class DownloadHelper {

  @Nullable
  public Object getManifest() {
    if (mediaSource == null) {
      return null;
    }
    assertPreparedWithMedia();
    return mediaPreparer.manifest;
  }

  public  DownloadHelper(
      String downloadType,
      Uri uri,
      @Nullable String cacheKey,
      @Nullable MediaSource mediaSource,
      DefaultTrackSelector.Parameters trackSelectorParameters,
      RendererCapabilities[] rendererCapabilities);

}