Add SmoothStreaming downloader and download action

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=165305815

library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloadAction.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.smoothstreaming.offline;
+
+import android.net.Uri;
+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.TrackKey;
+import com.google.android.exoplayer2.util.ClosedSource;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+/** An action to download or remove downloaded SmoothStreaming streams. */
+@ClosedSource(reason = "Not ready yet")
+public final class SsDownloadAction extends SegmentDownloadAction<TrackKey> {
+
+  public static final Serializer SERIALIZER = new SegmentDownloadActionSerializer<TrackKey>() {
+
+    private static final String TYPE = "SsDownloadAction";
+
+    @Override
+    public String getType() {
+      return TYPE;
+    }
+
+    @Override
+    protected void writeKey(DataOutputStream output, TrackKey key) throws IOException {
+      output.writeInt(key.streamElementIndex);
+      output.writeInt(key.trackIndex);
+    }
+
+    @Override
+    protected TrackKey readKey(DataInputStream input) throws IOException {
+      return new TrackKey(input.readInt(), input.readInt());
+    }
+
+    @Override
+    protected TrackKey[] createKeyArray(int keyCount) {
+      return new TrackKey[keyCount];
+    }
+
+    @Override
+    protected DownloadAction createDownloadAction(Uri manifestUri, boolean removeAction,
+        TrackKey[] keys) {
+      return new SsDownloadAction(manifestUri, removeAction, keys);
+    }
+
+  };
+
+  /** @see SegmentDownloadAction#SegmentDownloadAction(Uri, boolean, Object[]) */
+  public SsDownloadAction(Uri manifestUri, boolean removeAction, TrackKey... keys) {
+    super(manifestUri, removeAction, keys);
+  }
+
+  @Override
+  public SsDownloader createDownloader(DownloaderConstructorHelper constructorHelper)
+      throws IOException {
+    SsDownloader downloader = new SsDownloader(manifestUri, constructorHelper);
+    if (!isRemoveAction()) {
+      downloader.selectRepresentations(keys);
+    }
+    return downloader;
+  }
+
+  @Override
+  public Serializer getSerializer() {
+    return SERIALIZER;
+  }
+
+}

library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloader.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.smoothstreaming.offline;
+
+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.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.TrackKey;
+import com.google.android.exoplayer2.upstream.DataSource;
+import com.google.android.exoplayer2.upstream.DataSpec;
+import com.google.android.exoplayer2.upstream.ParsingLoadable;
+import com.google.android.exoplayer2.util.ClosedSource;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Helper class to download SmoothStreaming streams.
+ *
+ * <p>Except {@link #getTotalSegments()}, {@link #getDownloadedSegments()} and {@link
+ * #getDownloadedBytes()}, this class isn't thread safe.
+ *
+ * <p>Example usage:
+ *
+ * <pre>
+ * {@code
+ * SimpleCache cache = new SimpleCache(downloadFolder, new NoOpCacheEvictor());
+ * DefaultHttpDataSourceFactory factory = new DefaultHttpDataSourceFactory("ExoPlayer", null);
+ * DownloaderConstructorHelper constructorHelper =
+ *     new DownloaderConstructorHelper(cache, factory);
+ * SsDownloader ssDownloader = new SsDownloader(manifestUrl, constructorHelper);
+ * // Select the first track of the first stream element
+ * ssDownloader.selectRepresentations(new TrackKey[] {new TrackKey(0, 0)});
+ * ssDownloader.download(new ProgressListener() {
+ *   @Override
+ *   public void onDownloadProgress(Downloader downloader, float downloadPercentage,
+ *       long downloadedBytes) {
+ *     // Invoked periodically during the download.
+ *   }
+ * });
+ * // Access downloaded data using CacheDataSource
+ * CacheDataSource cacheDataSource =
+ *     new CacheDataSource(cache, factory.createDataSource(), CacheDataSource.FLAG_BLOCK_ON_CACHE);}
+ * </pre>
+ */
+@ClosedSource(reason = "Not ready yet")
+public final class SsDownloader extends SegmentDownloader<SsManifest, TrackKey> {
+
+  /**
+   * @see SegmentDownloader#SegmentDownloader(Uri, DownloaderConstructorHelper)
+   */
+  public SsDownloader(Uri manifestUri, DownloaderConstructorHelper constructorHelper)  {
+    super(manifestUri, constructorHelper);
+  }
+
+  @Override
+  public SsManifest getManifest(DataSource dataSource, Uri uri) throws IOException {
+    DataSpec dataSpec = new DataSpec(uri,
+        DataSpec.FLAG_ALLOW_CACHING_UNKNOWN_LENGTH | DataSpec.FLAG_ALLOW_GZIP);
+    ParsingLoadable<SsManifest> loadable = new ParsingLoadable<>(dataSource, dataSpec,
+        C.DATA_TYPE_MANIFEST, new SsManifestParser());
+    loadable.load();
+    return loadable.getResult();
+  }
+
+  @Override
+  protected List<Segment> getAllSegments(DataSource dataSource, SsManifest manifest,
+      boolean allowIndexLoadErrors) throws InterruptedException, IOException {
+    ArrayList<Segment> segments = new ArrayList<>();
+    for (int i = 0; i < manifest.streamElements.length; i++) {
+      StreamElement streamElement = manifest.streamElements[i];
+      for (int j = 0; j < streamElement.formats.length; j++) {
+        segments.addAll(getSegments(dataSource, manifest, new TrackKey[] {new TrackKey(i, j)},
+            allowIndexLoadErrors));
+      }
+    }
+    return segments;
+  }
+
+  @Override
+  protected List<Segment> getSegments(DataSource dataSource, SsManifest manifest,
+      TrackKey[] keys, boolean allowIndexLoadErrors) throws InterruptedException, IOException {
+    ArrayList<Segment> segments = new ArrayList<>();
+    for (TrackKey key : keys) {
+      StreamElement streamElement = manifest.streamElements[key.streamElementIndex];
+      for (int i = 0; i < streamElement.chunkCount; i++) {
+        segments.add(new Segment(streamElement.getStartTimeUs(i),
+            new DataSpec(streamElement.buildRequestUri(key.trackIndex, i))));
+      }
+    }
+    return segments;
+  }
+
+}