Complete preloading when the period has loaded to the end of the source

When the period has loaded to the end of the source, the `period.getBufferedPositionUs` will be set to `C.TIME_END_OF_SOURCE`, which is a negative value. Thus, the original `continueLoadingPredicate` will never turn to `false`, as the `bufferedPositionUs` is definitely less than the target preload position that is expected to be positive.

In this change, we added `PreloadMediaSource.PreloadControl.onLoadedToTheEndOfSource(PreloadMediaSource)` to indicate that the source has loaded to the end. This allows the `DefaultPreloadManager` and the custom `PreloadMediaSource.PreloadControl` implementations to preload the next source or take other actions.

This bug was not revealed by the the `DefaultPreloadManagerTest` because the related tests were all using the `FakeMediaSource` and only setting the preload target to `STAGE_TIMELINE_REFRESHED`. Thus, the tests for testing the `invalidate()` behaviors were modified to use the real progressive media whenever possible, unless we have to use `FakeMediaSource` to squeeze a chance to do more operations between the preloading of sources to test some special scenarios.

PiperOrigin-RevId: 631776442

RELEASENOTES.md

@@ -18,6 +18,12 @@
     *   Fix issue with updating the last rebuffer time which resulted in
         incorrect `bs` (buffer starvation) key in CMCD
         ([#1124](https://github.com/androidx/media/issues/1124)).
+    *   Add
+        `PreloadMediaSource.PreloadControl.onLoadedToTheEndOfSource(PreloadMediaSource)`
+        to indicate that the source has loaded to the end. This allows the
+        `DefaultPreloadManager` and the custom
+        `PreloadMediaSource.PreloadControl` implementations to preload the next
+        source or take other actions.
 *   Transformer:
     *   Work around a decoder bug where the number of audio channels was capped
         at stereo when handling PCM input.

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/preload/DefaultPreloadManager.java

@@ -203,13 +203,17 @@ public final class DefaultPreloadManager extends BasePreloadManager<Integer> {
     @Override
     public boolean onTimelineRefreshed(PreloadMediaSource mediaSource) {
       return continueOrCompletePreloading(
-          mediaSource, status -> status.getStage() > Status.STAGE_TIMELINE_REFRESHED);
+          mediaSource,
+          /* continueLoadingPredicate= */ status ->
+              status.getStage() > Status.STAGE_TIMELINE_REFRESHED);
     }
 
     @Override
     public boolean onPrepared(PreloadMediaSource mediaSource) {
       return continueOrCompletePreloading(
-          mediaSource, status -> status.getStage() > Status.STAGE_SOURCE_PREPARED);
+          mediaSource,
+          /* continueLoadingPredicate= */ status ->
+              status.getStage() > Status.STAGE_SOURCE_PREPARED);
     }
 
     @Override
@@ -217,9 +221,9 @@ public final class DefaultPreloadManager extends BasePreloadManager<Integer> {
         PreloadMediaSource mediaSource, long bufferedPositionUs) {
       return continueOrCompletePreloading(
           mediaSource,
-          status ->
+          /* continueLoadingPredicate= */ status ->
-              (status.getStage() == Status.STAGE_LOADED_TO_POSITION_MS
+              status.getStage() == Status.STAGE_LOADED_TO_POSITION_MS
-                  && status.getValue() > Util.usToMs(bufferedPositionUs)));
+                  && status.getValue() > Util.usToMs(bufferedPositionUs));
     }
 
     @Override
@@ -227,6 +231,11 @@ public final class DefaultPreloadManager extends BasePreloadManager<Integer> {
       onPreloadCompleted(mediaSource);
     }
 
+    @Override
+    public void onLoadedToTheEndOfSource(PreloadMediaSource mediaSource) {
+      onPreloadCompleted(mediaSource);
+    }
+
     private boolean continueOrCompletePreloading(
         MediaSource mediaSource, Predicate<Status> continueLoadingPredicate) {
       @Nullable

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/preload/PreloadMediaSource.java

@@ -81,9 +81,12 @@ public final class PreloadMediaSource extends WrappingMediaSource {
     /**
      * Called from {@link PreloadMediaSource} when it requests to continue loading.
      *
+     * <p>If fully loaded, then {@link #onLoadedToTheEndOfSource(PreloadMediaSource)} will be called
+     * instead.
+     *
      * @param mediaSource The {@link PreloadMediaSource} that requests to continue loading.
      * @param bufferedPositionUs An estimate of the absolute position in microseconds up to which
-     *     data is buffered, or {@link C#TIME_END_OF_SOURCE} if the track is fully buffered.
+     *     data is buffered.
      */
     boolean onContinueLoadingRequested(PreloadMediaSource mediaSource, long bufferedPositionUs);
 
@@ -93,6 +96,15 @@ public final class PreloadMediaSource extends WrappingMediaSource {
      * @param mediaSource The {@link PreloadMediaSource} that the player starts using.
      */
     void onUsedByPlayer(PreloadMediaSource mediaSource);
+
+    /**
+     * Called from {@link PreloadMediaSource} when it has loaded to the end of source.
+     *
+     * <p>The default implementation is a no-op.
+     *
+     * @param mediaSource The {@link PreloadMediaSource} that has loaded to the end of source.
+     */
+    default void onLoadedToTheEndOfSource(PreloadMediaSource mediaSource) {}
   }
 
   /** Factory for {@link PreloadMediaSource}. */
@@ -402,7 +414,9 @@ public final class PreloadMediaSource extends WrappingMediaSource {
         return;
       }
       PreloadMediaPeriod preloadMediaPeriod = (PreloadMediaPeriod) mediaPeriod;
-      if (!prepared
+      if (prepared && mediaPeriod.getBufferedPositionUs() == C.TIME_END_OF_SOURCE) {
+        preloadControl.onLoadedToTheEndOfSource(PreloadMediaSource.this);
+      } else if (!prepared
           || preloadControl.onContinueLoadingRequested(
               PreloadMediaSource.this, preloadMediaPeriod.getBufferedPositionUs())) {
         preloadMediaPeriod.continueLoading(

libraries/exoplayer/src/test/java/androidx/media3/exoplayer/source/preload/DefaultPreloadManagerTest.java

@@ -15,19 +15,25 @@
  */
 package androidx.media3.exoplayer.source.preload;
 
+import static androidx.media3.exoplayer.source.preload.DefaultPreloadManager.Status.STAGE_LOADED_TO_POSITION_MS;
+import static androidx.media3.exoplayer.source.preload.DefaultPreloadManager.Status.STAGE_TIMELINE_REFRESHED;
+import static androidx.media3.test.utils.robolectric.RobolectricUtil.runMainLooperUntil;
 import static com.google.common.truth.Truth.assertThat;
+import static java.lang.Math.abs;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 import static org.robolectric.Shadows.shadowOf;
 
 import android.content.Context;
+import android.net.Uri;
 import android.os.Looper;
 import androidx.annotation.Nullable;
 import androidx.media3.common.C;
 import androidx.media3.common.MediaItem;
 import androidx.media3.common.util.SystemClock;
 import androidx.media3.common.util.Util;
+import androidx.media3.datasource.DefaultDataSource;
 import androidx.media3.exoplayer.DefaultRendererCapabilitiesList;
 import androidx.media3.exoplayer.Renderer;
 import androidx.media3.exoplayer.RendererCapabilitiesList;
@@ -35,6 +41,7 @@ import androidx.media3.exoplayer.RenderersFactory;
 import androidx.media3.exoplayer.analytics.PlayerId;
 import androidx.media3.exoplayer.source.DefaultMediaSourceFactory;
 import androidx.media3.exoplayer.source.MediaSource;
+import androidx.media3.exoplayer.source.ProgressiveMediaSource;
 import androidx.media3.exoplayer.trackselection.DefaultTrackSelector;
 import androidx.media3.exoplayer.trackselection.TrackSelector;
 import androidx.media3.exoplayer.upstream.Allocator;
@@ -50,6 +57,7 @@ import androidx.test.core.app.ApplicationProvider;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -161,20 +169,26 @@ public class DefaultPreloadManagerTest {
   }
 
   @Test
-  public void
+  public void invalidate_withoutSettingCurrentPlayingIndex_sourcesPreloadedToTargetStatusesInOrder()
-      invalidate_withoutSettingCurrentPlayingIndex_sourcesPreloadedToTargetStatusesInOrder() {
+      throws Exception {
     ArrayList<Integer> targetPreloadStatusControlCallStates = new ArrayList<>();
+    AtomicInteger currentPlayingItemIndex = new AtomicInteger();
     TargetPreloadStatusControl<Integer> targetPreloadStatusControl =
         rankingData -> {
           targetPreloadStatusControlCallStates.add(rankingData);
-          return new DefaultPreloadManager.Status(
+          if (abs(rankingData - currentPlayingItemIndex.get()) == 1) {
-              DefaultPreloadManager.Status.STAGE_TIMELINE_REFRESHED);
+            return new DefaultPreloadManager.Status(STAGE_LOADED_TO_POSITION_MS, 100L);
+          } else {
+            return new DefaultPreloadManager.Status(STAGE_TIMELINE_REFRESHED);
+          }
         };
-    FakeMediaSourceFactory fakeMediaSourceFactory = new FakeMediaSourceFactory();
+    ProgressiveMediaSource.Factory mediaSourceFactory =
+        new ProgressiveMediaSource.Factory(
+            new DefaultDataSource.Factory(ApplicationProvider.getApplicationContext()));
     DefaultPreloadManager preloadManager =
         new DefaultPreloadManager(
             targetPreloadStatusControl,
-            fakeMediaSourceFactory,
+            mediaSourceFactory,
             trackSelector,
             bandwidthMeter,
             rendererCapabilitiesListFactory,
@@ -182,44 +196,51 @@ public class DefaultPreloadManagerTest {
             Util.getCurrentOrMainLooper());
     MediaItem.Builder mediaItemBuilder = new MediaItem.Builder();
     MediaItem mediaItem0 =
-        mediaItemBuilder.setMediaId("mediaId0").setUri("http://exoplayer.dev/video0").build();
+        mediaItemBuilder
+            .setMediaId("mediaId0")
+            .setUri(Uri.parse("asset://android_asset/media/mp4/sample.mp4"))
+            .build();
     MediaItem mediaItem1 =
-        mediaItemBuilder.setMediaId("mediaId1").setUri("http://exoplayer.dev/video1").build();
+        mediaItemBuilder
+            .setMediaId("mediaId1")
+            .setUri(Uri.parse("asset://android_asset/media/mp4/sample.mp4"))
+            .build();
     MediaItem mediaItem2 =
-        mediaItemBuilder.setMediaId("mediaId2").setUri("http://exoplayer.dev/video2").build();
+        mediaItemBuilder
+            .setMediaId("mediaId2")
+            .setUri(Uri.parse("asset://android_asset/media/mp4/sample.mp4"))
+            .build();
     preloadManager.add(mediaItem0, /* rankingData= */ 0);
-    FakeMediaSource wrappedMediaSource0 = fakeMediaSourceFactory.getLastCreatedSource();
-    wrappedMediaSource0.setAllowPreparation(false);
     preloadManager.add(mediaItem1, /* rankingData= */ 1);
-    FakeMediaSource wrappedMediaSource1 = fakeMediaSourceFactory.getLastCreatedSource();
-    wrappedMediaSource1.setAllowPreparation(false);
     preloadManager.add(mediaItem2, /* rankingData= */ 2);
-    FakeMediaSource wrappedMediaSource2 = fakeMediaSourceFactory.getLastCreatedSource();
-    wrappedMediaSource2.setAllowPreparation(false);
 
     preloadManager.invalidate();
-    shadowOf(Looper.getMainLooper()).idle();
+    runMainLooperUntil(() -> targetPreloadStatusControlCallStates.size() == 3);
 
-    assertThat(targetPreloadStatusControlCallStates).containsExactly(0);
+    assertThat(targetPreloadStatusControlCallStates).containsExactly(0, 1, 2).inOrder();
-    wrappedMediaSource0.setAllowPreparation(true);
-    shadowOf(Looper.getMainLooper()).idle();
-    assertThat(targetPreloadStatusControlCallStates).containsExactly(0, 1).inOrder();
   }
 
   @Test
-  public void invalidate_withSettingCurrentPlayingIndex_sourcesPreloadedToTargetStatusesInOrder() {
+  public void invalidate_withSettingCurrentPlayingIndex_sourcesPreloadedToTargetStatusesInOrder()
+      throws Exception {
     ArrayList<Integer> targetPreloadStatusControlCallStates = new ArrayList<>();
+    AtomicInteger currentPlayingItemIndex = new AtomicInteger();
     TargetPreloadStatusControl<Integer> targetPreloadStatusControl =
         rankingData -> {
           targetPreloadStatusControlCallStates.add(rankingData);
-          return new DefaultPreloadManager.Status(
+          if (abs(rankingData - currentPlayingItemIndex.get()) == 1) {
-              DefaultPreloadManager.Status.STAGE_TIMELINE_REFRESHED);
+            return new DefaultPreloadManager.Status(STAGE_LOADED_TO_POSITION_MS, 100L);
+          } else {
+            return new DefaultPreloadManager.Status(STAGE_TIMELINE_REFRESHED);
+          }
         };
-    FakeMediaSourceFactory fakeMediaSourceFactory = new FakeMediaSourceFactory();
+    ProgressiveMediaSource.Factory mediaSourceFactory =
+        new ProgressiveMediaSource.Factory(
+            new DefaultDataSource.Factory(ApplicationProvider.getApplicationContext()));
     DefaultPreloadManager preloadManager =
         new DefaultPreloadManager(
             targetPreloadStatusControl,
-            fakeMediaSourceFactory,
+            mediaSourceFactory,
             trackSelector,
             bandwidthMeter,
             rendererCapabilitiesListFactory,
@@ -227,32 +248,33 @@ public class DefaultPreloadManagerTest {
             Util.getCurrentOrMainLooper());
     MediaItem.Builder mediaItemBuilder = new MediaItem.Builder();
     MediaItem mediaItem0 =
-        mediaItemBuilder.setMediaId("mediaId0").setUri("http://exoplayer.dev/video0").build();
+        mediaItemBuilder
+            .setMediaId("mediaId0")
+            .setUri(Uri.parse("asset://android_asset/media/mp4/sample.mp4"))
+            .build();
     MediaItem mediaItem1 =
-        mediaItemBuilder.setMediaId("mediaId1").setUri("http://exoplayer.dev/video1").build();
+        mediaItemBuilder
+            .setMediaId("mediaId1")
+            .setUri(Uri.parse("asset://android_asset/media/mp4/sample.mp4"))
+            .build();
     MediaItem mediaItem2 =
-        mediaItemBuilder.setMediaId("mediaId2").setUri("http://exoplayer.dev/video2").build();
+        mediaItemBuilder
+            .setMediaId("mediaId2")
+            .setUri(Uri.parse("asset://android_asset/media/mp4/sample.mp4"))
+            .build();
     preloadManager.add(mediaItem0, /* rankingData= */ 0);
-    FakeMediaSource wrappedMediaSource0 = fakeMediaSourceFactory.getLastCreatedSource();
-    wrappedMediaSource0.setAllowPreparation(false);
     preloadManager.add(mediaItem1, /* rankingData= */ 1);
-    FakeMediaSource wrappedMediaSource1 = fakeMediaSourceFactory.getLastCreatedSource();
-    wrappedMediaSource1.setAllowPreparation(false);
     preloadManager.add(mediaItem2, /* rankingData= */ 2);
-    FakeMediaSource wrappedMediaSource2 = fakeMediaSourceFactory.getLastCreatedSource();
-    wrappedMediaSource2.setAllowPreparation(false);
     PreloadMediaSource preloadMediaSource2 =
         (PreloadMediaSource) preloadManager.getMediaSource(mediaItem2);
     preloadMediaSource2.prepareSource(
         (source, timeline) -> {}, bandwidthMeter.getTransferListener(), PlayerId.UNSET);
     preloadManager.setCurrentPlayingIndex(2);
+    currentPlayingItemIndex.set(2);
 
     preloadManager.invalidate();
-    shadowOf(Looper.getMainLooper()).idle();
+    runMainLooperUntil(() -> targetPreloadStatusControlCallStates.size() == 3);
 
-    assertThat(targetPreloadStatusControlCallStates).containsExactly(2, 1);
-    wrappedMediaSource1.setAllowPreparation(true);
-    shadowOf(Looper.getMainLooper()).idle();
     assertThat(targetPreloadStatusControlCallStates).containsExactly(2, 1, 0).inOrder();
   }
 
@@ -262,8 +284,7 @@ public class DefaultPreloadManagerTest {
     TargetPreloadStatusControl<Integer> targetPreloadStatusControl =
         rankingData -> {
           targetPreloadStatusControlCallStates.add(rankingData);
-          return new DefaultPreloadManager.Status(
+          return new DefaultPreloadManager.Status(STAGE_TIMELINE_REFRESHED);
-              DefaultPreloadManager.Status.STAGE_TIMELINE_REFRESHED);
         };
     FakeMediaSourceFactory fakeMediaSourceFactory = new FakeMediaSourceFactory();
     DefaultPreloadManager preloadManager =
@@ -306,8 +327,7 @@ public class DefaultPreloadManagerTest {
     TargetPreloadStatusControl<Integer> targetPreloadStatusControl =
         rankingData -> {
           targetPreloadStatusControlCallStates.add(rankingData);
-          return new DefaultPreloadManager.Status(
+          return new DefaultPreloadManager.Status(STAGE_TIMELINE_REFRESHED);
-              DefaultPreloadManager.Status.STAGE_TIMELINE_REFRESHED);
         };
     FakeMediaSourceFactory fakeMediaSourceFactory = new FakeMediaSourceFactory();
     DefaultPreloadManager preloadManager =
@@ -374,11 +394,13 @@ public class DefaultPreloadManagerTest {
           targetPreloadStatusControlCallStates.add(rankingData);
           return null;
         };
-    FakeMediaSourceFactory fakeMediaSourceFactory = new FakeMediaSourceFactory();
+    ProgressiveMediaSource.Factory mediaSourceFactory =
+        new ProgressiveMediaSource.Factory(
+            new DefaultDataSource.Factory(ApplicationProvider.getApplicationContext()));
     DefaultPreloadManager preloadManager =
         new DefaultPreloadManager(
             targetPreloadStatusControl,
-            fakeMediaSourceFactory,
+            mediaSourceFactory,
             trackSelector,
             bandwidthMeter,
             rendererCapabilitiesListFactory,
@@ -386,20 +408,23 @@ public class DefaultPreloadManagerTest {
             Util.getCurrentOrMainLooper());
     MediaItem.Builder mediaItemBuilder = new MediaItem.Builder();
     MediaItem mediaItem0 =
-        mediaItemBuilder.setMediaId("mediaId0").setUri("http://exoplayer.dev/video0").build();
+        mediaItemBuilder
+            .setMediaId("mediaId0")
+            .setUri(Uri.parse("asset://android_asset/media/mp4/sample.mp4"))
+            .build();
     MediaItem mediaItem1 =
-        mediaItemBuilder.setMediaId("mediaId1").setUri("http://exoplayer.dev/video1").build();
+        mediaItemBuilder
+            .setMediaId("mediaId1")
+            .setUri(Uri.parse("asset://android_asset/media/mp4/sample.mp4"))
+            .build();
     MediaItem mediaItem2 =
-        mediaItemBuilder.setMediaId("mediaId2").setUri("http://exoplayer.dev/video2").build();
+        mediaItemBuilder
+            .setMediaId("mediaId2")
+            .setUri(Uri.parse("asset://android_asset/media/mp4/sample.mp4"))
+            .build();
     preloadManager.add(mediaItem0, /* rankingData= */ 0);
-    FakeMediaSource wrappedMediaSource0 = fakeMediaSourceFactory.getLastCreatedSource();
-    wrappedMediaSource0.setAllowPreparation(false);
     preloadManager.add(mediaItem1, /* rankingData= */ 1);
-    FakeMediaSource wrappedMediaSource1 = fakeMediaSourceFactory.getLastCreatedSource();
-    wrappedMediaSource1.setAllowPreparation(false);
     preloadManager.add(mediaItem2, /* rankingData= */ 2);
-    FakeMediaSource wrappedMediaSource2 = fakeMediaSourceFactory.getLastCreatedSource();
-    wrappedMediaSource2.setAllowPreparation(false);
 
     preloadManager.invalidate();
     shadowOf(Looper.getMainLooper()).idle();
@@ -410,8 +435,7 @@ public class DefaultPreloadManagerTest {
   @Test
   public void removeByMediaItems_correspondingHeldSourceRemovedAndReleased() {
     TargetPreloadStatusControl<Integer> targetPreloadStatusControl =
-        rankingData ->
+        rankingData -> new DefaultPreloadManager.Status(STAGE_TIMELINE_REFRESHED);
-            new DefaultPreloadManager.Status(DefaultPreloadManager.Status.STAGE_TIMELINE_REFRESHED);
     MediaSource.Factory mockMediaSourceFactory = mock(MediaSource.Factory.class);
     DefaultPreloadManager preloadManager =
         new DefaultPreloadManager(
@@ -462,8 +486,7 @@ public class DefaultPreloadManagerTest {
   @Test
   public void removeByMediaSources_heldSourceRemovedAndReleased() {
     TargetPreloadStatusControl<Integer> targetPreloadStatusControl =
-        rankingData ->
+        rankingData -> new DefaultPreloadManager.Status(STAGE_TIMELINE_REFRESHED);
-            new DefaultPreloadManager.Status(DefaultPreloadManager.Status.STAGE_TIMELINE_REFRESHED);
     MediaSource.Factory mockMediaSourceFactory = mock(MediaSource.Factory.class);
     DefaultPreloadManager preloadManager =
         new DefaultPreloadManager(
@@ -521,8 +544,7 @@ public class DefaultPreloadManagerTest {
   @Test
   public void reset_returnZeroCount_sourcesButNotRendererCapabilitiesListReleased() {
     TargetPreloadStatusControl<Integer> targetPreloadStatusControl =
-        rankingData ->
+        rankingData -> new DefaultPreloadManager.Status(STAGE_TIMELINE_REFRESHED);
-            new DefaultPreloadManager.Status(DefaultPreloadManager.Status.STAGE_TIMELINE_REFRESHED);
     MediaSource.Factory mockMediaSourceFactory = mock(MediaSource.Factory.class);
     List<FakeRenderer> underlyingRenderers = new ArrayList<>();
     RenderersFactory renderersFactory =
@@ -593,8 +615,7 @@ public class DefaultPreloadManagerTest {
   @Test
   public void release_returnZeroCount_sourcesAndRendererCapabilitiesListReleased() {
     TargetPreloadStatusControl<Integer> targetPreloadStatusControl =
-        rankingData ->
+        rankingData -> new DefaultPreloadManager.Status(STAGE_TIMELINE_REFRESHED);
-            new DefaultPreloadManager.Status(DefaultPreloadManager.Status.STAGE_TIMELINE_REFRESHED);
     MediaSource.Factory mockMediaSourceFactory = mock(MediaSource.Factory.class);
     List<FakeRenderer> underlyingRenderers = new ArrayList<>();
     RenderersFactory renderersFactory =

libraries/exoplayer/src/test/java/androidx/media3/exoplayer/source/preload/PreloadMediaSourceTest.java

@@ -362,6 +362,80 @@ public final class PreloadMediaSourceTest {
     assertThat(onUsedByPlayerCalled.get()).isTrue();
   }
 
+  @Test
+  public void preload_loadToTheEndOfSource() throws Exception {
+    AtomicBoolean onTimelineRefreshedCalled = new AtomicBoolean();
+    AtomicBoolean onPreparedCalled = new AtomicBoolean();
+    AtomicBoolean onContinueLoadingRequestedCalled = new AtomicBoolean();
+    AtomicBoolean onLoadedToTheEndOfSourceCalled = new AtomicBoolean();
+    AtomicBoolean onUsedByPlayerCalled = new AtomicBoolean();
+    PreloadMediaSource.PreloadControl preloadControl =
+        new PreloadMediaSource.PreloadControl() {
+          @Override
+          public boolean onTimelineRefreshed(PreloadMediaSource mediaSource) {
+            onTimelineRefreshedCalled.set(true);
+            return true;
+          }
+
+          @Override
+          public boolean onPrepared(PreloadMediaSource mediaSource) {
+            onPreparedCalled.set(true);
+            return true;
+          }
+
+          @Override
+          public boolean onContinueLoadingRequested(
+              PreloadMediaSource mediaSource, long bufferedPositionUs) {
+            // In fact, this method is not necessarily to be called if the
+            // LOADING_CHECK_INTERVAL_BYTES set for the ProgressiveMediaSource.Factory is large
+            // enough to have the media load to the end in one round. However, since we explicitly
+            // set with a small value below, we will still expect this method to be called for at
+            // least once.
+            onContinueLoadingRequestedCalled.set(true);
+            return true;
+          }
+
+          @Override
+          public void onUsedByPlayer(PreloadMediaSource mediaSource) {
+            onUsedByPlayerCalled.set(true);
+          }
+
+          @Override
+          public void onLoadedToTheEndOfSource(PreloadMediaSource mediaSource) {
+            onLoadedToTheEndOfSourceCalled.set(true);
+          }
+        };
+    ProgressiveMediaSource.Factory mediaSourceFactory =
+        new ProgressiveMediaSource.Factory(
+            new DefaultDataSource.Factory(ApplicationProvider.getApplicationContext()));
+    mediaSourceFactory.setContinueLoadingCheckIntervalBytes(LOADING_CHECK_INTERVAL_BYTES);
+    TrackSelector trackSelector =
+        new DefaultTrackSelector(ApplicationProvider.getApplicationContext());
+    trackSelector.init(() -> {}, bandwidthMeter);
+    PreloadMediaSource.Factory preloadMediaSourceFactory =
+        new PreloadMediaSource.Factory(
+            mediaSourceFactory,
+            preloadControl,
+            trackSelector,
+            bandwidthMeter,
+            getRendererCapabilities(renderersFactory),
+            allocator,
+            Util.getCurrentOrMainLooper());
+    PreloadMediaSource preloadMediaSource =
+        preloadMediaSourceFactory.createMediaSource(
+            new MediaItem.Builder()
+                .setUri(Uri.parse("asset://android_asset/media/mp4/sample.mp4"))
+                .build());
+
+    preloadMediaSource.preload(/* startPositionUs= */ 0L);
+    runMainLooperUntil(onLoadedToTheEndOfSourceCalled::get);
+
+    assertThat(onTimelineRefreshedCalled.get()).isTrue();
+    assertThat(onPreparedCalled.get()).isTrue();
+    assertThat(onContinueLoadingRequestedCalled.get()).isTrue();
+    assertThat(onUsedByPlayerCalled.get()).isFalse();
+  }
+
   @Test
   public void
       prepareSource_beforeSourceInfoRefreshedForPreloading_onlyInvokeExternalCallerOnSourceInfoRefreshed() {