Make NetworkLoadable use an injected HttpDataSource.

Note: I'm fairly confident that NetworkLoadable.Parser implementations can live without the inputEncoding being specified. But not completely 100%... Issue: #311 Issue: #56

Make NetworkLoadable use an injected HttpDataSource.
Note: I'm fairly confident that NetworkLoadable.Parser implementations can live without the inputEncoding being specified. But not completely 100%... Issue: #311 Issue: #56
006986cc · Oliver Woodman · 2ce17b60 · 006986cc · 006986cc · 006986cc
Commit 006986cc authored Feb 25, 2015 by Oliver Woodman
Showing with 92 additions and 87 deletions
demo/src/main/java/com/google/android/exoplayer/demo/player/DashRendererBuilder.java
demo/src/main/java/com/google/android/exoplayer/demo/player/HlsRendererBuilder.java
demo/src/main/java/com/google/android/exoplayer/demo/player/SmoothStreamingRendererBuilder.java
library/src/main/java/com/google/android/exoplayer/dash/mpd/MediaPresentationDescriptionParser.java
library/src/main/java/com/google/android/exoplayer/dash/mpd/UtcTimingElementResolver.java
library/src/main/java/com/google/android/exoplayer/hls/HlsChunkSource.java
library/src/main/java/com/google/android/exoplayer/hls/HlsPlaylistParser.java
library/src/main/java/com/google/android/exoplayer/smoothstreaming/SmoothStreamingManifestParser.java
library/src/main/java/com/google/android/exoplayer/upstream/DataSourceInputStream.java
library/src/main/java/com/google/android/exoplayer/upstream/DefaultHttpDataSource.java
library/src/main/java/com/google/android/exoplayer/upstream/HttpDataSource.java
library/src/main/java/com/google/android/exoplayer/util/NetworkLoadable.java → library/src/main/java/com/google/android/exoplayer/upstream/NetworkLoadable.java
library/src/main/java/com/google/android/exoplayer/upstream/UriDataSource.java
library/src/main/java/com/google/android/exoplayer/util/ManifestFetcher.java
--- a/demo/src/main/java/com/google/android/exoplayer/demo/player/DashRendererBuilder.java
+++ b/demo/src/main/java/com/google/android/exoplayer/demo/player/DashRendererBuilder.java
@@ -52,6 +52,8 @@ import com.google.android.exoplayer.text.webvtt.WebvttParser;
 import com.google.android.exoplayer.upstream.BufferPool;
 import com.google.android.exoplayer.upstream.DataSource;
 import com.google.android.exoplayer.upstream.DefaultBandwidthMeter;
+import com.google.android.exoplayer.upstream.DefaultHttpDataSource;
+import com.google.android.exoplayer.upstream.HttpDataSource;
 import com.google.android.exoplayer.upstream.UriDataSource;
 import com.google.android.exoplayer.util.ManifestFetcher;
 import com.google.android.exoplayer.util.ManifestFetcher.ManifestCallback;
@@ -100,6 +102,7 @@ public class DashRendererBuilder implements RendererBuilder,
  private DemoPlayer player;
  private RendererBuilderCallback callback;
  private ManifestFetcher<MediaPresentationDescription> manifestFetcher;
+  private HttpDataSource manifestDataSource;
  private MediaPresentationDescription manifest;
  private long elapsedRealtimeOffset;
@@ -118,7 +121,9 @@ public class DashRendererBuilder implements RendererBuilder,
    this.player = player;
    this.callback = callback;
    MediaPresentationDescriptionParser parser = new MediaPresentationDescriptionParser();
-    manifestFetcher = new ManifestFetcher<MediaPresentationDescription>(url, userAgent, parser);
+    manifestDataSource = new DefaultHttpDataSource(userAgent, null);
+    manifestFetcher = new ManifestFetcher<MediaPresentationDescription>(url, manifestDataSource,
+        parser);
    manifestFetcher.singleLoad(player.getMainHandler().getLooper(), this);
  }
@@ -126,7 +131,7 @@ public class DashRendererBuilder implements RendererBuilder,
  public void onSingleManifest(MediaPresentationDescription manifest) {
    this.manifest = manifest;
    if (manifest.dynamic && manifest.utcTiming != null) {
-      UtcTimingElementResolver.resolveTimingElement(userAgent, manifest.utcTiming,
+      UtcTimingElementResolver.resolveTimingElement(manifestDataSource, manifest.utcTiming,
          manifestFetcher.getManifestLoadTimestamp(), this);
    } else {
      buildRenderers();

--- a/demo/src/main/java/com/google/android/exoplayer/demo/player/HlsRendererBuilder.java
+++ b/demo/src/main/java/com/google/android/exoplayer/demo/player/HlsRendererBuilder.java
@@ -29,6 +29,7 @@ import com.google.android.exoplayer.metadata.MetadataTrackRenderer;
 import com.google.android.exoplayer.text.eia608.Eia608TrackRenderer;
 import com.google.android.exoplayer.upstream.DataSource;
 import com.google.android.exoplayer.upstream.DefaultBandwidthMeter;
+import com.google.android.exoplayer.upstream.DefaultHttpDataSource;
 import com.google.android.exoplayer.upstream.UriDataSource;
 import com.google.android.exoplayer.util.ManifestFetcher;
 import com.google.android.exoplayer.util.ManifestFetcher.ManifestCallback;
@@ -60,7 +61,7 @@ public class HlsRendererBuilder implements RendererBuilder, ManifestCallback<Hls
    this.callback = callback;
    HlsPlaylistParser parser = new HlsPlaylistParser();
    ManifestFetcher<HlsPlaylist> playlistFetcher =
-        new ManifestFetcher<HlsPlaylist>(url, userAgent, parser);
+        new ManifestFetcher<HlsPlaylist>(url, new DefaultHttpDataSource(userAgent, null), parser);
    playlistFetcher.singleLoad(player.getMainHandler().getLooper(), this);
  }

--- a/demo/src/main/java/com/google/android/exoplayer/demo/player/SmoothStreamingRendererBuilder.java
+++ b/demo/src/main/java/com/google/android/exoplayer/demo/player/SmoothStreamingRendererBuilder.java
@@ -42,6 +42,7 @@ import com.google.android.exoplayer.text.ttml.TtmlParser;
 import com.google.android.exoplayer.upstream.BufferPool;
 import com.google.android.exoplayer.upstream.DataSource;
 import com.google.android.exoplayer.upstream.DefaultBandwidthMeter;
+import com.google.android.exoplayer.upstream.DefaultHttpDataSource;
 import com.google.android.exoplayer.upstream.UriDataSource;
 import com.google.android.exoplayer.util.ManifestFetcher;
 import com.google.android.exoplayer.util.Util;
@@ -90,8 +91,8 @@ public class SmoothStreamingRendererBuilder implements RendererBuilder,
    this.player = player;
    this.callback = callback;
    SmoothStreamingManifestParser parser = new SmoothStreamingManifestParser();
-    manifestFetcher = new ManifestFetcher<SmoothStreamingManifest>(url + "/Manifest", userAgent,
+    manifestFetcher = new ManifestFetcher<SmoothStreamingManifest>(url + "/Manifest",
-        parser);
+        new DefaultHttpDataSource(userAgent, null), parser);
    manifestFetcher.singleLoad(player.getMainHandler().getLooper(), this);
  }

--- a/library/src/main/java/com/google/android/exoplayer/dash/mpd/MediaPresentationDescriptionParser.java
+++ b/library/src/main/java/com/google/android/exoplayer/dash/mpd/MediaPresentationDescriptionParser.java
@@ -21,9 +21,9 @@ import com.google.android.exoplayer.dash.mpd.SegmentBase.SegmentList;
 import com.google.android.exoplayer.dash.mpd.SegmentBase.SegmentTemplate;
 import com.google.android.exoplayer.dash.mpd.SegmentBase.SegmentTimelineElement;
 import com.google.android.exoplayer.dash.mpd.SegmentBase.SingleSegmentBase;
+import com.google.android.exoplayer.upstream.NetworkLoadable;
 import com.google.android.exoplayer.util.Assertions;
 import com.google.android.exoplayer.util.MimeTypes;
-import com.google.android.exoplayer.util.NetworkLoadable;
 import com.google.android.exoplayer.util.Util;
 import android.net.Uri;
@@ -73,11 +73,11 @@ public class MediaPresentationDescriptionParser extends DefaultHandler
  // MPD parsing.
  @Override
-  public MediaPresentationDescription parse(String connectionUrl, InputStream inputStream,
+  public MediaPresentationDescription parse(String connectionUrl, InputStream inputStream)
-      String inputEncoding) throws IOException, ParserException {
+      throws IOException, ParserException {
    try {
      XmlPullParser xpp = xmlParserFactory.newPullParser();
-      xpp.setInput(inputStream, inputEncoding);
+      xpp.setInput(inputStream, null);
      int eventType = xpp.next();
      if (eventType != XmlPullParser.START_TAG || !"MPD".equals(xpp.getName())) {
        throw new ParserException(

--- a/library/src/main/java/com/google/android/exoplayer/dash/mpd/UtcTimingElementResolver.java
+++ b/library/src/main/java/com/google/android/exoplayer/dash/mpd/UtcTimingElementResolver.java
@@ -16,10 +16,11 @@
 package com.google.android.exoplayer.dash.mpd;
 import com.google.android.exoplayer.ParserException;
+import com.google.android.exoplayer.upstream.HttpDataSource;
 import com.google.android.exoplayer.upstream.Loader;
 import com.google.android.exoplayer.upstream.Loader.Loadable;
+import com.google.android.exoplayer.upstream.NetworkLoadable;
 import com.google.android.exoplayer.util.Assertions;
-import com.google.android.exoplayer.util.NetworkLoadable;
 import com.google.android.exoplayer.util.Util;
 import android.os.SystemClock;
@@ -62,7 +63,7 @@ public class UtcTimingElementResolver implements Loader.Callback {
    void onTimestampError(UtcTimingElement utcTiming, IOException e);
  }
-  private final String userAgent;
+  private final HttpDataSource httpDataSource;
  private final UtcTimingElement timingElement;
  private final long timingElementElapsedRealtime;
  private final UtcTimingCallback callback;
@@ -73,22 +74,23 @@ public class UtcTimingElementResolver implements Loader.Callback {
  /**
   * Resolves a {@link UtcTimingElement}.
   *
-   * @param userAgent A user agent to use should network requests be necessary.
+   * @param httpDataSource A source to use should network requests be necessary.
   * @param timingElement The element to resolve.
   * @param timingElementElapsedRealtime The {@link SystemClock#elapsedRealtime()} timestamp at
   *     which the element was obtained. Used if the element contains a timestamp directly.
   * @param callback The callback to invoke on resolution or failure.
   */
-  public static void resolveTimingElement(String userAgent, UtcTimingElement timingElement,
+  public static void resolveTimingElement(HttpDataSource httpDataSource,
-      long timingElementElapsedRealtime, UtcTimingCallback callback) {
+      UtcTimingElement timingElement, long timingElementElapsedRealtime,
-    UtcTimingElementResolver resolver = new UtcTimingElementResolver(userAgent, timingElement,
+      UtcTimingCallback callback) {
+    UtcTimingElementResolver resolver = new UtcTimingElementResolver(httpDataSource, timingElement,
        timingElementElapsedRealtime, callback);
    resolver.resolve();
  }
-  private UtcTimingElementResolver(String userAgent, UtcTimingElement timingElement,
+  private UtcTimingElementResolver(HttpDataSource httpDataSource, UtcTimingElement timingElement,
      long timingElementElapsedRealtime, UtcTimingCallback callback) {
-    this.userAgent = userAgent;
+    this.httpDataSource = httpDataSource;
    this.timingElement = Assertions.checkNotNull(timingElement);
    this.timingElementElapsedRealtime = timingElementElapsedRealtime;
    this.callback = Assertions.checkNotNull(callback);
@@ -121,7 +123,7 @@ public class UtcTimingElementResolver implements Loader.Callback {
  private void resolveHttp(NetworkLoadable.Parser<Long> parser) {
    singleUseLoader = new Loader("utctiming");
-    singleUseLoadable = new NetworkLoadable<Long>(timingElement.value, userAgent, parser);
+    singleUseLoadable = new NetworkLoadable<Long>(timingElement.value, httpDataSource, parser);
    singleUseLoader.startLoading(singleUseLoadable, this);
  }
@@ -150,8 +152,8 @@ public class UtcTimingElementResolver implements Loader.Callback {
  private static class XsDateTimeParser implements NetworkLoadable.Parser<Long> {
    @Override
-    public Long parse(String connectionUrl, InputStream inputStream, String inputEncoding)
+    public Long parse(String connectionUrl, InputStream inputStream) throws ParserException,
-        throws ParserException, IOException {
+        IOException {
      String firstLine = new BufferedReader(new InputStreamReader(inputStream)).readLine();
      try {
        return Util.parseXsDateTime(firstLine);
@@ -165,8 +167,8 @@ public class UtcTimingElementResolver implements Loader.Callback {
  private static class Iso8601Parser implements NetworkLoadable.Parser<Long> {
    @Override
-    public Long parse(String connectionUrl, InputStream inputStream, String inputEncoding)
+    public Long parse(String connectionUrl, InputStream inputStream) throws ParserException,
-        throws ParserException, IOException {
+        IOException {
      String firstLine = new BufferedReader(new InputStreamReader(inputStream)).readLine();
      try {
        // TODO: It may be necessary to handle timestamp offsets from UTC.

--- a/library/src/main/java/com/google/android/exoplayer/hls/HlsChunkSource.java
+++ b/library/src/main/java/com/google/android/exoplayer/hls/HlsChunkSource.java
@@ -558,7 +558,7 @@ public class HlsChunkSource {
    @Override
    protected void consume(byte[] data, int limit) throws IOException {
      HlsPlaylist playlist = playlistParser.parse(playlistUrl,
-          new ByteArrayInputStream(data, 0, limit), null);
+          new ByteArrayInputStream(data, 0, limit));
      Assertions.checkState(playlist.type == HlsPlaylist.TYPE_MEDIA);
      HlsMediaPlaylist mediaPlaylist = (HlsMediaPlaylist) playlist;
      setMediaPlaylist(variantIndex, mediaPlaylist);

--- a/library/src/main/java/com/google/android/exoplayer/hls/HlsPlaylistParser.java
+++ b/library/src/main/java/com/google/android/exoplayer/hls/HlsPlaylistParser.java
@@ -18,7 +18,7 @@ package com.google.android.exoplayer.hls;
 import com.google.android.exoplayer.C;
 import com.google.android.exoplayer.ParserException;
 import com.google.android.exoplayer.hls.HlsMediaPlaylist.Segment;
-import com.google.android.exoplayer.util.NetworkLoadable;
+import com.google.android.exoplayer.upstream.NetworkLoadable;
 import com.google.android.exoplayer.util.Util;
 import android.net.Uri;
@@ -84,11 +84,10 @@ public final class HlsPlaylistParser implements NetworkLoadable.Parser<HlsPlayli
      Pattern.compile(IV_ATTR + "=([^,.*]+)");
  @Override
-  public HlsPlaylist parse(String connectionUrl, InputStream inputStream, String inputEncoding)
+  public HlsPlaylist parse(String connectionUrl, InputStream inputStream)
      throws IOException, ParserException {
    Uri baseUri = Util.parseBaseUri(connectionUrl);
-    BufferedReader reader = new BufferedReader((inputEncoding == null)
+    BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
-        ? new InputStreamReader(inputStream) : new InputStreamReader(inputStream, inputEncoding));
    Queue<String> extraLines = new LinkedList<String>();
    String line;
    try {

--- a/library/src/main/java/com/google/android/exoplayer/smoothstreaming/SmoothStreamingManifestParser.java
+++ b/library/src/main/java/com/google/android/exoplayer/smoothstreaming/SmoothStreamingManifestParser.java
@@ -19,10 +19,10 @@ import com.google.android.exoplayer.ParserException;
 import com.google.android.exoplayer.smoothstreaming.SmoothStreamingManifest.ProtectionElement;
 import com.google.android.exoplayer.smoothstreaming.SmoothStreamingManifest.StreamElement;
 import com.google.android.exoplayer.smoothstreaming.SmoothStreamingManifest.TrackElement;
+import com.google.android.exoplayer.upstream.NetworkLoadable;
 import com.google.android.exoplayer.util.Assertions;
 import com.google.android.exoplayer.util.CodecSpecificDataUtil;
 import com.google.android.exoplayer.util.MimeTypes;
-import com.google.android.exoplayer.util.NetworkLoadable;
 import com.google.android.exoplayer.util.Util;
 import android.net.Uri;
@@ -60,11 +60,11 @@ public class SmoothStreamingManifestParser implements
  }
  @Override
-  public SmoothStreamingManifest parse(String connectionUrl, InputStream inputStream,
+  public SmoothStreamingManifest parse(String connectionUrl, InputStream inputStream)
-      String inputEncoding) throws IOException, ParserException {
+      throws IOException, ParserException {
    try {
      XmlPullParser xmlParser = xmlParserFactory.newPullParser();
-      xmlParser.setInput(inputStream, inputEncoding);
+      xmlParser.setInput(inputStream, null);
      SmoothStreamMediaParser smoothStreamMediaParser = new SmoothStreamMediaParser(null,
          Util.parseBaseUri(connectionUrl));
      return (SmoothStreamingManifest) smoothStreamMediaParser.parse(xmlParser);

--- a/library/src/main/java/com/google/android/exoplayer/upstream/DataSourceInputStream.java
+++ b/library/src/main/java/com/google/android/exoplayer/upstream/DataSourceInputStream.java
@@ -43,6 +43,19 @@ public class DataSourceInputStream extends InputStream {
    singleByteArray = new byte[1];
  }
+  /**
+   * Optional call to open the underlying {@link DataSource}.
+   * <p>
+   * Calling this method does nothing if the {@link DataSource} is already open. Calling this
+   * method is optional, since the read and skip methods will automatically open the underlying
+   * {@link DataSource} if it's not open already.
+   *
+   * @throws IOException If an error occurs opening the {@link DataSource}.
+   */
+  public void open() throws IOException {
+    checkOpened();
+  }
  @Override
  public int read() throws IOException {
    read(singleByteArray);

--- a/library/src/main/java/com/google/android/exoplayer/upstream/DefaultHttpDataSource.java
+++ b/library/src/main/java/com/google/android/exoplayer/upstream/DefaultHttpDataSource.java
--- a/library/src/main/java/com/google/android/exoplayer/upstream/HttpDataSource.java
+++ b/library/src/main/java/com/google/android/exoplayer/upstream/HttpDataSource.java
--- a/library/src/main/java/com/google/android/exoplayer/util/NetworkLoadable.java
+++ b/library/src/main/java/com/google/android/exoplayer/util/NetworkLoadable.java
@@ -13,15 +13,15 @@
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
-package com.google.android.exoplayer.util;
+package com.google.android.exoplayer.upstream;
 import com.google.android.exoplayer.ParserException;
 import com.google.android.exoplayer.upstream.Loader.Loadable;
+import android.net.Uri;
 import java.io.IOException;
 import java.io.InputStream;
-import java.net.URL;
-import java.net.URLConnection;
 /**
 * A {@link Loadable} for loading an object over the network.
@@ -40,21 +40,16 @@ public final class NetworkLoadable<T> implements Loadable {
     *
     * @param connectionUrl The source of the response, after any redirection.
     * @param inputStream An {@link InputStream} from which the response data can be read.
-     * @param inputEncoding The encoding of the data, if available.
     * @return The parsed object.
     * @throws ParserException If an error occurs parsing the data.
     * @throws IOException If an error occurs reading data from the stream.
     */
-    T parse(String connectionUrl, InputStream inputStream, String inputEncoding)
+    T parse(String connectionUrl, InputStream inputStream) throws ParserException, IOException;
-        throws ParserException, IOException;
  }
-  public static final int DEFAULT_TIMEOUT_MILLIS = 10000;
+  private final DataSpec dataSpec;
+  private final HttpDataSource httpDataSource;
-  private final String url;
-  private final String userAgent;
-  private final int timeoutMillis;
  private final Parser<T> parser;
  private volatile T result;
@@ -62,24 +57,13 @@ public final class NetworkLoadable<T> implements Loadable {
  /**
   * @param url The url from which the object should be loaded.
-   * @param userAgent The user agent to use when requesting the object.
+   * @param httpDataSource A {@link HttpDataSource} to use when loading the data.
   * @param parser Parses the object from the network response.
   */
-  public NetworkLoadable(String url, String userAgent, Parser<T> parser) {
+  public NetworkLoadable(String url, HttpDataSource httpDataSource, Parser<T> parser) {
-    this(url, userAgent, DEFAULT_TIMEOUT_MILLIS, parser);
+    this.httpDataSource = httpDataSource;
-  }
-  /**
-   * @param url The url from which the object should be loaded.
-   * @param userAgent The user agent to use when requesting the object.
-   * @param timeoutMillis The desired http timeout in milliseconds.
-   * @param parser Parses the object from the network response.
-   */
-  public NetworkLoadable(String url, String userAgent, int timeoutMillis, Parser<T> parser) {
-    this.url = url;
-    this.userAgent = userAgent;
-    this.timeoutMillis = timeoutMillis;
    this.parser = parser;
+    dataSpec = new DataSpec(Uri.parse(url));
  }
  /**
@@ -103,28 +87,13 @@ public final class NetworkLoadable<T> implements Loadable {
  @Override
  public final void load() throws IOException, InterruptedException {
-    String inputEncoding;
+    DataSourceInputStream inputStream = new DataSourceInputStream(httpDataSource, dataSpec);
-    InputStream inputStream = null;
    try {
-      URLConnection connection = configureConnection(new URL(url));
+      inputStream.open();
-      inputStream = connection.getInputStream();
+      result = parser.parse(httpDataSource.getUrl(), inputStream);
-      inputEncoding = connection.getContentEncoding();
-      result = parser.parse(connection.getURL().toString(), inputStream, inputEncoding);
    } finally {
-      if (inputStream != null) {
      inputStream.close();
    }
  }
-  }
-  private URLConnection configureConnection(URL url) throws IOException {
-    URLConnection connection = url.openConnection();
-    connection.setConnectTimeout(timeoutMillis);
-    connection.setReadTimeout(timeoutMillis);
-    connection.setDoOutput(false);
-    connection.setRequestProperty("User-Agent", userAgent);
-    connection.connect();
-    return connection;
-  }
 }
--- a/library/src/main/java/com/google/android/exoplayer/upstream/UriDataSource.java
+++ b/library/src/main/java/com/google/android/exoplayer/upstream/UriDataSource.java
@@ -37,14 +37,14 @@ public final class UriDataSource implements DataSource {
  /**
   * Constructs a new data source that delegates to a {@link FileDataSource} for file URIs and an
-   * {@link HttpDataSource} for other URIs.
+   * {@link DefaultHttpDataSource} for other URIs.
   *
   * @param userAgent The User-Agent string that should be used when requesting remote data.
   * @param transferListener An optional listener.
   */
  public UriDataSource(String userAgent, TransferListener transferListener) {
    this(new FileDataSource(transferListener),
-        new HttpDataSource(userAgent, null, transferListener));
+        new DefaultHttpDataSource(userAgent, null, transferListener));
  }
  /**

--- a/library/src/main/java/com/google/android/exoplayer/util/ManifestFetcher.java
+++ b/library/src/main/java/com/google/android/exoplayer/util/ManifestFetcher.java
@@ -15,8 +15,10 @@
 */
 package com.google.android.exoplayer.util;
+import com.google.android.exoplayer.upstream.HttpDataSource;
 import com.google.android.exoplayer.upstream.Loader;
 import com.google.android.exoplayer.upstream.Loader.Loadable;
+import com.google.android.exoplayer.upstream.NetworkLoadable;
 import android.os.Handler;
 import android.os.Looper;
@@ -28,6 +30,18 @@ import java.util.concurrent.CancellationException;
 /**
 * Performs both single and repeated loads of media manifests.
+ * <p>
+ * Client code is responsible for ensuring that only one load is taking place at any one time.
+ * Typical usage of this class is as follows:
+ * <ol>
+ * <li>Create an instance.</li>
+ * <li>Obtain an initial manifest by calling {@link #singleLoad(Looper, ManifestCallback)} and
+ *     waiting for the callback to be invoked.</li>
+ * <li>For on-demand playbacks, the loader is no longer required. For live playbacks, the loader
+ *     may be required to periodically refresh the manifest. In this case it is injected into any
+ *     components that require it. These components will call {@link #requestRefresh()} on the
+ *     loader whenever a refresh is required.</li>
+ * </ol>
 *
 * @param <T> The type of manifest.
 */
@@ -70,7 +84,7 @@ public class ManifestFetcher<T> implements Loader.Callback {
  }
  private final NetworkLoadable.Parser<T> parser;
-  private final String userAgent;
+  private final HttpDataSource httpDataSource;
  private final Handler eventHandler;
  private final EventListener eventListener;
@@ -89,26 +103,27 @@ public class ManifestFetcher<T> implements Loader.Callback {
  /**
   * @param manifestUrl The manifest location.
-   * @param userAgent The User-Agent string that should be used.
+   * @param httpDataSource The {@link HttpDataSource} to use when loading the manifest.
   * @param parser A parser to parse the loaded manifest data.
   */
-  public ManifestFetcher(String manifestUrl, String userAgent, NetworkLoadable.Parser<T> parser) {
+  public ManifestFetcher(String manifestUrl, HttpDataSource httpDataSource,
-    this(manifestUrl, userAgent, parser, null, null);
+      NetworkLoadable.Parser<T> parser) {
+    this(manifestUrl, httpDataSource, parser, null, null);
  }
  /**
   * @param manifestUrl The manifest location.
-   * @param userAgent The User-Agent string that should be used.
+   * @param httpDataSource The {@link HttpDataSource} to use when loading the manifest.
   * @param parser A parser to parse the loaded manifest data.
   * @param eventHandler A handler to use when delivering events to {@code eventListener}. May be
   *     null if delivery of events is not required.
   * @param eventListener A listener of events. May be null if delivery of events is not required.
   */
-  public ManifestFetcher(String manifestUrl, String userAgent, NetworkLoadable.Parser<T> parser,
+  public ManifestFetcher(String manifestUrl, HttpDataSource httpDataSource,
-      Handler eventHandler, EventListener eventListener) {
+      NetworkLoadable.Parser<T> parser, Handler eventHandler, EventListener eventListener) {
    this.parser = parser;
    this.manifestUrl = manifestUrl;
-    this.userAgent = userAgent;
+    this.httpDataSource = httpDataSource;
    this.eventHandler = eventHandler;
    this.eventListener = eventListener;
  }
@@ -131,7 +146,7 @@ public class ManifestFetcher<T> implements Loader.Callback {
   */
  public void singleLoad(Looper callbackLooper, final ManifestCallback<T> callback) {
    SingleFetchHelper fetchHelper = new SingleFetchHelper(
-        new NetworkLoadable<T>(manifestUrl, userAgent, parser), callbackLooper, callback);
+        new NetworkLoadable<T>(manifestUrl, httpDataSource, parser), callbackLooper, callback);
    fetchHelper.startLoading();
  }
@@ -204,7 +219,7 @@ public class ManifestFetcher<T> implements Loader.Callback {
      loader = new Loader("manifestLoader");
    }
    if (!loader.isLoading()) {
-      currentLoadable = new NetworkLoadable<T>(manifestUrl, userAgent, parser);
+      currentLoadable = new NetworkLoadable<T>(manifestUrl, httpDataSource, parser);
      loader.startLoading(currentLoadable, this);
      notifyManifestRefreshStarted();
    }