
+  public ProgressiveDownloader createDownloader(DownloaderConstructorHelper constructorHelper) {
     return new ProgressiveDownloader(uri, customCacheKey, constructorHelper);
   }
 
@@ -105,4 +134,5 @@ public final class ProgressiveDownloadAction extends DownloadAction {
   private String getCacheKey() {
     return customCacheKey != null ? customCacheKey : CacheUtil.generateKey(uri);
   }
+
 }

library/core/src/main/java/com/google/android/exoplayer2/offline/ProgressiveDownloadHelper.java

@@ -51,12 +51,13 @@ public final class ProgressiveDownloadHelper extends DownloadHelper {
   }
 
   @Override
-  public DownloadAction getDownloadAction(@Nullable byte[] data, List<TrackKey> trackKeys) {
-    return new ProgressiveDownloadAction(uri, false, data, customCacheKey);
+  public ProgressiveDownloadAction getDownloadAction(
+      @Nullable byte[] data, List<TrackKey> trackKeys) {
+    return ProgressiveDownloadAction.createDownloadAction(uri, data, customCacheKey);
   }
 
   @Override
-  public DownloadAction getRemoveAction(@Nullable byte[] data) {
-    return new ProgressiveDownloadAction(uri, true, data, customCacheKey);
+  public ProgressiveDownloadAction getRemoveAction(@Nullable byte[] data) {
+    return ProgressiveDownloadAction.createRemoveAction(uri, data, customCacheKey);
   }
 }

library/core/src/main/java/com/google/android/exoplayer2/offline/SegmentDownloadAction.java

@@ -46,13 +46,18 @@ public abstract class SegmentDownloadAction extends DownloadAction {
       int keyCount = input.readInt();
       List<StreamKey> keys = new ArrayList<>();
       for (int i = 0; i < keyCount; i++) {
-        keys.add(readKey(input));
+        keys.add(readKey(version, input));
       }
       return createDownloadAction(uri, isRemoveAction, data, keys);
     }
 
     /** Deserializes a key from the {@code input}. */
-    protected abstract StreamKey readKey(DataInputStream input) throws IOException;
+    protected StreamKey readKey(int version, DataInputStream input) throws IOException {
+      int periodIndex = input.readInt();
+      int groupIndex = input.readInt();
+      int trackIndex = input.readInt();
+      return new StreamKey(periodIndex, groupIndex, trackIndex);
+    }
 
     /** Returns a {@link DownloadAction}. */
     protected abstract DownloadAction createDownloadAction(
@@ -88,6 +93,11 @@ public abstract class SegmentDownloadAction extends DownloadAction {
     }
   }
 
+  @Override
+  public List<StreamKey> getKeys() {
+    return keys;
+  }
+
   @Override
   public final void writeToStream(DataOutputStream output) throws IOException {
     output.writeUTF(uri.toString());
@@ -100,9 +110,6 @@ public abstract class SegmentDownloadAction extends DownloadAction {
     }
   }
 
-  /** Serializes the {@code key} into the {@code output}. */
-  protected abstract void writeKey(DataOutputStream output, StreamKey key) throws IOException;
-
   @Override
   public boolean equals(@Nullable Object o) {
     if (this == o) {
@@ -122,4 +129,10 @@ public abstract class SegmentDownloadAction extends DownloadAction {
     return result;
   }
 
+  /** Serializes the {@code key} into the {@code output}. */
+  private void writeKey(DataOutputStream output, StreamKey key) throws IOException {
+    output.writeInt(key.periodIndex);
+    output.writeInt(key.groupIndex);
+    output.writeInt(key.trackIndex);
+  }
 }

library/core/src/test/java/com/google/android/exoplayer2/offline/ActionFileTest.java

@@ -33,9 +33,7 @@ import org.junit.runner.RunWith;
 import org.robolectric.RobolectricTestRunner;
 import org.robolectric.RuntimeEnvironment;
 
-/**
- * Unit tests for {@link ProgressiveDownloadAction}.
- */
+/** Unit tests for {@link ActionFile}. */
 @RunWith(RobolectricTestRunner.class)
 public class ActionFileTest {
 
@@ -258,7 +256,7 @@ public class ActionFileTest {
     }
 
     @Override
-    protected Downloader createDownloader(DownloaderConstructorHelper downloaderConstructorHelper) {
+    public Downloader createDownloader(DownloaderConstructorHelper downloaderConstructorHelper) {
       return null;
     }
 

library/core/src/test/java/com/google/android/exoplayer2/offline/DownloadManagerTest.java

@@ -510,7 +510,7 @@ public class DownloadManagerTest {
     }
 
     @Override
-    protected Downloader createDownloader(DownloaderConstructorHelper downloaderConstructorHelper) {
+    public Downloader createDownloader(DownloaderConstructorHelper downloaderConstructorHelper) {
       return downloader;
     }
 

library/core/src/test/java/com/google/android/exoplayer2/offline/ProgressiveDownloadActionTest.java

@@ -32,9 +32,7 @@ import org.mockito.Mockito;
 import org.mockito.MockitoAnnotations;
 import org.robolectric.RobolectricTestRunner;
 
-/**
- * Unit tests for {@link ProgressiveDownloadAction}.
- */
+/** Unit tests for {@link ProgressiveDownloadAction}. */
 @RunWith(RobolectricTestRunner.class)
 public class ProgressiveDownloadActionTest {
 
@@ -49,112 +47,109 @@ public class ProgressiveDownloadActionTest {
 
   @Test
   public void testDownloadActionIsNotRemoveAction() throws Exception {
-    ProgressiveDownloadAction action = new ProgressiveDownloadAction(uri1, false, null, null);
+    DownloadAction action = createDownloadAction(uri1, null);
     assertThat(action.isRemoveAction).isFalse();
   }
 
   @Test
   public void testRemoveActionisRemoveAction() throws Exception {
-    ProgressiveDownloadAction action2 = new ProgressiveDownloadAction(uri1, true, null, null);
+    DownloadAction action2 = createRemoveAction(uri1, null);
     assertThat(action2.isRemoveAction).isTrue();
   }
 
   @Test
   public void testCreateDownloader() throws Exception {
     MockitoAnnotations.initMocks(this);
-    ProgressiveDownloadAction action = new ProgressiveDownloadAction(uri1, false, null, null);
-    DownloaderConstructorHelper constructorHelper = new DownloaderConstructorHelper(
-        Mockito.mock(Cache.class), DummyDataSource.FACTORY);
+    DownloadAction action = createDownloadAction(uri1, null);
+    DownloaderConstructorHelper constructorHelper =
+        new DownloaderConstructorHelper(Mockito.mock(Cache.class), DummyDataSource.FACTORY);
     assertThat(action.createDownloader(constructorHelper)).isNotNull();
   }
 
   @Test
   public void testSameUriCacheKeyDifferentAction_IsSameMedia() throws Exception {
-    ProgressiveDownloadAction action1 = new ProgressiveDownloadAction(uri1, true, null, null);
-    ProgressiveDownloadAction action2 = new ProgressiveDownloadAction(uri1, false, null, null);
+    DownloadAction action1 = createRemoveAction(uri1, null);
+    DownloadAction action2 = createDownloadAction(uri1, null);
     assertSameMedia(action1, action2);
   }
 
   @Test
   public void testNullCacheKeyDifferentUriAction_IsNotSameMedia() throws Exception {
-    ProgressiveDownloadAction action3 = new ProgressiveDownloadAction(uri2, true, null, null);
-    ProgressiveDownloadAction action4 = new ProgressiveDownloadAction(uri1, false, null, null);
+    DownloadAction action3 = createRemoveAction(uri2, null);
+    DownloadAction action4 = createDownloadAction(uri1, null);
     assertNotSameMedia(action3, action4);
   }
 
   @Test
   public void testSameCacheKeyDifferentUriAction_IsSameMedia() throws Exception {
-    ProgressiveDownloadAction action5 = new ProgressiveDownloadAction(uri2, true, null, "key");
-    ProgressiveDownloadAction action6 = new ProgressiveDownloadAction(uri1, false, null, "key");
+    DownloadAction action5 = createRemoveAction(uri2, "key");
+    DownloadAction action6 = createDownloadAction(uri1, "key");
     assertSameMedia(action5, action6);
   }
 
   @Test
   public void testSameUriDifferentCacheKeyAction_IsNotSameMedia() throws Exception {
-    ProgressiveDownloadAction action7 = new ProgressiveDownloadAction(uri1, true, null, "key");
-    ProgressiveDownloadAction action8 = new ProgressiveDownloadAction(uri1, false, null, "key2");
+    DownloadAction action7 = createRemoveAction(uri1, "key");
+    DownloadAction action8 = createDownloadAction(uri1, "key2");
     assertNotSameMedia(action7, action8);
   }
 
   @Test
   public void testSameUriNullCacheKeyAction_IsNotSameMedia() throws Exception {
-    ProgressiveDownloadAction action1 = new ProgressiveDownloadAction(uri1, true, null, "key");
-    ProgressiveDownloadAction action2 = new ProgressiveDownloadAction(uri1, false, null, null);
+    DownloadAction action1 = createRemoveAction(uri1, "key");
+    DownloadAction action2 = createDownloadAction(uri1, null);
     assertNotSameMedia(action1, action2);
   }
 
   @Test
   public void testEquals() throws Exception {
-    ProgressiveDownloadAction action1 = new ProgressiveDownloadAction(uri1, true, null, null);
+    DownloadAction action1 = createRemoveAction(uri1, null);
     assertThat(action1.equals(action1)).isTrue();
 
-    ProgressiveDownloadAction action2 = new ProgressiveDownloadAction(uri1, true, null, null);
-    ProgressiveDownloadAction action3 = new ProgressiveDownloadAction(uri1, true, null, null);
+    DownloadAction action2 = createRemoveAction(uri1, null);
+    DownloadAction action3 = createRemoveAction(uri1, null);
     assertThat(action2.equals(action3)).isTrue();
 
-    ProgressiveDownloadAction action4 = new ProgressiveDownloadAction(uri1, true, null, null);
-    ProgressiveDownloadAction action5 = new ProgressiveDownloadAction(uri1, false, null, null);
+    DownloadAction action4 = createRemoveAction(uri1, null);
+    DownloadAction action5 = createDownloadAction(uri1, null);
     assertThat(action4.equals(action5)).isFalse();
 
-    ProgressiveDownloadAction action6 = new ProgressiveDownloadAction(uri1, true, null, null);
-    ProgressiveDownloadAction action7 = new ProgressiveDownloadAction(uri1, true, null, "key");
+    DownloadAction action6 = createRemoveAction(uri1, null);
+    DownloadAction action7 = createRemoveAction(uri1, "key");
     assertThat(action6.equals(action7)).isFalse();
 
-    ProgressiveDownloadAction action8 = new ProgressiveDownloadAction(uri1, true, null, "key2");
-    ProgressiveDownloadAction action9 = new ProgressiveDownloadAction(uri1, true, null, "key");
+    DownloadAction action8 = createRemoveAction(uri1, "key2");
+    DownloadAction action9 = createRemoveAction(uri1, "key");
     assertThat(action8.equals(action9)).isFalse();
 
-    ProgressiveDownloadAction action10 = new ProgressiveDownloadAction(uri1, true, null, null);
-    ProgressiveDownloadAction action11 = new ProgressiveDownloadAction(uri2, true, null, null);
+    DownloadAction action10 = createRemoveAction(uri1, null);
+    DownloadAction action11 = createRemoveAction(uri2, null);
     assertThat(action10.equals(action11)).isFalse();
   }
 
   @Test
   public void testSerializerGetType() throws Exception {
-    ProgressiveDownloadAction action = new ProgressiveDownloadAction(uri1, false, null, null);
+    DownloadAction action = createDownloadAction(uri1, null);
     assertThat(action.type).isNotNull();
   }
 
   @Test
   public void testSerializerWriteRead() throws Exception {
-    doTestSerializationRoundTrip(new ProgressiveDownloadAction(uri1, false, null, null));
-    doTestSerializationRoundTrip(new ProgressiveDownloadAction(uri2, true, null, "key"));
+    doTestSerializationRoundTrip(createDownloadAction(uri1, null));
+    doTestSerializationRoundTrip(createRemoveAction(uri2, "key"));
   }
 
-  private void assertSameMedia(
-      ProgressiveDownloadAction action1, ProgressiveDownloadAction action2) {
+  private void assertSameMedia(DownloadAction action1, DownloadAction action2) {
     assertThat(action1.isSameMedia(action2)).isTrue();
     assertThat(action2.isSameMedia(action1)).isTrue();
   }
 
-  private void assertNotSameMedia(
-      ProgressiveDownloadAction action1, ProgressiveDownloadAction action2) {
+  private void assertNotSameMedia(DownloadAction action1, DownloadAction action2) {
     assertThat(action1.isSameMedia(action2)).isFalse();
     assertThat(action2.isSameMedia(action1)).isFalse();
   }
 
-  private static void doTestSerializationRoundTrip(ProgressiveDownloadAction action)
-      throws IOException {
+  private static void doTestSerializationRoundTrip(DownloadAction action) throws IOException {
     ByteArrayOutputStream out = new ByteArrayOutputStream();
     DataOutputStream output = new DataOutputStream(out);
     DownloadAction.serializeToStream(action, output);
@@ -168,4 +163,11 @@ public class ProgressiveDownloadActionTest {
     assertThat(action2).isEqualTo(action);
   }
 
+  private static DownloadAction createDownloadAction(Uri uri1, String customCacheKey) {
+    return ProgressiveDownloadAction.createDownloadAction(uri1, null, customCacheKey);
+  }
+
+  private static DownloadAction createRemoveAction(Uri uri1, String customCacheKey) {
+    return ProgressiveDownloadAction.createRemoveAction(uri1, null, customCacheKey);
+  }
 }

library/dash/build.gradle

@@ -26,6 +26,7 @@ android {
     defaultConfig {
         minSdkVersion project.ext.minSdkVersion
         targetSdkVersion project.ext.targetSdkVersion
+        consumerProguardFiles 'proguard-rules.txt'
     }
 
     buildTypes {

library/dash/proguard-rules.txt

@@ -0,0 +1,7 @@
+# Proguard rules specific to the dash module.
+
+# Constructors accessed via reflection in SegmentDownloadAction
+-dontnote com.google.android.exoplayer2.source.dash.offline.DashDownloadAction
+-keepclassmembers class com.google.android.exoplayer2.source.dash.offline.DashDownloadAction {
+  static ** DESERIALIZER;
+}

library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadAction.java

@@ -21,9 +21,7 @@ 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.offline.StreamKey;
-import java.io.DataInputStream;
-import java.io.DataOutputStream;
-import java.io.IOException;
+import java.util.Collections;
 import java.util.List;
 
 /** An action to download or remove downloaded DASH streams. */
@@ -34,15 +32,6 @@ public final class DashDownloadAction extends SegmentDownloadAction {
 
   public static final Deserializer DESERIALIZER =
       new SegmentDownloadActionDeserializer(TYPE, VERSION) {
-
-        @Override
-        protected StreamKey readKey(DataInputStream input) throws IOException {
-          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<StreamKey> keys) {
@@ -50,28 +39,46 @@ public final class DashDownloadAction extends SegmentDownloadAction {
         }
       };
 
+  /**
+   * Creates a DASH download action.
+   *
+   * @param uri The URI of the media to be downloaded.
+   * @param data Optional custom data for this action. If {@code null} an empty array will be used.
+   * @param keys Keys of tracks to be downloaded. If empty, all tracks will be downloaded.
+   */
+  public static DashDownloadAction createDownloadAction(
+      Uri uri, @Nullable byte[] data, List<StreamKey> keys) {
+    return new DashDownloadAction(uri, /* isRemoveAction= */ false, data, keys);
+  }
+
+  /**
+   * Creates a DASH remove action.
+   *
+   * @param uri The URI of the media to be removed.
+   * @param data Optional custom data for this action. If {@code null} an empty array will be used.
+   */
+  public static DashDownloadAction createRemoveAction(Uri uri, @Nullable byte[] data) {
+    return new DashDownloadAction(uri, /* isRemoveAction= */ true, data, Collections.emptyList());
+  }
+
   /**
    * @param uri The DASH manifest URI.
    * @param isRemoveAction Whether the data will be removed. If {@code false} it will be downloaded.
    * @param data Optional custom data for this action.
    * @param keys Keys of representations to be downloaded. If empty, all representations are
    *     downloaded. If {@code removeAction} is true, {@code keys} must be empty.
+   * @deprecated Use {@link #createDownloadAction(Uri, byte[], List)} or {@link
+   *     #createRemoveAction(Uri, byte[])}.
    */
+  @Deprecated
   public DashDownloadAction(
       Uri uri, boolean isRemoveAction, @Nullable byte[] data, List<StreamKey> keys) {
     super(TYPE, VERSION, uri, isRemoveAction, data, keys);
   }
 
   @Override
-  protected DashDownloader createDownloader(DownloaderConstructorHelper constructorHelper) {
+  public DashDownloader createDownloader(DownloaderConstructorHelper constructorHelper) {
     return new DashDownloader(uri, keys, constructorHelper);
   }
 
-  @Override
-  protected void writeKey(DataOutputStream output, StreamKey key) throws IOException {
-    output.writeInt(key.periodIndex);
-    output.writeInt(key.groupIndex);
-    output.writeInt(key.trackIndex);
-  }
-
 }

library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadHelper.java

@@ -33,7 +33,6 @@ import com.google.android.exoplayer2.upstream.ParsingLoadable;
 import com.google.android.exoplayer2.util.Assertions;
 import java.io.IOException;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 
@@ -88,12 +87,12 @@ public final class DashDownloadHelper extends DownloadHelper {
 
   @Override
   public DashDownloadAction getDownloadAction(@Nullable byte[] data, List<TrackKey> trackKeys) {
-    return new DashDownloadAction(uri, /* isRemoveAction= */ false, data, toStreamKeys(trackKeys));
+    return DashDownloadAction.createDownloadAction(uri, data, toStreamKeys(trackKeys));
   }
 
   @Override
   public DashDownloadAction getRemoveAction(@Nullable byte[] data) {
-    return new DashDownloadAction(uri, /* isRemoveAction= */ true, data, Collections.emptyList());
+    return DashDownloadAction.createRemoveAction(uri, data);
   }
 
   private static List<StreamKey> toStreamKeys(List<TrackKey> trackKeys) {

library/dash/src/main/proguard-rules.txt

@@ -0,0 +1,7 @@
+# Proguard rules specific to the dash module.
+
+# Constructors accessed via reflection in SegmentDownloadAction
+-dontnote com.google.android.exoplayer2.source.dash.offline.DashDownloadAction
+-keepclassmembers class com.google.android.exoplayer2.source.dash.offline.DashDownloadAction {
+  static ** DESERIALIZER;
+}

library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadActionTest.java

@@ -18,7 +18,6 @@ package com.google.android.exoplayer2.source.dash.offline;
 import static com.google.common.truth.Truth.assertThat;
 
 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.offline.StreamKey;
@@ -38,9 +37,7 @@ import org.mockito.Mockito;
 import org.mockito.MockitoAnnotations;
 import org.robolectric.RobolectricTestRunner;
 
-/**
- * Unit tests for {@link DashDownloadAction}.
- */
+/** Unit tests for {@link DashDownloadAction}. */
 @RunWith(RobolectricTestRunner.class)
 public class DashDownloadActionTest {
 
@@ -55,130 +52,106 @@ public class DashDownloadActionTest {
 
   @Test
   public void testDownloadActionIsNotRemoveAction() {
-    DashDownloadAction action = newAction(uri1, /* isRemoveAction= */ false, /* data= */ null);
+    DownloadAction action = createDownloadAction(uri1);
     assertThat(action.isRemoveAction).isFalse();
   }
 
   @Test
-  public void testRemoveActionisRemoveAction() {
-    DashDownloadAction action2 = newAction(uri1, /* isRemoveAction= */ true, /* data= */ null);
+  public void testRemoveActionIsRemoveAction() {
+    DownloadAction action2 = createRemoveAction(uri1);
     assertThat(action2.isRemoveAction).isTrue();
   }
 
   @Test
   public void testCreateDownloader() {
     MockitoAnnotations.initMocks(this);
-    DashDownloadAction action = newAction(uri1, /* isRemoveAction= */ false, /* data= */ null);
-    DownloaderConstructorHelper constructorHelper = new DownloaderConstructorHelper(
-        Mockito.mock(Cache.class), DummyDataSource.FACTORY);
+    DownloadAction action = createDownloadAction(uri1);
+    DownloaderConstructorHelper constructorHelper =
+        new DownloaderConstructorHelper(Mockito.mock(Cache.class), DummyDataSource.FACTORY);
     assertThat(action.createDownloader(constructorHelper)).isNotNull();
   }
 
   @Test
   public void testSameUriDifferentAction_IsSameMedia() {
-    DashDownloadAction action1 = newAction(uri1, /* isRemoveAction= */ true, /* data= */ null);
-    DashDownloadAction action2 = newAction(uri1, /* isRemoveAction= */ false, /* data= */ null);
+    DownloadAction action1 = createRemoveAction(uri1);
+    DownloadAction action2 = createDownloadAction(uri1);
     assertThat(action1.isSameMedia(action2)).isTrue();
   }
 
   @Test
   public void testDifferentUriAndAction_IsNotSameMedia() {
-    DashDownloadAction action3 = newAction(uri2, /* isRemoveAction= */ true, /* data= */ null);
-    DashDownloadAction action4 = newAction(uri1, /* isRemoveAction= */ false, /* data= */ null);
+    DownloadAction action3 = createRemoveAction(uri2);
+    DownloadAction action4 = createDownloadAction(uri1);
     assertThat(action3.isSameMedia(action4)).isFalse();
   }
 
   @SuppressWarnings("EqualsWithItself")
   @Test
   public void testEquals() {
-    DashDownloadAction action1 = newAction(uri1, /* isRemoveAction= */ true, /* data= */ null);
+    DownloadAction action1 = createRemoveAction(uri1);
     assertThat(action1.equals(action1)).isTrue();
 
-    DashDownloadAction action2 = newAction(uri1, /* isRemoveAction= */ true, /* data= */ null);
-    DashDownloadAction action3 = newAction(uri1, /* isRemoveAction= */ true, /* data= */ null);
+    DownloadAction action2 = createRemoveAction(uri1);
+    DownloadAction action3 = createRemoveAction(uri1);
     assertEqual(action2, action3);
 
-    DashDownloadAction action4 = newAction(uri1, /* isRemoveAction= */ true, /* data= */ null);
-    DashDownloadAction action5 = newAction(uri1, /* isRemoveAction= */ false, /* data= */ null);
+    DownloadAction action4 = createRemoveAction(uri1);
+    DownloadAction action5 = createDownloadAction(uri1);
     assertNotEqual(action4, action5);
 
-    DashDownloadAction action6 = newAction(uri1, /* isRemoveAction= */ false, /* data= */ null);
-    DashDownloadAction action7 =
-        newAction(uri1, /* isRemoveAction= */ false, /* data= */ null, new StreamKey(0, 0, 0));
+    DownloadAction action6 = createDownloadAction(uri1);
+    DownloadAction action7 = createDownloadAction(uri1, new StreamKey(0, 0, 0));
     assertNotEqual(action6, action7);
 
-    DashDownloadAction action8 =
-        newAction(uri1, /* isRemoveAction= */ false, /* data= */ null, new StreamKey(1, 1, 1));
-    DashDownloadAction action9 =
-        newAction(uri1, /* isRemoveAction= */ false, /* data= */ null, new StreamKey(0, 0, 0));
+    DownloadAction action8 = createDownloadAction(uri1, new StreamKey(1, 1, 1));
+    DownloadAction action9 = createDownloadAction(uri1, new StreamKey(0, 0, 0));
     assertNotEqual(action8, action9);
 
-    DashDownloadAction action10 = newAction(uri1, /* isRemoveAction= */ true, /* data= */ null);
-    DashDownloadAction action11 = newAction(uri2, /* isRemoveAction= */ true, /* data= */ null);
+    DownloadAction action10 = createRemoveAction(uri1);
+    DownloadAction action11 = createRemoveAction(uri2);
     assertNotEqual(action10, action11);
 
-    DashDownloadAction action12 =
-        newAction(
-            uri1,
-            /* isRemoveAction= */ false,
-            /* data= */ null,
-            new StreamKey(0, 0, 0),
-            new StreamKey(1, 1, 1));
-    DashDownloadAction action13 =
-        newAction(
-            uri1,
-            /* isRemoveAction= */ false,
-            /* data= */ null,
-            new StreamKey(1, 1, 1),
-            new StreamKey(0, 0, 0));
+    DownloadAction action12 =
+        createDownloadAction(uri1, new StreamKey(0, 0, 0), new StreamKey(1, 1, 1));
+    DownloadAction action13 =
+        createDownloadAction(uri1, new StreamKey(1, 1, 1), new StreamKey(0, 0, 0));
     assertEqual(action12, action13);
 
-    DashDownloadAction action14 =
-        newAction(uri1, /* isRemoveAction= */ false, /* data= */ null, new StreamKey(0, 0, 0));
-    DashDownloadAction action15 =
-        newAction(
-            uri1,
-            /* isRemoveAction= */ false,
-            /* data= */ null,
-            new StreamKey(1, 1, 1),
-            new StreamKey(0, 0, 0));
+    DownloadAction action14 = createDownloadAction(uri1, new StreamKey(0, 0, 0));
+    DownloadAction action15 =
+        createDownloadAction(uri1, new StreamKey(1, 1, 1), new StreamKey(0, 0, 0));
     assertNotEqual(action14, action15);
 
-    DashDownloadAction action16 = newAction(uri1, /* isRemoveAction= */ false, /* data= */ null);
-    DashDownloadAction action17 = newAction(uri1, /* isRemoveAction= */ false, /* data= */ null);
+    DownloadAction action16 = createDownloadAction(uri1);
+    DownloadAction action17 = createDownloadAction(uri1);
     assertEqual(action16, action17);
   }
 
   @Test
   public void testSerializerGetType() {
-    DashDownloadAction action = newAction(uri1, /* isRemoveAction= */ false, /* data= */ null);
+    DownloadAction action = createDownloadAction(uri1);
     assertThat(action.type).isNotNull();
   }
 
   @Test
   public void testSerializerWriteRead() throws Exception {
-    doTestSerializationRoundTrip(newAction(uri1, /* isRemoveAction= */ false, /* data= */ null));
-    doTestSerializationRoundTrip(newAction(uri1, /* isRemoveAction= */ true, /* data= */ null));
+    doTestSerializationRoundTrip(createDownloadAction(uri1));
+    doTestSerializationRoundTrip(createRemoveAction(uri1));
     doTestSerializationRoundTrip(
-        newAction(
-            uri2,
-            /* isRemoveAction= */ false,
-            /* data= */ null,
-            new StreamKey(0, 0, 0),
-            new StreamKey(1, 1, 1)));
+        createDownloadAction(uri2, new StreamKey(0, 0, 0), new StreamKey(1, 1, 1)));
   }
 
-  private static void assertNotEqual(DashDownloadAction action1, DashDownloadAction action2) {
+  private static void assertNotEqual(DownloadAction action1, DownloadAction action2) {
     assertThat(action1).isNotEqualTo(action2);
     assertThat(action2).isNotEqualTo(action1);
   }
 
-  private static void assertEqual(DashDownloadAction action1, DashDownloadAction action2) {
+  private static void assertEqual(DownloadAction action1, DownloadAction action2) {
     assertThat(action1).isEqualTo(action2);
     assertThat(action2).isEqualTo(action1);
   }
 
-  private static void doTestSerializationRoundTrip(DashDownloadAction action) throws IOException {
+  private static void doTestSerializationRoundTrip(DownloadAction action) throws IOException {
     ByteArrayOutputStream out = new ByteArrayOutputStream();
     DataOutputStream output = new DataOutputStream(out);
     DownloadAction.serializeToStream(action, output);
@@ -192,10 +165,13 @@ public class DashDownloadActionTest {
     assertThat(action).isEqualTo(action2);
   }
 
-  private static DashDownloadAction newAction(
-      Uri uri, boolean isRemoveAction, @Nullable byte[] data, StreamKey... keys) {
+  private static DownloadAction createDownloadAction(Uri uri, StreamKey... keys) {
     ArrayList<StreamKey> keysList = new ArrayList<>();
     Collections.addAll(keysList, keys);
-    return new DashDownloadAction(uri, isRemoveAction, data, keysList);
+    return DashDownloadAction.createDownloadAction(uri, null, keysList);
+  }
+
+  private static DownloadAction createRemoveAction(Uri uri) {
+    return DashDownloadAction.createRemoveAction(uri, null);
   }
 }

library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DownloadManagerDashTest.java

@@ -25,6 +25,7 @@ import android.content.Context;
 import android.net.Uri;
 import android.os.ConditionVariable;
 import android.support.annotation.Nullable;
+import com.google.android.exoplayer2.offline.DownloadAction;
 import com.google.android.exoplayer2.offline.DownloadManager;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
 import com.google.android.exoplayer2.offline.StreamKey;
@@ -279,10 +280,16 @@ public class DownloadManagerDashTest {
         });
   }
 
-  private static DashDownloadAction newAction(
+  private static DownloadAction newAction(
       Uri uri, boolean isRemoveAction, @Nullable byte[] data, StreamKey... keys) {
     ArrayList<StreamKey> keysList = new ArrayList<>();
     Collections.addAll(keysList, keys);
-    return new DashDownloadAction(uri, isRemoveAction, data, keysList);
+    DownloadAction result;
+    if (isRemoveAction) {
+      result = DashDownloadAction.createRemoveAction(uri, data);
+    } else {
+      result = DashDownloadAction.createDownloadAction(uri, data, keysList);
+    }
+    return result;
   }
 }

library/dash/src/test/java/com/google/android/exoplayer2/source/dash/offline/DownloadServiceDashTest.java

@@ -25,6 +25,7 @@ import android.content.Context;
 import android.content.Intent;
 import android.net.Uri;
 import android.support.annotation.Nullable;
+import com.google.android.exoplayer2.offline.DownloadAction;
 import com.google.android.exoplayer2.offline.DownloadManager;
 import com.google.android.exoplayer2.offline.DownloadManager.TaskState;
 import com.google.android.exoplayer2.offline.DownloadService;
@@ -216,7 +217,7 @@ public class DownloadServiceDashTest {
     callDownloadServiceOnStart(newAction(TEST_MPD_URI, false, null, keys));
   }
 
-  private void callDownloadServiceOnStart(final DashDownloadAction action) {
+  private void callDownloadServiceOnStart(final DownloadAction action) {
     dummyMainThread.runOnMainThread(
         new Runnable() {
           @Override
@@ -228,10 +229,16 @@ public class DownloadServiceDashTest {
         });
   }
 
-  private static DashDownloadAction newAction(
+  private static DownloadAction newAction(
       Uri uri, boolean isRemoveAction, @Nullable byte[] data, StreamKey... keys) {
     ArrayList<StreamKey> keysList = new ArrayList<>();
     Collections.addAll(keysList, keys);
-    return new DashDownloadAction(uri, isRemoveAction, data, keysList);
+    DownloadAction result;
+    if (isRemoveAction) {
+      result = DashDownloadAction.createRemoveAction(uri, data);
+    } else {
+      result = DashDownloadAction.createDownloadAction(uri, data, keysList);
+    }
+    return result;
   }
 }

library/hls/build.gradle

@@ -26,6 +26,7 @@ android {
     defaultConfig {
         minSdkVersion project.ext.minSdkVersion
         targetSdkVersion project.ext.targetSdkVersion
+        consumerProguardFiles 'proguard-rules.txt'
     }
 
     buildTypes {

library/hls/proguard-rules.txt

@@ -0,0 +1,7 @@
+# Proguard rules specific to the hls module.
+
+# Constructors accessed via reflection in SegmentDownloadAction
+-dontnote com.google.android.exoplayer2.source.hls.offline.HlsDownloadAction
+-keepclassmembers class com.google.android.exoplayer2.source.hls.offline.HlsDownloadAction {
+  static ** DESERIALIZER;
+}

library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloadAction.java

@@ -22,21 +22,24 @@ import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
 import com.google.android.exoplayer2.offline.SegmentDownloadAction;
 import com.google.android.exoplayer2.offline.StreamKey;
 import java.io.DataInputStream;
-import java.io.DataOutputStream;
 import java.io.IOException;
+import java.util.Collections;
 import java.util.List;
 
 /** An action to download or remove downloaded HLS streams. */
 public final class HlsDownloadAction extends SegmentDownloadAction {
 
   private static final String TYPE = "hls";
-  private static final int VERSION = 0;
+  private static final int VERSION = 1;
 
   public static final Deserializer DESERIALIZER =
       new SegmentDownloadActionDeserializer(TYPE, VERSION) {
 
         @Override
-        protected StreamKey readKey(DataInputStream input) throws IOException {
+        protected StreamKey readKey(int version, DataInputStream input) throws IOException {
+          if (version > 0) {
+            return super.readKey(version, input);
+          }
           int renditionGroup = input.readInt();
           int trackIndex = input.readInt();
           return new StreamKey(renditionGroup, trackIndex);
@@ -49,27 +52,46 @@ public final class HlsDownloadAction extends SegmentDownloadAction {
         }
       };
 
+  /**
+   * Creates a HLS download action.
+   *
+   * @param uri The URI of the media to be downloaded.
+   * @param data Optional custom data for this action. If {@code null} an empty array will be used.
+   * @param keys Keys of tracks to be downloaded. If empty, all tracks will be downloaded.
+   */
+  public static HlsDownloadAction createDownloadAction(
+      Uri uri, @Nullable byte[] data, List<StreamKey> keys) {
+    return new HlsDownloadAction(uri, /* isRemoveAction= */ false, data, keys);
+  }
+
+  /**
+   * Creates a HLS remove action.
+   *
+   * @param uri The URI of the media to be removed.
+   * @param data Optional custom data for this action. If {@code null} an empty array will be used.
+   */
+  public static HlsDownloadAction createRemoveAction(Uri uri, @Nullable byte[] data) {
+    return new HlsDownloadAction(uri, /* isRemoveAction= */ true, data, Collections.emptyList());
+  }
+
   /**
    * @param uri The HLS playlist URI.
    * @param isRemoveAction Whether the data will be removed. If {@code false} it will be downloaded.
    * @param data Optional custom data for this action.
    * @param keys Keys of renditions to be downloaded. If empty, all renditions are downloaded. If
    *     {@code removeAction} is true, {@code keys} must empty.
+   * @deprecated Use {@link #createDownloadAction(Uri, byte[], List)} or {@link
+   *     #createRemoveAction(Uri, byte[])}.
    */
+  @Deprecated
   public HlsDownloadAction(
       Uri uri, boolean isRemoveAction, @Nullable byte[] data, List<StreamKey> keys) {
     super(TYPE, VERSION, uri, isRemoveAction, data, keys);
   }
 
   @Override
-  protected HlsDownloader createDownloader(DownloaderConstructorHelper constructorHelper) {
+  public HlsDownloader createDownloader(DownloaderConstructorHelper constructorHelper) {
     return new HlsDownloader(uri, keys, constructorHelper);
   }
 
-  @Override
-  protected void writeKey(DataOutputStream output, StreamKey key) throws IOException {
-    output.writeInt(key.groupIndex);
-    output.writeInt(key.trackIndex);
-  }
-
 }

library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloadHelper.java

@@ -34,7 +34,6 @@ import com.google.android.exoplayer2.util.Assertions;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.List;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 
@@ -100,13 +99,13 @@ public final class HlsDownloadHelper extends DownloadHelper {
   @Override
   public HlsDownloadAction getDownloadAction(@Nullable byte[] data, List<TrackKey> trackKeys) {
     Assertions.checkNotNull(renditionGroups);
-    return new HlsDownloadAction(
-        uri, /* isRemoveAction= */ false, data, toStreamKeys(trackKeys, renditionGroups));
+    return HlsDownloadAction.createDownloadAction(
+        uri, data, toStreamKeys(trackKeys, renditionGroups));
   }
 
   @Override
   public HlsDownloadAction getRemoveAction(@Nullable byte[] data) {
-    return new HlsDownloadAction(uri, /* isRemoveAction= */ true, data, Collections.emptyList());
+    return HlsDownloadAction.createRemoveAction(uri, data);
   }
 
   private static Format[] toFormats(List<HlsMasterPlaylist.HlsUrl> hlsUrls) {

library/hls/src/main/proguard-rules.txt

@@ -0,0 +1,7 @@
+# Proguard rules specific to the hls module.
+
+# Constructors accessed via reflection in SegmentDownloadAction
+-dontnote com.google.android.exoplayer2.source.hls.offline.HlsDownloadAction
+-keepclassmembers class com.google.android.exoplayer2.source.hls.offline.HlsDownloadAction {
+  static ** DESERIALIZER;
+}

library/hls/src/test/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloadActionTest.java

@@ -0,0 +1,205 @@
+/*
+ * 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.offline;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import android.net.Uri;
+import com.google.android.exoplayer2.offline.DownloadAction;
+import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
+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;
+import java.io.ByteArrayOutputStream;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mockito;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.RobolectricTestRunner;
+
+/** Unit tests for {@link HlsDownloadAction}. */
+@RunWith(RobolectricTestRunner.class)
+public class HlsDownloadActionTest {
+
+  private Uri uri1;
+  private Uri uri2;
+
+  @Before
+  public void setUp() {
+    uri1 = Uri.parse("http://test1.uri");
+    uri2 = Uri.parse("http://test2.uri");
+  }
+
+  @Test
+  public void testDownloadActionIsNotRemoveAction() {
+    DownloadAction action = createDownloadAction(uri1);
+    assertThat(action.isRemoveAction).isFalse();
+  }
+
+  @Test
+  public void testRemoveActionIsRemoveAction() {
+    DownloadAction action2 = createRemoveAction(uri1);
+    assertThat(action2.isRemoveAction).isTrue();
+  }
+
+  @Test
+  public void testCreateDownloader() {
+    MockitoAnnotations.initMocks(this);
+    DownloadAction action = createDownloadAction(uri1);
+    DownloaderConstructorHelper constructorHelper =
+        new DownloaderConstructorHelper(Mockito.mock(Cache.class), DummyDataSource.FACTORY);
+    assertThat(action.createDownloader(constructorHelper)).isNotNull();
+  }
+
+  @Test
+  public void testSameUriDifferentAction_IsSameMedia() {
+    DownloadAction action1 = createRemoveAction(uri1);
+    DownloadAction action2 = createDownloadAction(uri1);
+    assertThat(action1.isSameMedia(action2)).isTrue();
+  }
+
+  @Test
+  public void testDifferentUriAndAction_IsNotSameMedia() {
+    DownloadAction action3 = createRemoveAction(uri2);
+    DownloadAction action4 = createDownloadAction(uri1);
+    assertThat(action3.isSameMedia(action4)).isFalse();
+  }
+
+  @SuppressWarnings("EqualsWithItself")
+  @Test
+  public void testEquals() {
+    DownloadAction action1 = createRemoveAction(uri1);
+    assertThat(action1.equals(action1)).isTrue();
+
+    DownloadAction action2 = createRemoveAction(uri1);
+    DownloadAction action3 = createRemoveAction(uri1);
+    assertEqual(action2, action3);
+
+    DownloadAction action4 = createRemoveAction(uri1);
+    DownloadAction action5 = createDownloadAction(uri1);
+    assertNotEqual(action4, action5);
+
+    DownloadAction action6 = createDownloadAction(uri1);
+    DownloadAction action7 = createDownloadAction(uri1, new StreamKey(0, 0));
+    assertNotEqual(action6, action7);
+
+    DownloadAction action8 = createDownloadAction(uri1, new StreamKey(1, 1));
+    DownloadAction action9 = createDownloadAction(uri1, new StreamKey(0, 0));
+    assertNotEqual(action8, action9);
+
+    DownloadAction action10 = createRemoveAction(uri1);
+    DownloadAction action11 = createRemoveAction(uri2);
+    assertNotEqual(action10, action11);
+
+    DownloadAction action12 = createDownloadAction(uri1, new StreamKey(0, 0), new StreamKey(1, 1));
+    DownloadAction action13 = createDownloadAction(uri1, new StreamKey(1, 1), new StreamKey(0, 0));
+    assertEqual(action12, action13);
+
+    DownloadAction action14 = createDownloadAction(uri1, new StreamKey(0, 0));
+    DownloadAction action15 = createDownloadAction(uri1, new StreamKey(1, 1), new StreamKey(0, 0));
+    assertNotEqual(action14, action15);
+
+    DownloadAction action16 = createDownloadAction(uri1);
+    DownloadAction action17 = createDownloadAction(uri1);
+    assertEqual(action16, action17);
+  }
+
+  @Test
+  public void testSerializerGetType() {
+    DownloadAction action = createDownloadAction(uri1);
+    assertThat(action.type).isNotNull();
+  }
+
+  @Test
+  public void testSerializerWriteRead() throws Exception {
+    doTestSerializationRoundTrip(createDownloadAction(uri1));
+    doTestSerializationRoundTrip(createRemoveAction(uri1));
+    doTestSerializationRoundTrip(
+        createDownloadAction(uri2, new StreamKey(0, 0), new StreamKey(1, 1)));
+  }
+
+  @Test
+  public void testSerializerVersion0() throws Exception {
+    doTestSerializationV0RoundTrip(createDownloadAction(uri1));
+    doTestSerializationV0RoundTrip(createRemoveAction(uri1));
+    doTestSerializationV0RoundTrip(
+        createDownloadAction(uri2, new StreamKey(0, 0), new StreamKey(1, 1)));
+  }
+
+  private static void assertNotEqual(DownloadAction action1, DownloadAction action2) {
+    assertThat(action1).isNotEqualTo(action2);
+    assertThat(action2).isNotEqualTo(action1);
+  }
+
+  private static void assertEqual(DownloadAction action1, DownloadAction action2) {
+    assertThat(action1).isEqualTo(action2);
+    assertThat(action2).isEqualTo(action1);
+  }
+
+  private static void doTestSerializationRoundTrip(DownloadAction action) throws IOException {
+    ByteArrayOutputStream out = new ByteArrayOutputStream();
+    DataOutputStream output = new DataOutputStream(out);
+    DownloadAction.serializeToStream(action, output);
+
+    assertEqual(action, deserializeActionFromStream(out));
+  }
+
+  private static void doTestSerializationV0RoundTrip(HlsDownloadAction action) throws IOException {
+    ByteArrayOutputStream out = new ByteArrayOutputStream();
+    DataOutputStream output = new DataOutputStream(out);
+    DataOutputStream dataOutputStream = new DataOutputStream(output);
+    dataOutputStream.writeUTF(action.type);
+    dataOutputStream.writeInt(/* version */ 0);
+    dataOutputStream.writeUTF(action.uri.toString());
+    dataOutputStream.writeBoolean(action.isRemoveAction);
+    dataOutputStream.writeInt(action.data.length);
+    dataOutputStream.write(action.data);
+    dataOutputStream.writeInt(action.keys.size());
+    for (int i = 0; i < action.keys.size(); i++) {
+      StreamKey key = action.keys.get(i);
+      dataOutputStream.writeInt(key.groupIndex);
+      dataOutputStream.writeInt(key.trackIndex);
+    }
+    dataOutputStream.flush();
+
+    assertEqual(action, deserializeActionFromStream(out));
+  }
+
+  private static DownloadAction deserializeActionFromStream(ByteArrayOutputStream out)
+      throws IOException {
+    ByteArrayInputStream in = new ByteArrayInputStream(out.toByteArray());
+    DataInputStream input = new DataInputStream(in);
+    return DownloadAction.deserializeFromStream(
+        new DownloadAction.Deserializer[] {HlsDownloadAction.DESERIALIZER}, input);
+  }
+
+  private static HlsDownloadAction createDownloadAction(Uri uri, StreamKey... keys) {
+    ArrayList<StreamKey> keysList = new ArrayList<>();
+    Collections.addAll(keysList, keys);
+    return HlsDownloadAction.createDownloadAction(uri, null, keysList);
+  }
+
+  private static HlsDownloadAction createRemoveAction(Uri uri) {
+    return HlsDownloadAction.createRemoveAction(uri, null);
+  }
+}

library/smoothstreaming/build.gradle

@@ -26,6 +26,7 @@ android {
     defaultConfig {
         minSdkVersion project.ext.minSdkVersion
         targetSdkVersion project.ext.targetSdkVersion
+        consumerProguardFiles 'proguard-rules.txt'
     }
 
     buildTypes {

library/smoothstreaming/proguard-rules.txt

@@ -0,0 +1,7 @@
+# Proguard rules specific to the smoothstreaming module.
+
+# Constructors accessed via reflection in SegmentDownloadAction
+-dontnote com.google.android.exoplayer2.source.smoothstreaming.offline.SsDownloadAction
+-keepclassmembers class com.google.android.exoplayer2.source.smoothstreaming.offline.SsDownloadAction {
+  static ** DESERIALIZER;
+}

library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloadAction.java

@@ -22,21 +22,24 @@ import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
 import com.google.android.exoplayer2.offline.SegmentDownloadAction;
 import com.google.android.exoplayer2.offline.StreamKey;
 import java.io.DataInputStream;
-import java.io.DataOutputStream;
 import java.io.IOException;
+import java.util.Collections;
 import java.util.List;
 
 /** An action to download or remove downloaded SmoothStreaming streams. */
 public final class SsDownloadAction extends SegmentDownloadAction {
 
   private static final String TYPE = "ss";
-  private static final int VERSION = 0;
+  private static final int VERSION = 1;
 
   public static final Deserializer DESERIALIZER =
       new SegmentDownloadActionDeserializer(TYPE, VERSION) {
 
         @Override
-        protected StreamKey readKey(DataInputStream input) throws IOException {
+        protected StreamKey readKey(int version, DataInputStream input) throws IOException {
+          if (version > 0) {
+            return super.readKey(version, input);
+          }
           int groupIndex = input.readInt();
           int trackIndex = input.readInt();
           return new StreamKey(groupIndex, trackIndex);
@@ -49,27 +52,46 @@ public final class SsDownloadAction extends SegmentDownloadAction {
         }
       };
 
+  /**
+   * Creates a SmoothStreaming download action.
+   *
+   * @param uri The URI of the media to be downloaded.
+   * @param data Optional custom data for this action. If {@code null} an empty array will be used.
+   * @param keys Keys of tracks to be downloaded. If empty, all tracks will be downloaded.
+   */
+  public static SsDownloadAction createDownloadAction(
+      Uri uri, @Nullable byte[] data, List<StreamKey> keys) {
+    return new SsDownloadAction(uri, /* isRemoveAction= */ false, data, keys);
+  }
+
+  /**
+   * Creates a SmoothStreaming remove action.
+   *
+   * @param uri The URI of the media to be removed.
+   * @param data Optional custom data for this action. If {@code null} an empty array will be used.
+   */
+  public static SsDownloadAction createRemoveAction(Uri uri, @Nullable byte[] data) {
+    return new SsDownloadAction(uri, /* isRemoveAction= */ true, data, Collections.emptyList());
+  }
+
   /**
    * @param uri The SmoothStreaming manifest URI.
    * @param isRemoveAction Whether the data will be removed. If {@code false} it will be downloaded.
    * @param data Optional custom data for this action.
    * @param keys Keys of streams to be downloaded. If empty, all streams are downloaded. If {@code
    *     removeAction} is true, {@code keys} must be empty.
+   * @deprecated Use {@link #createDownloadAction(Uri, byte[], List)} or {@link
+   *     #createRemoveAction(Uri, byte[])}.
    */
+  @Deprecated
   public SsDownloadAction(
       Uri uri, boolean isRemoveAction, @Nullable byte[] data, List<StreamKey> keys) {
     super(TYPE, VERSION, uri, isRemoveAction, data, keys);
   }
 
   @Override
-  protected SsDownloader createDownloader(DownloaderConstructorHelper constructorHelper) {
+  public SsDownloader createDownloader(DownloaderConstructorHelper constructorHelper) {
     return new SsDownloader(uri, keys, constructorHelper);
   }
 
-  @Override
-  protected void writeKey(DataOutputStream output, StreamKey key) throws IOException {
-    output.writeInt(key.groupIndex);
-    output.writeInt(key.trackIndex);
-  }
-
 }

library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloadHelper.java

@@ -30,7 +30,6 @@ import com.google.android.exoplayer2.upstream.ParsingLoadable;
 import com.google.android.exoplayer2.util.Assertions;
 import java.io.IOException;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 
@@ -78,12 +77,12 @@ public final class SsDownloadHelper extends DownloadHelper {
 
   @Override
   public SsDownloadAction getDownloadAction(@Nullable byte[] data, List<TrackKey> trackKeys) {
-    return new SsDownloadAction(uri, /* isRemoveAction= */ false, data, toStreamKeys(trackKeys));
+    return SsDownloadAction.createDownloadAction(uri, data, toStreamKeys(trackKeys));
   }
 
   @Override
   public SsDownloadAction getRemoveAction(@Nullable byte[] data) {
-    return new SsDownloadAction(uri, /* isRemoveAction= */ true, data, Collections.emptyList());
+    return SsDownloadAction.createRemoveAction(uri, data);
   }
 
   private static List<StreamKey> toStreamKeys(List<TrackKey> trackKeys) {

library/smoothstreaming/src/main/proguard-rules.txt

@@ -0,0 +1,7 @@
+# Proguard rules specific to the smoothstreaming module.
+
+# Constructors accessed via reflection in SegmentDownloadAction
+-dontnote com.google.android.exoplayer2.source.smoothstreaming.offline.SsDownloadAction
+-keepclassmembers class com.google.android.exoplayer2.source.smoothstreaming.offline.SsDownloadAction {
+  static ** DESERIALIZER;
+}

library/smoothstreaming/src/test/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloadActionTest.java

@@ -0,0 +1,205 @@
+/*
+ * 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.smoothstreaming.offline;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import android.net.Uri;
+import com.google.android.exoplayer2.offline.DownloadAction;
+import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
+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;
+import java.io.ByteArrayOutputStream;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mockito;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.RobolectricTestRunner;
+
+/** Unit tests for {@link SsDownloadAction}. */
+@RunWith(RobolectricTestRunner.class)
+public class SsDownloadActionTest {
+
+  private Uri uri1;
+  private Uri uri2;
+
+  @Before
+  public void setUp() {
+    uri1 = Uri.parse("http://test/1.uri");
+    uri2 = Uri.parse("http://test/2.uri");
+  }
+
+  @Test
+  public void testDownloadActionIsNotRemoveAction() {
+    DownloadAction action = createDownloadAction(uri1);
+    assertThat(action.isRemoveAction).isFalse();
+  }
+
+  @Test
+  public void testRemoveActionIsRemoveAction() {
+    DownloadAction action2 = createRemoveAction(uri1);
+    assertThat(action2.isRemoveAction).isTrue();
+  }
+
+  @Test
+  public void testCreateDownloader() {
+    MockitoAnnotations.initMocks(this);
+    DownloadAction action = createDownloadAction(uri1);
+    DownloaderConstructorHelper constructorHelper =
+        new DownloaderConstructorHelper(Mockito.mock(Cache.class), DummyDataSource.FACTORY);
+    assertThat(action.createDownloader(constructorHelper)).isNotNull();
+  }
+
+  @Test
+  public void testSameUriDifferentAction_IsSameMedia() {
+    DownloadAction action1 = createRemoveAction(uri1);
+    DownloadAction action2 = createDownloadAction(uri1);
+    assertThat(action1.isSameMedia(action2)).isTrue();
+  }
+
+  @Test
+  public void testDifferentUriAndAction_IsNotSameMedia() {
+    DownloadAction action3 = createRemoveAction(uri2);
+    DownloadAction action4 = createDownloadAction(uri1);
+    assertThat(action3.isSameMedia(action4)).isFalse();
+  }
+
+  @SuppressWarnings("EqualsWithItself")
+  @Test
+  public void testEquals() {
+    DownloadAction action1 = createRemoveAction(uri1);
+    assertThat(action1.equals(action1)).isTrue();
+
+    DownloadAction action2 = createRemoveAction(uri1);
+    DownloadAction action3 = createRemoveAction(uri1);
+    assertEqual(action2, action3);
+
+    DownloadAction action4 = createRemoveAction(uri1);
+    DownloadAction action5 = createDownloadAction(uri1);
+    assertNotEqual(action4, action5);
+
+    DownloadAction action6 = createDownloadAction(uri1);
+    DownloadAction action7 = createDownloadAction(uri1, new StreamKey(0, 0));
+    assertNotEqual(action6, action7);
+
+    DownloadAction action8 = createDownloadAction(uri1, new StreamKey(1, 1));
+    DownloadAction action9 = createDownloadAction(uri1, new StreamKey(0, 0));
+    assertNotEqual(action8, action9);
+
+    DownloadAction action10 = createRemoveAction(uri1);
+    DownloadAction action11 = createRemoveAction(uri2);
+    assertNotEqual(action10, action11);
+
+    DownloadAction action12 = createDownloadAction(uri1, new StreamKey(0, 0), new StreamKey(1, 1));
+    DownloadAction action13 = createDownloadAction(uri1, new StreamKey(1, 1), new StreamKey(0, 0));
+    assertEqual(action12, action13);
+
+    DownloadAction action14 = createDownloadAction(uri1, new StreamKey(0, 0));
+    DownloadAction action15 = createDownloadAction(uri1, new StreamKey(1, 1), new StreamKey(0, 0));
+    assertNotEqual(action14, action15);
+
+    DownloadAction action16 = createDownloadAction(uri1);
+    DownloadAction action17 = createDownloadAction(uri1);
+    assertEqual(action16, action17);
+  }
+
+  @Test
+  public void testSerializerGetType() {
+    DownloadAction action = createDownloadAction(uri1);
+    assertThat(action.type).isNotNull();
+  }
+
+  @Test
+  public void testSerializerWriteRead() throws Exception {
+    doTestSerializationRoundTrip(createDownloadAction(uri1));
+    doTestSerializationRoundTrip(createRemoveAction(uri1));
+    doTestSerializationRoundTrip(
+        createDownloadAction(uri2, new StreamKey(0, 0), new StreamKey(1, 1)));
+  }
+
+  @Test
+  public void testSerializerVersion0() throws Exception {
+    doTestSerializationV0RoundTrip(createDownloadAction(uri1));
+    doTestSerializationV0RoundTrip(createRemoveAction(uri1));
+    doTestSerializationV0RoundTrip(
+        createDownloadAction(uri2, new StreamKey(0, 0), new StreamKey(1, 1)));
+  }
+
+  private static void assertNotEqual(DownloadAction action1, DownloadAction action2) {
+    assertThat(action1).isNotEqualTo(action2);
+    assertThat(action2).isNotEqualTo(action1);
+  }
+
+  private static void assertEqual(DownloadAction action1, DownloadAction action2) {
+    assertThat(action1).isEqualTo(action2);
+    assertThat(action2).isEqualTo(action1);
+  }
+
+  private static void doTestSerializationRoundTrip(DownloadAction action) throws IOException {
+    ByteArrayOutputStream out = new ByteArrayOutputStream();
+    DataOutputStream output = new DataOutputStream(out);
+    DownloadAction.serializeToStream(action, output);
+
+    assertEqual(action, deserializeActionFromStream(out));
+  }
+
+  private static void doTestSerializationV0RoundTrip(SsDownloadAction action) throws IOException {
+    ByteArrayOutputStream out = new ByteArrayOutputStream();
+    DataOutputStream output = new DataOutputStream(out);
+    DataOutputStream dataOutputStream = new DataOutputStream(output);
+    dataOutputStream.writeUTF(action.type);
+    dataOutputStream.writeInt(/* version */ 0);
+    dataOutputStream.writeUTF(action.uri.toString());
+    dataOutputStream.writeBoolean(action.isRemoveAction);
+    dataOutputStream.writeInt(action.data.length);
+    dataOutputStream.write(action.data);
+    dataOutputStream.writeInt(action.keys.size());
+    for (int i = 0; i < action.keys.size(); i++) {
+      StreamKey key = action.keys.get(i);
+      dataOutputStream.writeInt(key.groupIndex);
+      dataOutputStream.writeInt(key.trackIndex);
+    }
+    dataOutputStream.flush();
+
+    assertEqual(action, deserializeActionFromStream(out));
+  }
+
+  private static DownloadAction deserializeActionFromStream(ByteArrayOutputStream out)
+      throws IOException {
+    ByteArrayInputStream in = new ByteArrayInputStream(out.toByteArray());
+    DataInputStream input = new DataInputStream(in);
+    return DownloadAction.deserializeFromStream(
+        new DownloadAction.Deserializer[] {SsDownloadAction.DESERIALIZER}, input);
+  }
+
+  private static SsDownloadAction createDownloadAction(Uri uri, StreamKey... keys) {
+    ArrayList<StreamKey> keysList = new ArrayList<>();
+    Collections.addAll(keysList, keys);
+    return SsDownloadAction.createDownloadAction(uri, null, keysList);
+  }
+
+  private static SsDownloadAction createRemoveAction(Uri uri) {
+    return SsDownloadAction.createRemoveAction(uri, null);
+  }
+}