Add SampleSourceProvider as a factory for SampleSources (playlists #2).

Initially only the first source index is used. In a later change,
ExoPlayerImplInternal will create SampleSources for different playlist item
indices as necessary.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=123312595

demo/src/main/AndroidManifest.xml

@@ -66,6 +66,10 @@
         <data android:scheme="asset"/>
         <data android:scheme="file"/>
       </intent-filter>
+      <intent-filter>
+        <action android:name="com.google.android.exoplayer.demo.action.VIEW_LIST"/>
+        <category android:name="android.intent.category.DEFAULT"/>
+      </intent-filter>
     </activity>
 
   </application>

demo/src/main/java/com/google/android/exoplayer/demo/PlayerActivity.java

@@ -25,27 +25,19 @@ import com.google.android.exoplayer.ExoPlayer;
 import com.google.android.exoplayer.ExoPlayerFactory;
 import com.google.android.exoplayer.MediaCodecTrackRenderer.DecoderInitializationException;
 import com.google.android.exoplayer.MediaCodecUtil.DecoderQueryException;
-import com.google.android.exoplayer.SampleSource;
 import com.google.android.exoplayer.SimpleExoPlayer;
 import com.google.android.exoplayer.TrackGroupArray;
-import com.google.android.exoplayer.dash.DashSampleSource;
 import com.google.android.exoplayer.drm.DrmSessionManager;
 import com.google.android.exoplayer.drm.StreamingDrmSessionManager;
 import com.google.android.exoplayer.drm.UnsupportedDrmException;
-import com.google.android.exoplayer.extractor.ExtractorSampleSource;
-import com.google.android.exoplayer.hls.HlsSampleSource;
 import com.google.android.exoplayer.metadata.id3.GeobFrame;
 import com.google.android.exoplayer.metadata.id3.Id3Frame;
 import com.google.android.exoplayer.metadata.id3.PrivFrame;
 import com.google.android.exoplayer.metadata.id3.TxxxFrame;
-import com.google.android.exoplayer.smoothstreaming.SmoothStreamingSampleSource;
 import com.google.android.exoplayer.text.CaptionStyleCompat;
 import com.google.android.exoplayer.text.Cue;
 import com.google.android.exoplayer.text.SubtitleLayout;
-import com.google.android.exoplayer.upstream.Allocator;
-import com.google.android.exoplayer.upstream.DataSource;
 import com.google.android.exoplayer.upstream.DataSourceFactory;
-import com.google.android.exoplayer.upstream.DefaultAllocator;
 import com.google.android.exoplayer.upstream.DefaultDataSourceFactory;
 import com.google.android.exoplayer.util.DebugTextViewHelper;
 import com.google.android.exoplayer.util.PlayerControl;
@@ -60,7 +52,6 @@ import android.content.pm.PackageManager;
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.Handler;
-import android.text.TextUtils;
 import android.util.Log;
 import android.view.KeyEvent;
 import android.view.MotionEvent;
@@ -99,7 +90,11 @@ public class PlayerActivity extends Activity implements SurfaceHolder.Callback,
   public static final String USE_EXTENSION_DECODERS = "use_extension_decoders";
 
   // For use when launching the demo app using adb.
+  public static final String ACTION_VIEW = "com.google.android.exoplayer.demo.action.VIEW";
+  private static final String ACTION_VIEW_LIST =
+      "com.google.android.exoplayer.demo.action.VIEW_LIST";
   private static final String CONTENT_EXT_EXTRA = "type";
+  private static final String URIS_LIST_EXTRA = "uris";
 
   private static final String TAG = "PlayerActivity";
 
@@ -246,40 +241,10 @@ public class PlayerActivity extends Activity implements SurfaceHolder.Callback,
     }
   }
 
-  // Permission management methods
-
-  /**
-   * Checks whether it is necessary to ask for permission to read storage. If necessary, it also
-   * requests permission.
-   *
-   * @param uri A URI that may require {@link permission#READ_EXTERNAL_STORAGE} to play.
-   * @return True if a permission request is made. False if it is not necessary.
-   */
-  @TargetApi(23)
-  private boolean maybeRequestPermission(Uri uri) {
-    if (requiresPermission(uri)) {
-      requestPermissions(new String[] {permission.READ_EXTERNAL_STORAGE}, 0);
-      return true;
-    } else {
-      return false;
-    }
-  }
-
-  @TargetApi(23)
-  private boolean requiresPermission(Uri uri) {
-    return Util.SDK_INT >= 23
-        && Util.isLocalFileUri(uri)
-        && checkSelfPermission(permission.READ_EXTERNAL_STORAGE)
-        != PackageManager.PERMISSION_GRANTED;
-  }
-
   // Internal methods
 
   private void initializePlayer() {
     Intent intent = getIntent();
-    Uri uri = intent.getData();
-    int type = intent.getIntExtra(CONTENT_TYPE_EXTRA,
-        inferContentType(uri, intent.getStringExtra(CONTENT_EXT_EXTRA)));
     if (player == null) {
       boolean useExtensionDecoders = intent.getBooleanExtra(USE_EXTENSION_DECODERS, false);
       UUID drmSchemeUuid = (UUID) intent.getSerializableExtra(DRM_SCHEME_UUID_EXTRA);
@@ -318,11 +283,31 @@ public class PlayerActivity extends Activity implements SurfaceHolder.Callback,
       playerNeedsSource = true;
     }
     if (playerNeedsSource) {
-      if (maybeRequestPermission(uri)) {
+      String action = intent.getAction();
+      Uri[] uris;
+      UriSampleSourceProvider sourceProvider;
+      if (ACTION_VIEW.equals(action)) {
+        uris = new Uri[] {intent.getData()};
+        sourceProvider = new UriSampleSourceProvider(player, dataSourceFactory, intent.getData(),
+            intent.getIntExtra(CONTENT_TYPE_EXTRA, UriSampleSourceProvider.UNKNOWN_TYPE),
+            intent.getStringExtra(CONTENT_EXT_EXTRA), mainHandler, eventLogger);
+      } else if (ACTION_VIEW_LIST.equals(action)) {
+        String[] uriStrings = intent.getStringArrayExtra(URIS_LIST_EXTRA);
+        uris = new Uri[uriStrings.length];
+        for (int i = 0; i < uriStrings.length; i++) {
+          uris[i] = Uri.parse(uriStrings[i]);
+        }
+        sourceProvider = new UriSampleSourceProvider(player, dataSourceFactory, uris, mainHandler,
+            eventLogger);
+      } else {
+        Log.w(TAG, "Unexpected intent action: " + action);
+        return;
+      }
+      if (maybeRequestPermission(uris)) {
         // The player will be reinitialized if permission is granted.
         return;
       }
-      player.setSource(buildSource(type, uri));
+      player.setSourceProvider(sourceProvider);
       playerNeedsSource = false;
       updateButtonVisibilities();
     }
@@ -351,25 +336,28 @@ public class PlayerActivity extends Activity implements SurfaceHolder.Callback,
     Toast.makeText(getApplicationContext(), errorString, Toast.LENGTH_LONG).show();
   }
 
-  private SampleSource buildSource(int type, Uri uri) {
+  /**
-    switch (type) {
+   * Checks whether it is necessary to ask for permission to read storage. If necessary, it also
-      case Util.TYPE_SS:
+   * requests permission.
-        return new SmoothStreamingSampleSource(uri, dataSourceFactory, player.getBandwidthMeter(),
+   *
-            mainHandler, eventLogger);
+   * @param uris URIs that may require {@link permission#READ_EXTERNAL_STORAGE} to play.
-      case Util.TYPE_DASH:
+   * @return True if a permission request is made. False if it is not necessary.
-        return new DashSampleSource(uri, dataSourceFactory, player.getBandwidthMeter(), mainHandler,
+   */
-            eventLogger);
+  @TargetApi(23)
-      case Util.TYPE_HLS:
+  private boolean maybeRequestPermission(Uri... uris) {
-        return new HlsSampleSource(uri, dataSourceFactory, player.getBandwidthMeter(), mainHandler,
+    if (Util.SDK_INT >= 23) {
-            eventLogger);
+      for (Uri uri : uris) {
-      case Util.TYPE_OTHER:
+        if (Util.isLocalFileUri(uri)) {
-        Allocator allocator = new DefaultAllocator(C.DEFAULT_BUFFER_SEGMENT_SIZE);
+          if (checkSelfPermission(permission.READ_EXTERNAL_STORAGE)
-        DataSource dataSource = dataSourceFactory.createDataSource(player.getBandwidthMeter());
+              != PackageManager.PERMISSION_GRANTED) {
-        return new ExtractorSampleSource(uri, dataSource, allocator, C.DEFAULT_MUXED_BUFFER_SIZE,
+            requestPermissions(new String[] {permission.READ_EXTERNAL_STORAGE}, 0);
-            mainHandler, eventLogger, 0, ExtractorSampleSource.newDefaultExtractors());
+            return true;
-      default:
+          }
-        throw new IllegalStateException("Unsupported type: " + type);
+          break;
+        }
+      }
     }
+    return false;
   }
 
   private void releasePlayer() {
@@ -585,20 +573,6 @@ public class PlayerActivity extends Activity implements SurfaceHolder.Callback,
     return CaptionStyleCompat.createFromCaptionStyle(captioningManager.getUserStyle());
   }
 
-  /**
-   * Makes a best guess to infer the type from a media {@link Uri} and an optional overriding file
-   * extension.
-   *
-   * @param uri The {@link Uri} of the media.
-   * @param fileExtension An overriding file extension.
-   * @return The inferred type.
-   */
-  private static int inferContentType(Uri uri, String fileExtension) {
-    String lastPathSegment = !TextUtils.isEmpty(fileExtension) ? "." + fileExtension
-        : uri.getLastPathSegment();
-    return Util.inferContentType(lastPathSegment);
-  }
-
   private static final class KeyCompatibleMediaController extends MediaController {
 
     private MediaController.MediaPlayerControl playerControl;

demo/src/main/java/com/google/android/exoplayer/demo/SampleChooserActivity.java

@@ -91,6 +91,7 @@ public class SampleChooserActivity extends Activity {
 
   private void onSampleSelected(Sample sample) {
     Intent intent = new Intent(this, PlayerActivity.class)
+        .setAction(PlayerActivity.ACTION_VIEW)
         .setData(Uri.parse(sample.uri))
         .putExtra(PlayerActivity.CONTENT_TYPE_EXTRA, sample.type)
         .putExtra(PlayerActivity.DRM_SCHEME_UUID_EXTRA, sample.drmSchemeUuid)

demo/src/main/java/com/google/android/exoplayer/demo/UriSampleSourceProvider.java

@@ -0,0 +1,142 @@
+/*
+ * Copyright (C) 2014 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.exoplayer.demo;
+
+import com.google.android.exoplayer.C;
+import com.google.android.exoplayer.SampleSource;
+import com.google.android.exoplayer.SampleSourceProvider;
+import com.google.android.exoplayer.SimpleExoPlayer;
+import com.google.android.exoplayer.dash.DashSampleSource;
+import com.google.android.exoplayer.extractor.ExtractorSampleSource;
+import com.google.android.exoplayer.hls.HlsSampleSource;
+import com.google.android.exoplayer.smoothstreaming.SmoothStreamingSampleSource;
+import com.google.android.exoplayer.upstream.Allocator;
+import com.google.android.exoplayer.upstream.DataSource;
+import com.google.android.exoplayer.upstream.DataSourceFactory;
+import com.google.android.exoplayer.upstream.DefaultAllocator;
+import com.google.android.exoplayer.util.Util;
+
+import android.net.Uri;
+import android.os.Handler;
+import android.text.TextUtils;
+
+/**
+ * Provides {@link SampleSource}s to play back media loaded from one or more URI/URIs.
+ */
+public final class UriSampleSourceProvider implements SampleSourceProvider {
+
+  public static final int UNKNOWN_TYPE = -1;
+
+  private final SimpleExoPlayer player;
+  private final DataSourceFactory dataSourceFactory;
+  private final Uri[] uris;
+  private final String overrideExtension;
+  private final int type;
+  private final Handler handler;
+  private final EventLogger eventLogger;
+
+  /**
+   * Constructs a source provider for {@link SampleSource} to play back media at the specified
+   * URI, using the specified type.
+   *
+   * @param player The demo player, which will listen to source events.
+   * @param dataSourceFactory A data source factory.
+   * @param uri The URI to play back.
+   * @param type A {@code PlayerActivity.TYPE_*} constant specifying the type of the source, or
+   *     {@link #UNKNOWN_TYPE}, in which case it is inferred from the URI's extension.
+   * @param overrideExtension An overriding file extension used when inferring the source's type,
+   *     or {@code null}.
+   * @param handler A handler to use for logging events.
+   * @param eventLogger An event logger.
+   */
+  public UriSampleSourceProvider(SimpleExoPlayer player, DataSourceFactory dataSourceFactory,
+      Uri uri, int type, String overrideExtension, Handler handler, EventLogger eventLogger) {
+    this.player = player;
+    this.dataSourceFactory = dataSourceFactory;
+    this.overrideExtension = overrideExtension;
+    this.type = type;
+    this.handler = handler;
+    this.eventLogger = eventLogger;
+
+    uris = new Uri[] {uri};
+  }
+
+  /**
+   * Constructs a source provider for {@link SampleSource}s to play back media at one or more
+   * {@link Uri}s. The content type of each URI is inferred based on its last path segment.
+   *
+   * @param player The demo player, which will listen to source events.
+   * @param dataSourceFactory A data source factory.
+   * @param uris The URIs to play back.
+   * @param handler A handler to use for logging events.
+   * @param eventLogger An event logger.
+   */
+  public UriSampleSourceProvider(SimpleExoPlayer player, DataSourceFactory dataSourceFactory,
+      Uri[] uris, Handler handler, EventLogger eventLogger) {
+    this.player = player;
+    this.dataSourceFactory = dataSourceFactory;
+    this.uris = uris;
+    this.handler = handler;
+    this.eventLogger = eventLogger;
+
+    overrideExtension = null;
+    type = UNKNOWN_TYPE;
+  }
+
+  @Override
+  public int getSourceCount() {
+    return uris.length;
+  }
+
+  @Override
+  public SampleSource createSource(int index) {
+    Uri uri = uris[index];
+    int type = this.type == UNKNOWN_TYPE ? inferContentType(uri, overrideExtension) : this.type;
+    switch (type) {
+      case Util.TYPE_SS:
+        return new SmoothStreamingSampleSource(uri, dataSourceFactory, player.getBandwidthMeter(),
+            handler, eventLogger);
+      case Util.TYPE_DASH:
+        return new DashSampleSource(uri, dataSourceFactory, player.getBandwidthMeter(), handler,
+            eventLogger);
+      case Util.TYPE_HLS:
+        return new HlsSampleSource(uri, dataSourceFactory, player.getBandwidthMeter(), handler,
+            eventLogger);
+      case Util.TYPE_OTHER:
+        Allocator allocator = new DefaultAllocator(C.DEFAULT_BUFFER_SEGMENT_SIZE);
+        DataSource dataSource = dataSourceFactory.createDataSource(player.getBandwidthMeter());
+        return new ExtractorSampleSource(uri, dataSource, allocator, C.DEFAULT_MUXED_BUFFER_SIZE,
+            handler, eventLogger, 0, ExtractorSampleSource.newDefaultExtractors());
+      default:
+        throw new IllegalStateException("Unsupported type: " + type);
+    }
+  }
+
+  /**
+   * Makes a best guess to infer the type from a media {@link Uri} and an optional overriding file
+   * extension.
+   *
+   * @param uri The {@link Uri} of the media.
+   * @param fileExtension An overriding file extension.
+   * @return The inferred type.
+   */
+  private static int inferContentType(Uri uri, String fileExtension) {
+    String lastPathSegment = !TextUtils.isEmpty(fileExtension) ? "." + fileExtension
+        : uri.getLastPathSegment();
+    return Util.inferContentType(lastPathSegment);
+  }
+
+}

library/src/main/java/com/google/android/exoplayer/ExoPlayer.java

@@ -84,7 +84,8 @@ package com.google.android.exoplayer;
  *
  * <p>The possible playback state transitions are shown below. Transitions can be triggered either
  * by changes in the state of the {@link TrackRenderer}s being used, or as a result of
- * {@link #setSource(SampleSource)}, {@link #stop()} or {@link #release()} being invoked.</p>
+ * {@link #setSource(SampleSource)}, {@link #setSourceProvider(SampleSourceProvider)},
+ * {@link #stop()} or {@link #release()} being invoked.</p>
  * <p align="center"><img src="../../../../../images/exoplayer_playbackstate.png"
  *     alt="ExoPlayer playback state transitions"
  *     border="0"/></p>
@@ -225,6 +226,14 @@ public interface ExoPlayer {
    */
   void setSource(SampleSource sampleSource);
 
+  /**
+   * Sets the player's source provider. The player will transition to {@link #STATE_BUFFERING} until
+   * it is ready to play the first source.
+   *
+   * @param sourceProvider The provider of {@link SampleSource}s to play.
+   */
+  void setSourceProvider(SampleSourceProvider sourceProvider);
+
   /**
    * Sets whether playback should proceed when {@link #getPlaybackState()} == {@link #STATE_READY}.
    * If the player is already in this state, then this method can be used to pause and resume

library/src/main/java/com/google/android/exoplayer/ExoPlayerImpl.java

@@ -86,8 +86,13 @@ import java.util.concurrent.CopyOnWriteArraySet;
   }
 
   @Override
-  public void setSource(SampleSource source) {
+  public void setSource(final SampleSource sampleSource) {
-    internalPlayer.setSource(source);
+    internalPlayer.setSourceProvider(new SingleSampleSourceProvider(sampleSource));
+  }
+
+  @Override
+  public void setSourceProvider(SampleSourceProvider sourceProvider) {
+    internalPlayer.setSourceProvider(sourceProvider);
   }
 
   @Override
@@ -190,4 +195,25 @@ import java.util.concurrent.CopyOnWriteArraySet;
     }
   }
 
+  private static final class SingleSampleSourceProvider implements SampleSourceProvider {
+
+    private final SampleSource sampleSource;
+
+    public SingleSampleSourceProvider(SampleSource sampleSource) {
+      this.sampleSource = sampleSource;
+    }
+
+    @Override
+    public int getSourceCount() {
+      return 1;
+    }
+
+    @Override
+    public SampleSource createSource(int index) {
+      // The source will only be created once.
+      return sampleSource;
+    }
+
+  }
+
 }

library/src/main/java/com/google/android/exoplayer/ExoPlayerImplInternal.java

@@ -48,7 +48,7 @@ import java.util.concurrent.atomic.AtomicInteger;
   public static final int MSG_ERROR = 3;
 
   // Internal messages
-  private static final int MSG_SET_SOURCE = 0;
+  private static final int MSG_SET_SOURCE_PROVIDER = 0;
   private static final int MSG_SET_PLAY_WHEN_READY = 1;
   private static final int MSG_DO_SOME_WORK = 2;
   private static final int MSG_SEEK_TO = 3;
@@ -135,8 +135,8 @@ import java.util.concurrent.atomic.AtomicInteger;
     return durationUs == C.UNSET_TIME_US ? ExoPlayer.UNKNOWN_TIME : durationUs / 1000;
   }
 
-  public void setSource(SampleSource sampleSource) {
+  public void setSourceProvider(SampleSourceProvider sourceProvider) {
-    handler.obtainMessage(MSG_SET_SOURCE, sampleSource).sendToTarget();
+    handler.obtainMessage(MSG_SET_SOURCE_PROVIDER, sourceProvider).sendToTarget();
   }
 
   public void setPlayWhenReady(boolean playWhenReady) {
@@ -203,8 +203,8 @@ import java.util.concurrent.atomic.AtomicInteger;
   public boolean handleMessage(Message msg) {
     try {
       switch (msg.what) {
-        case MSG_SET_SOURCE: {
+        case MSG_SET_SOURCE_PROVIDER: {
-          setSourceInternal((SampleSource) msg.obj);
+          setSourceProviderInternal((SampleSourceProvider) msg.obj);
           return true;
         }
         case MSG_SET_PLAY_WHEN_READY: {
@@ -277,9 +277,10 @@ import java.util.concurrent.atomic.AtomicInteger;
         || (durationUs != C.UNSET_TIME_US && bufferedPositionUs >= durationUs);
   }
 
-  private void setSourceInternal(SampleSource source) {
+  private void setSourceProviderInternal(SampleSourceProvider sourceProvider) {
     resetInternal();
-    this.source = source;
+    // TODO[playlists]: Create and use sources after the first one.
+    this.source = sourceProvider.createSource(0);
     setState(ExoPlayer.STATE_BUFFERING);
     handler.sendEmptyMessage(MSG_DO_SOME_WORK);
   }

library/src/main/java/com/google/android/exoplayer/SampleSourceProvider.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2014 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.exoplayer;
+
+// TODO[playlists]: Rename this and maybe change the interface once we support multi-period DASH.
+/**
+ * Provides a sequence of {@link SampleSource}s to play back.
+ */
+public interface SampleSourceProvider {
+
+  /**
+   * Returned by {@link #getSourceCount()} if the number of sources is not known.
+   */
+  int UNKNOWN_SOURCE_COUNT = -1;
+
+  /**
+   * Returns the number of sources in the sequence, or {@link #UNKNOWN_SOURCE_COUNT} if the number
+   * of sources is not yet known.
+   */
+  int getSourceCount();
+
+  /**
+   * Returns a new {@link SampleSource} providing media at the specified index in the sequence, or
+   * {@code null} if the source at the specified index is not yet available.
+   *
+   * @param index The index of the source to create, which must be less than the count returned by
+   *     {@link #getSourceCount()}.
+   * @return A new {@link SampleSource}, or {@code null} if the source at the specified index is not
+   *     yet available.
+   */
+  SampleSource createSource(int index);
+
+}

library/src/main/java/com/google/android/exoplayer/SimpleExoPlayer.java

@@ -287,8 +287,13 @@ public final class SimpleExoPlayer implements ExoPlayer {
   }
 
   @Override
-  public void setSource(SampleSource source) {
+  public void setSource(SampleSource sampleSource) {
-    player.setSource(source);
+    player.setSource(sampleSource);
+  }
+
+  @Override
+  public void setSourceProvider(SampleSourceProvider sourceProvider) {
+    player.setSourceProvider(sourceProvider);
   }
 
   @Override