From 7c980f12db734d595dce729d3ae734129e43c10d Mon Sep 17 00:00:00 2001 From: kimvde Date: Thu, 22 Dec 2022 08:54:10 +0000 Subject: [PATCH] Ensure AssetLoader callbacks are always called in the right order Before, it was possible for onDurationUs() and onAllTracksRegistered() to be called before onTrackAdded() because they are called from different threads. onDurationUs() and onAllTracksRegistered() are called from the Transformer internal thread, and onTrackAdded() is called from the playback thread. PiperOrigin-RevId: 497102556 --- .../transformer/ExoPlayerAssetLoader.java | 5 +- .../transformer/ExoPlayerAssetLoaderTest.java | 149 ++++++++++++++++++ 2 files changed, 153 insertions(+), 1 deletion(-) create mode 100644 library/transformer/src/test/java/com/google/android/exoplayer2/transformer/ExoPlayerAssetLoaderTest.java diff --git a/library/transformer/src/main/java/com/google/android/exoplayer2/transformer/ExoPlayerAssetLoader.java b/library/transformer/src/main/java/com/google/android/exoplayer2/transformer/ExoPlayerAssetLoader.java index 5122c3263a..c8fb3f7c71 100644 --- a/library/transformer/src/main/java/com/google/android/exoplayer2/transformer/ExoPlayerAssetLoader.java +++ b/library/transformer/src/main/java/com/google/android/exoplayer2/transformer/ExoPlayerAssetLoader.java @@ -235,7 +235,6 @@ public final class ExoPlayerAssetLoader implements AssetLoader { public void start() { player.setMediaItem(mediaItem); player.prepare(); - player.play(); progressState = PROGRESS_STATE_WAITING_FOR_AVAILABILITY; } @@ -355,9 +354,13 @@ public final class ExoPlayerAssetLoader implements AssetLoader { "The asset loader has no track to output.", /* cause= */ null, ERROR_CODE_FAILED_RUNTIME_CHECK)); + return; } else { assetLoaderListener.onTrackCount(trackCount); } + // Start the renderers after having registered all the tracks to make sure the AssetLoader + // listener callbacks are called in the right order. + player.play(); } @Override diff --git a/library/transformer/src/test/java/com/google/android/exoplayer2/transformer/ExoPlayerAssetLoaderTest.java b/library/transformer/src/test/java/com/google/android/exoplayer2/transformer/ExoPlayerAssetLoaderTest.java new file mode 100644 index 0000000000..9d1068c732 --- /dev/null +++ b/library/transformer/src/test/java/com/google/android/exoplayer2/transformer/ExoPlayerAssetLoaderTest.java @@ -0,0 +1,149 @@ +/* + * Copyright 2022 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.exoplayer2.transformer; + +import static com.google.android.exoplayer2.robolectric.RobolectricUtil.runLooperUntil; +import static com.google.common.truth.Truth.assertThat; + +import android.content.Context; +import android.os.Handler; +import android.os.HandlerThread; +import android.os.Looper; +import androidx.annotation.Nullable; +import androidx.test.core.app.ApplicationProvider; +import androidx.test.ext.junit.runners.AndroidJUnit4; +import com.google.android.exoplayer2.Format; +import com.google.android.exoplayer2.MediaItem; +import com.google.android.exoplayer2.decoder.DecoderInputBuffer; +import com.google.android.exoplayer2.util.Clock; +import java.time.Duration; +import java.util.concurrent.atomic.AtomicBoolean; +import java.util.concurrent.atomic.AtomicReference; +import org.junit.Test; +import org.junit.runner.RunWith; +import org.robolectric.shadows.ShadowSystemClock; + +/** Unit tests for {@link ExoPlayerAssetLoader}. */ +@RunWith(AndroidJUnit4.class) +public class ExoPlayerAssetLoaderTest { + + @Test + public void exoPlayerAssetLoader_callsListenerCallbacksInRightOrder() throws Exception { + HandlerThread assetLoaderThread = new HandlerThread("AssetLoaderThread"); + assetLoaderThread.start(); + Looper assetLoaderLooper = assetLoaderThread.getLooper(); + AtomicReference exceptionRef = new AtomicReference<>(); + AtomicBoolean isTrackAdded = new AtomicBoolean(); + AssetLoader.Listener listener = + new AssetLoader.Listener() { + + private volatile boolean isDurationSet; + private volatile boolean isTrackCountSet; + + @Override + public void onDurationUs(long durationUs) { + // Sleep to increase the chances of the test failing. + sleep(); + isDurationSet = true; + } + + @Override + public void onTrackCount(int trackCount) { + // Sleep to increase the chances of the test failing. + sleep(); + isTrackCountSet = true; + } + + @Override + public SamplePipeline.Input onTrackAdded( + Format format, + @AssetLoader.SupportedOutputTypes int supportedOutputTypes, + long streamStartPositionUs, + long streamOffsetUs) { + if (!isDurationSet) { + exceptionRef.set( + new IllegalStateException("onTrackAdded() called before onDurationUs()")); + } else if (!isTrackCountSet) { + exceptionRef.set( + new IllegalStateException("onTrackAdded() called before onTrackCount()")); + } + isTrackAdded.set(true); + return new FakeSamplePipelineInput(); + } + + @Override + public void onError(Exception e) { + exceptionRef.set(e); + } + + private void sleep() { + try { + Thread.sleep(10); + } catch (InterruptedException e) { + exceptionRef.set(e); + } + } + }; + // Use default clock so that messages sent on different threads are not always executed in the + // order in which they are received. + Clock clock = Clock.DEFAULT; + AssetLoader assetLoader = getAssetLoader(assetLoaderLooper, listener, clock); + + new Handler(assetLoaderLooper).post(assetLoader::start); + runLooperUntil( + Looper.myLooper(), + () -> { + ShadowSystemClock.advanceBy(Duration.ofMillis(10)); + return isTrackAdded.get() || exceptionRef.get() != null; + }); + + assertThat(exceptionRef.get()).isNull(); + } + + private static AssetLoader getAssetLoader( + Looper looper, AssetLoader.Listener listener, Clock clock) { + Context context = ApplicationProvider.getApplicationContext(); + MediaItem mediaItem = MediaItem.fromUri("asset:///media/mp4/sample.mp4"); + return new ExoPlayerAssetLoader.Factory() + .setContext(context) + .setMediaItem(mediaItem) + .setRemoveAudio(false) + .setRemoveVideo(false) + .setFlattenVideoForSlowMotion(false) + .setDecoderFactory(new DefaultDecoderFactory(context)) + .setLooper(looper) + .setListener(listener) + .setClock(clock) + .createAssetLoader(); + } + + private static final class FakeSamplePipelineInput implements SamplePipeline.Input { + + @Override + public boolean expectsDecodedData() { + return false; + } + + @Nullable + @Override + public DecoderInputBuffer dequeueInputBuffer() { + return null; + } + + @Override + public void queueInputBuffer() {} + } +}