Allow playing ads in playlists

- Remove restriction on `AdsMediaSource`s in playlists in `ExoPlayerImpl`.
- Allow playing playlists of `AdsMediaSource`s in the demo app.
- Add a sample with ads in a playlist in the demo app.

Issue: #3750
PiperOrigin-RevId: 344018774

RELEASENOTES.md

@@ -69,6 +69,8 @@
         existing decoder instance for the new format, and if not then the
         reasons why.
 *   IMA extension:
+    *   Add support for playback of ads in playlists
+        ([#3750](https://github.com/google/ExoPlayer/issues/3750)).
     *   Upgrade IMA SDK dependency to 3.21.0, and release the `AdsLoader`
         ([#7344](https://github.com/google/ExoPlayer/issues/7344)).
     *   Improve handling of ad tags with unsupported VPAID ads
@@ -76,6 +78,7 @@
     *   Fix a bug that caused multiple ads in an ad pod to be skipped when one
         ad in the ad pod was skipped.
     *   Fix passing an ads response to the `ImaAdsLoader` builder.
+    *   Set the overlay language based on the device locale by default.
 *   Cronet extension:
     *   Fix handling of HTTP status code 200 when making unbounded length range
         requests ([#8090](https://github.com/google/ExoPlayer/issues/8090)).
@@ -88,8 +91,6 @@
     *   Notify onBufferingEnded when the state of origin player becomes
         STATE_IDLE or STATE_ENDED.
     *   Allow to remove all playlist items that makes the player reset.
-*   IMA extension:
-    *   Set the overlay language based on the device locale by default.
 
 ### 2.12.1 (2020-10-23) ###
 

demos/main/src/main/assets/media.exolist.json

@@ -502,6 +502,23 @@
         "name": "VMAP midroll ad pod at 5 s with 10 skippable ads",
         "uri": "https://storage.googleapis.com/exoplayer-test-media-1/mp4/frame-counter-one-hour.mp4",
         "ad_tag_uri": "https://vastsynthesizer.appspot.com/midroll-10-skippable-ads"
+      },
+      {
+        "name": "Playlist with three ad tags",
+        "playlist": [
+          {
+            "uri": "https://storage.googleapis.com/exoplayer-test-media-1/mp4/android-screens-10s.mp4",
+            "ad_tag_uri": "https://pubads.g.doubleclick.net/gampad/ads?sz=640x480&iu=/124319096/external/single_ad_samples&ciu_szs=300x250&impl=s&gdfp_req=1&env=vp&output=vast&unviewed_position_start=1&cust_params=deployment%3Ddevsite%26sample_ct%3Dlinear&correlator="
+          },
+          {
+            "uri": "https://storage.googleapis.com/exoplayer-test-media-1/mp4/android-screens-25s.mp4",
+            "ad_tag_uri": "https://pubads.g.doubleclick.net/gampad/ads?sz=640x480&iu=/124319096/external/ad_rule_samples&ciu_szs=300x250&ad_rule=1&impl=s&gdfp_req=1&env=vp&output=vmap&unviewed_position_start=1&cust_params=deployment%3Ddevsite%26sample_ar%3Dpremidpost&cmsid=496&vid=short_onecue&correlator="
+          },
+          {
+            "uri": "https://storage.googleapis.com/exoplayer-test-media-1/mp4/frame-counter-one-hour.mp4",
+            "ad_tag_uri": "https://pubads.g.doubleclick.net/gampad/ads?sz=640x480&iu=/124319096/external/ad_rule_samples&ciu_szs=300x250&ad_rule=1&impl=s&gdfp_req=1&env=vp&output=vmap&unviewed_position_start=1&cust_params=deployment%3Ddevsite%26sample_ar%3Dpremidpostlongpod&cmsid=496&vid=short_tencue&correlator="
+          }
+        ]
       }
     ]
   },

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

@@ -355,11 +355,6 @@ public class PlayerActivity extends AppCompatActivity
   }
 
   private AdsLoader getAdsLoader(MediaItem.AdsConfiguration adsConfiguration) {
-    if (mediaItems.size() > 1) {
-      showToast(R.string.unsupported_ads_in_playlist);
-      releaseAdsLoader();
-      return null;
-    }
     // The ads loader is reused for multiple playbacks, so that ad playback can resume.
     if (adsLoader == null) {
       adsLoader = new ImaAdsLoader.Builder(/* context= */ this).build();

demos/main/src/main/res/values/strings.xml

@@ -45,8 +45,6 @@
 
   <string name="sample_list_load_error">One or more sample lists failed to load</string>
 
-  <string name="unsupported_ads_in_playlist">Playing without ads, as ads are not supported in playlists</string>
-
   <string name="download_start_error">Failed to start download</string>
 
   <string name="download_start_error_offline_license">Failed to obtain offline license</string>

library/core/src/main/java/com/google/android/exoplayer2/ExoPlayerImpl.java

@@ -34,7 +34,6 @@ import com.google.android.exoplayer2.source.MediaSource.MediaPeriodId;
 import com.google.android.exoplayer2.source.MediaSourceFactory;
 import com.google.android.exoplayer2.source.ShuffleOrder;
 import com.google.android.exoplayer2.source.TrackGroupArray;
-import com.google.android.exoplayer2.source.ads.AdsMediaSource;
 import com.google.android.exoplayer2.trackselection.TrackSelection;
 import com.google.android.exoplayer2.trackselection.TrackSelectionArray;
 import com.google.android.exoplayer2.trackselection.TrackSelector;
@@ -92,7 +91,6 @@ import java.util.concurrent.TimeoutException;
   private SeekParameters seekParameters;
   private ShuffleOrder shuffleOrder;
   private boolean pauseAtEndOfMediaItems;
-  private boolean hasAdsMediaSource;
 
   // Playback information when there is no pending seek/set source operation.
   private PlaybackInfo playbackInfo;
@@ -435,7 +433,6 @@ import java.util.concurrent.TimeoutException;
   @Override
   public void addMediaSources(int index, List<MediaSource> mediaSources) {
     Assertions.checkArgument(index >= 0);
-    validateMediaSources(mediaSources, /* mediaSourceReplacement= */ false);
     Timeline oldTimeline = getCurrentTimeline();
     pendingOperationAcks++;
     List<MediaSourceList.MediaSourceHolder> holders = addMediaSourceHolders(index, mediaSources);
@@ -1140,7 +1137,6 @@ import java.util.concurrent.TimeoutException;
       int startWindowIndex,
       long startPositionMs,
       boolean resetToDefaultPosition) {
-    validateMediaSources(mediaSources, /* mediaSourceReplacement= */ true);
     int currentWindowIndex = getCurrentWindowIndexInternal();
     long currentPositionMs = getCurrentPosition();
     pendingOperationAcks++;
@@ -1239,39 +1235,6 @@ import java.util.concurrent.TimeoutException;
       mediaSourceHolderSnapshots.remove(i);
     }
     shuffleOrder = shuffleOrder.cloneAndRemove(fromIndex, toIndexExclusive);
-    if (mediaSourceHolderSnapshots.isEmpty()) {
-      hasAdsMediaSource = false;
-    }
-  }
-
-  /**
-   * Validates media sources before any modification of the existing list of media sources is made.
-   * This way we can throw an exception before changing the state of the player in case of a
-   * validation failure.
-   *
-   * @param mediaSources The media sources to set or add.
-   * @param mediaSourceReplacement Whether the given media sources will replace existing ones.
-   */
-  private void validateMediaSources(
-      List<MediaSource> mediaSources, boolean mediaSourceReplacement) {
-    if (hasAdsMediaSource && !mediaSourceReplacement && !mediaSources.isEmpty()) {
-      // Adding media sources to an ads media source is not allowed
-      // (see https://github.com/google/ExoPlayer/issues/3750).
-      throw new IllegalStateException();
-    }
-    int sizeAfterModification =
-        mediaSources.size() + (mediaSourceReplacement ? 0 : mediaSourceHolderSnapshots.size());
-    for (int i = 0; i < mediaSources.size(); i++) {
-      MediaSource mediaSource = checkNotNull(mediaSources.get(i));
-      if (mediaSource instanceof AdsMediaSource) {
-        if (sizeAfterModification > 1) {
-          // Ads media sources only allowed with a single source
-          // (see https://github.com/google/ExoPlayer/issues/3750).
-          throw new IllegalArgumentException();
-        }
-        hasAdsMediaSource = true;
-      }
-    }
   }
 
   private Timeline createMaskingTimeline() {

library/core/src/test/java/com/google/android/exoplayer2/ExoPlayerTest.java

@@ -47,7 +47,6 @@ import android.media.AudioManager;
 import android.net.Uri;
 import android.os.Looper;
 import android.view.Surface;
-import android.view.ViewGroup;
 import androidx.annotation.Nullable;
 import androidx.test.core.app.ApplicationProvider;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
@@ -65,7 +64,6 @@ import com.google.android.exoplayer2.robolectric.TestPlayerRunHelper;
 import com.google.android.exoplayer2.source.ClippingMediaSource;
 import com.google.android.exoplayer2.source.CompositeMediaSource;
 import com.google.android.exoplayer2.source.ConcatenatingMediaSource;
-import com.google.android.exoplayer2.source.DefaultMediaSourceFactory;
 import com.google.android.exoplayer2.source.LoopingMediaSource;
 import com.google.android.exoplayer2.source.MaskingMediaSource;
 import com.google.android.exoplayer2.source.MediaPeriod;
@@ -77,8 +75,6 @@ import com.google.android.exoplayer2.source.SilenceMediaSource;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
 import com.google.android.exoplayer2.source.ads.AdPlaybackState;
-import com.google.android.exoplayer2.source.ads.AdsLoader;
-import com.google.android.exoplayer2.source.ads.AdsMediaSource;
 import com.google.android.exoplayer2.testutil.Action;
 import com.google.android.exoplayer2.testutil.ActionSchedule;
 import com.google.android.exoplayer2.testutil.ActionSchedule.PlayerRunnable;
@@ -106,7 +102,6 @@ import com.google.android.exoplayer2.trackselection.TrackSelection;
 import com.google.android.exoplayer2.trackselection.TrackSelectionArray;
 import com.google.android.exoplayer2.upstream.Allocation;
 import com.google.android.exoplayer2.upstream.Allocator;
-import com.google.android.exoplayer2.upstream.DataSpec;
 import com.google.android.exoplayer2.upstream.Loader;
 import com.google.android.exoplayer2.upstream.TransferListener;
 import com.google.android.exoplayer2.util.Assertions;
@@ -5571,124 +5566,6 @@ public final class ExoPlayerTest {
     assertThat(positionAfterSetShuffleOrder.get()).isAtLeast(5000);
   }
 
-  @Test
-  public void setMediaSources_secondAdMediaSource_throws() throws Exception {
-    AdsMediaSource adsMediaSource =
-        new AdsMediaSource(
-            new FakeMediaSource(new FakeTimeline(/* windowCount= */ 1)),
-            /* adTagDataSpec= */ new DataSpec(Uri.EMPTY),
-            /* adsId= */ new Object(),
-            new DefaultMediaSourceFactory(context),
-            new FakeAdsLoader(),
-            new FakeAdViewProvider());
-    Exception[] exception = {null};
-    ActionSchedule actionSchedule =
-        new ActionSchedule.Builder(TAG)
-            .executeRunnable(
-                new PlayerRunnable() {
-                  @Override
-                  public void run(SimpleExoPlayer player) {
-                    try {
-                      player.setMediaSource(adsMediaSource);
-                      player.addMediaSource(adsMediaSource);
-                    } catch (Exception e) {
-                      exception[0] = e;
-                    }
-                    player.prepare();
-                  }
-                })
-            .build();
-
-    new ExoPlayerTestRunner.Builder(context)
-        .setActionSchedule(actionSchedule)
-        .build()
-        .start(/* doPrepare= */ false)
-        .blockUntilActionScheduleFinished(TIMEOUT_MS)
-        .blockUntilEnded(TIMEOUT_MS);
-
-    assertThat(exception[0]).isInstanceOf(IllegalStateException.class);
-  }
-
-  @Test
-  public void setMediaSources_multipleMediaSourcesWithAd_throws() throws Exception {
-    MediaSource mediaSource = new FakeMediaSource(new FakeTimeline(/* windowCount= */ 1));
-    AdsMediaSource adsMediaSource =
-        new AdsMediaSource(
-            mediaSource,
-            /* adTagDataSpec= */ new DataSpec(Uri.EMPTY),
-            /* adsId= */ new Object(),
-            new DefaultMediaSourceFactory(context),
-            new FakeAdsLoader(),
-            new FakeAdViewProvider());
-    final Exception[] exception = {null};
-    ActionSchedule actionSchedule =
-        new ActionSchedule.Builder(TAG)
-            .executeRunnable(
-                new PlayerRunnable() {
-                  @Override
-                  public void run(SimpleExoPlayer player) {
-                    try {
-                      List<MediaSource> sources = new ArrayList<>();
-                      sources.add(mediaSource);
-                      sources.add(adsMediaSource);
-                      player.setMediaSources(sources);
-                    } catch (Exception e) {
-                      exception[0] = e;
-                    }
-                    player.prepare();
-                  }
-                })
-            .build();
-
-    new ExoPlayerTestRunner.Builder(context)
-        .setActionSchedule(actionSchedule)
-        .build()
-        .start(/* doPrepare= */ false)
-        .blockUntilActionScheduleFinished(TIMEOUT_MS)
-        .blockUntilEnded(TIMEOUT_MS);
-
-    assertThat(exception[0]).isInstanceOf(IllegalArgumentException.class);
-  }
-
-  @Test
-  public void setMediaSources_addingMediaSourcesWithAdToNonEmptyPlaylist_throws() throws Exception {
-    MediaSource mediaSource = new FakeMediaSource(new FakeTimeline(/* windowCount= */ 1));
-    AdsMediaSource adsMediaSource =
-        new AdsMediaSource(
-            mediaSource,
-            /* adTagDataSpec= */ new DataSpec(Uri.EMPTY),
-            /* adsId= */ new Object(),
-            new DefaultMediaSourceFactory(context),
-            new FakeAdsLoader(),
-            new FakeAdViewProvider());
-    final Exception[] exception = {null};
-    ActionSchedule actionSchedule =
-        new ActionSchedule.Builder(TAG)
-            .waitForPlaybackState(Player.STATE_READY)
-            .executeRunnable(
-                new PlayerRunnable() {
-                  @Override
-                  public void run(SimpleExoPlayer player) {
-                    try {
-                      player.addMediaSource(adsMediaSource);
-                    } catch (Exception e) {
-                      exception[0] = e;
-                    }
-                  }
-                })
-            .build();
-
-    new ExoPlayerTestRunner.Builder(context)
-        .setMediaSources(mediaSource)
-        .setActionSchedule(actionSchedule)
-        .build()
-        .start()
-        .blockUntilActionScheduleFinished(TIMEOUT_MS)
-        .blockUntilEnded(TIMEOUT_MS);
-
-    assertThat(exception[0]).isInstanceOf(IllegalArgumentException.class);
-  }
-
   @Test
   public void setMediaSources_empty_whenEmpty_correctMaskingWindowIndex() throws Exception {
     Timeline secondTimeline = new FakeTimeline(/* windowCount= */ 1);
@@ -9117,53 +8994,6 @@ public final class ExoPlayerTest {
     }
   }
 
-  private static class FakeAdsLoader implements AdsLoader {
-
-    @Override
-    public void setPlayer(@Nullable Player player) {}
-
-    @Override
-    public void release() {}
-
-    @Override
-    public void setSupportedContentTypes(int... contentTypes) {}
-
-    @Override
-    public void start(
-        AdsMediaSource adsMediaSource,
-        DataSpec adTagDataSpec,
-        Object adsId,
-        AdViewProvider adViewProvider,
-        AdsLoader.EventListener eventListener) {}
-
-    @Override
-    public void stop(AdsMediaSource adsMediaSource) {}
-
-    @Override
-    public void handlePrepareComplete(
-        AdsMediaSource adsMediaSource, int adGroupIndex, int adIndexInAdGroup) {}
-
-    @Override
-    public void handlePrepareError(
-        AdsMediaSource adsMediaSource,
-        int adGroupIndex,
-        int adIndexInAdGroup,
-        IOException exception) {}
-  }
-
-  private static class FakeAdViewProvider implements AdsLoader.AdViewProvider {
-
-    @Override
-    public ViewGroup getAdViewGroup() {
-      return null;
-    }
-
-    @Override
-    public ImmutableList<AdsLoader.OverlayInfo> getAdOverlayInfos() {
-      return ImmutableList.of();
-    }
-  }
-
   /**
    * Returns an argument matcher for {@link Timeline} instances that ignores period and window uids.
    */