Improve logging II

- Show renderers with no tracks in EventLogger track logging
- Log renderer names in EventLogger track logging
- Add useful message to ExoPlaybackException instances (including
  renderer name for renderer errors)

PiperOrigin-RevId: 302421616

extensions/av1/src/main/java/com/google/android/exoplayer2/ext/av1/Libgav1VideoRenderer.java

@@ -34,6 +34,7 @@ import com.google.android.exoplayer2.video.VideoRendererEventListener;
 /** Decodes and renders video using libgav1 decoder. */
 public class Libgav1VideoRenderer extends DecoderVideoRenderer {
 
+  private static final String TAG = "Libgav1VideoRenderer";
   private static final int DEFAULT_NUM_OF_INPUT_BUFFERS = 4;
   private static final int DEFAULT_NUM_OF_OUTPUT_BUFFERS = 4;
   /* Default size based on 720p resolution video compressed by a factor of two. */
@@ -106,6 +107,11 @@ public class Libgav1VideoRenderer extends DecoderVideoRenderer {
     this.numOutputBuffers = numOutputBuffers;
   }
 
+  @Override
+  public String getName() {
+    return TAG;
+  }
+
   @Override
   @Capabilities
   public final int supportsFormat(Format format) {

extensions/ffmpeg/src/main/java/com/google/android/exoplayer2/ext/ffmpeg/FfmpegAudioRenderer.java

@@ -32,6 +32,8 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 /** Decodes and renders audio using FFmpeg. */
 public final class FfmpegAudioRenderer extends DecoderAudioRenderer {
 
+  private static final String TAG = "FfmpegAudioRenderer";
+
   /** The number of input and output buffers. */
   private static final int NUM_BUFFERS = 16;
   /** The default input buffer size. */
@@ -88,6 +90,11 @@ public final class FfmpegAudioRenderer extends DecoderAudioRenderer {
     this.enableFloatOutput = enableFloatOutput;
   }
 
+  @Override
+  public String getName() {
+    return TAG;
+  }
+
   @Override
   @FormatSupport
   protected int supportsFormatInternal(Format format) {

extensions/ffmpeg/src/main/java/com/google/android/exoplayer2/ext/ffmpeg/FfmpegVideoRenderer.java

@@ -36,6 +36,8 @@ import com.google.android.exoplayer2.video.VideoRendererEventListener;
  */
 public final class FfmpegVideoRenderer extends DecoderVideoRenderer {
 
+  private static final String TAG = "FfmpegAudioRenderer";
+
   /**
    * Creates a new instance.
    *
@@ -56,6 +58,11 @@ public final class FfmpegVideoRenderer extends DecoderVideoRenderer {
     // TODO: Implement.
   }
 
+  @Override
+  public String getName() {
+    return TAG;
+  }
+
   @Override
   @RendererCapabilities.Capabilities
   public final int supportsFormat(Format format) {

extensions/flac/src/main/java/com/google/android/exoplayer2/ext/flac/LibflacAudioRenderer.java

@@ -34,6 +34,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 /** Decodes and renders audio using the native Flac decoder. */
 public final class LibflacAudioRenderer extends DecoderAudioRenderer {
 
+  private static final String TAG = "LibflacAudioRenderer";
   private static final int NUM_BUFFERS = 16;
 
   private @MonotonicNonNull FlacStreamMetadata streamMetadata;
@@ -71,6 +72,11 @@ public final class LibflacAudioRenderer extends DecoderAudioRenderer {
         audioSink);
   }
 
+  @Override
+  public String getName() {
+    return TAG;
+  }
+
   @Override
   @FormatSupport
   protected int supportsFormatInternal(Format format) {

extensions/opus/src/main/java/com/google/android/exoplayer2/ext/opus/LibopusAudioRenderer.java

@@ -28,6 +28,7 @@ import com.google.android.exoplayer2.util.MimeTypes;
 /** Decodes and renders audio using the native Opus decoder. */
 public class LibopusAudioRenderer extends DecoderAudioRenderer {
 
+  private static final String TAG = "LibopusAudioRenderer";
   /** The number of input and output buffers. */
   private static final int NUM_BUFFERS = 16;
   /** The default input buffer size. */
@@ -53,6 +54,11 @@ public class LibopusAudioRenderer extends DecoderAudioRenderer {
     super(eventHandler, eventListener, audioProcessors);
   }
 
+  @Override
+  public String getName() {
+    return TAG;
+  }
+
   @Override
   @FormatSupport
   protected int supportsFormatInternal(Format format) {

extensions/vp9/src/main/java/com/google/android/exoplayer2/ext/vp9/LibvpxVideoRenderer.java

@@ -33,6 +33,8 @@ import com.google.android.exoplayer2.video.VideoRendererEventListener;
 /** Decodes and renders video using the native VP9 decoder. */
 public class LibvpxVideoRenderer extends DecoderVideoRenderer {
 
+  private static final String TAG = "LibvpxVideoRenderer";
+
   /** The number of input buffers. */
   private final int numInputBuffers;
   /**
@@ -115,6 +117,11 @@ public class LibvpxVideoRenderer extends DecoderVideoRenderer {
     this.numOutputBuffers = numOutputBuffers;
   }
 
+  @Override
+  public String getName() {
+    return TAG;
+  }
+
   @Override
   @Capabilities
   public final int supportsFormat(Format format) {

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

@@ -330,7 +330,8 @@ public abstract class BaseRenderer implements Renderer, RendererCapabilities {
         throwRendererExceptionIsExecuting = false;
       }
     }
-    return ExoPlaybackException.createForRenderer(cause, getIndex(), format, formatSupport);
+    return ExoPlaybackException.createForRenderer(
+        cause, getName(), getIndex(), format, formatSupport);
   }
 
   /**

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

@@ -16,6 +16,7 @@
 package com.google.android.exoplayer2;
 
 import android.os.SystemClock;
+import android.text.TextUtils;
 import androidx.annotation.IntDef;
 import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.RendererCapabilities.FormatSupport;
@@ -70,9 +71,10 @@ public final class ExoPlaybackException extends Exception {
   /** The {@link Type} of the playback failure. */
   @Type public final int type;
 
-  /**
+  /** If {@link #type} is {@link #TYPE_RENDERER}, this is the name of the renderer. */
-   * If {@link #type} is {@link #TYPE_RENDERER}, this is the index of the renderer.
+  @Nullable public final String rendererName;
-   */
+
+  /** If {@link #type} is {@link #TYPE_RENDERER}, this is the index of the renderer. */
   public final int rendererIndex;
 
   /**
@@ -116,12 +118,15 @@ public final class ExoPlaybackException extends Exception {
    */
   public static ExoPlaybackException createForRenderer(
       Exception cause,
+      String rendererName,
       int rendererIndex,
       @Nullable Format rendererFormat,
       @FormatSupport int rendererFormatSupport) {
     return new ExoPlaybackException(
         TYPE_RENDERER,
         cause,
+        /* customMessage= */ null,
+        rendererName,
         rendererIndex,
         rendererFormat,
         rendererFormat == null ? RendererCapabilities.FORMAT_HANDLED : rendererFormatSupport);
@@ -161,6 +166,19 @@ public final class ExoPlaybackException extends Exception {
     this(
         type,
         cause,
+        /* customMessage= */ null,
+        /* rendererName= */ null,
+        /* rendererIndex= */ C.INDEX_UNSET,
+        /* rendererFormat= */ null,
+        /* rendererFormatSupport= */ RendererCapabilities.FORMAT_HANDLED);
+  }
+
+  private ExoPlaybackException(@Type int type, String message) {
+    this(
+        type,
+        /* cause= */ null,
+        /* customMessage= */ message,
+        /* rendererName= */ null,
         /* rendererIndex= */ C.INDEX_UNSET,
         /* rendererFormat= */ null,
         /* rendererFormatSupport= */ RendererCapabilities.FORMAT_HANDLED);
@@ -168,29 +186,30 @@ public final class ExoPlaybackException extends Exception {
 
   private ExoPlaybackException(
       @Type int type,
-      Throwable cause,
+      @Nullable Throwable cause,
+      @Nullable String customMessage,
+      @Nullable String rendererName,
       int rendererIndex,
       @Nullable Format rendererFormat,
       @FormatSupport int rendererFormatSupport) {
-    super(cause);
+    super(
+        deriveMessage(
+            type,
+            customMessage,
+            rendererName,
+            rendererIndex,
+            rendererFormat,
+            rendererFormatSupport),
+        cause);
     this.type = type;
     this.cause = cause;
+    this.rendererName = rendererName;
     this.rendererIndex = rendererIndex;
     this.rendererFormat = rendererFormat;
     this.rendererFormatSupport = rendererFormatSupport;
     timestampMs = SystemClock.elapsedRealtime();
   }
 
-  private ExoPlaybackException(@Type int type, String message) {
-    super(message);
-    this.type = type;
-    rendererIndex = C.INDEX_UNSET;
-    rendererFormat = null;
-    rendererFormatSupport = RendererCapabilities.FORMAT_UNSUPPORTED_TYPE;
-    cause = null;
-    timestampMs = SystemClock.elapsedRealtime();
-  }
-
   /**
    * Retrieves the underlying error when {@link #type} is {@link #TYPE_SOURCE}.
    *
@@ -230,4 +249,45 @@ public final class ExoPlaybackException extends Exception {
     Assertions.checkState(type == TYPE_OUT_OF_MEMORY);
     return (OutOfMemoryError) Assertions.checkNotNull(cause);
   }
+
+  @Nullable
+  private static String deriveMessage(
+      @Type int type,
+      @Nullable String customMessage,
+      @Nullable String rendererName,
+      int rendererIndex,
+      @Nullable Format rendererFormat,
+      @FormatSupport int rendererFormatSupport) {
+    @Nullable String message;
+    switch (type) {
+      case TYPE_SOURCE:
+        message = "Source error";
+        break;
+      case TYPE_RENDERER:
+        message =
+            rendererName
+                + " error"
+                + ", index="
+                + rendererIndex
+                + ", format="
+                + rendererFormat
+                + ", format_supported="
+                + RendererCapabilities.getFormatSupportString(rendererFormatSupport);
+        break;
+      case TYPE_REMOTE:
+        message = "Remote error";
+        break;
+      case TYPE_OUT_OF_MEMORY:
+        message = "Out of memory error";
+        break;
+      case TYPE_UNEXPECTED:
+      default:
+        message = "Unexpected runtime error";
+        break;
+    }
+    if (!TextUtils.isEmpty(customMessage)) {
+      message += ": " + customMessage;
+    }
+    return message;
+  }
 }

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

@@ -379,7 +379,6 @@ import java.util.concurrent.atomic.AtomicBoolean;
   // Handler.Callback implementation.
 
   @Override
-  @SuppressWarnings("unchecked")
   public boolean handleMessage(Message msg) {
     try {
       switch (msg.what) {
@@ -469,7 +468,7 @@ import java.util.concurrent.atomic.AtomicBoolean;
       }
       maybeNotifyPlaybackInfoChanged();
     } catch (ExoPlaybackException e) {
-      Log.e(TAG, getExoPlaybackExceptionMessage(e), e);
+      Log.e(TAG, "Playback error", e);
       stopInternal(
           /* forceResetRenderers= */ true,
           /* resetPositionAndState= */ false,
@@ -477,19 +476,20 @@ import java.util.concurrent.atomic.AtomicBoolean;
       playbackInfo = playbackInfo.copyWithPlaybackError(e);
       maybeNotifyPlaybackInfoChanged();
     } catch (IOException e) {
-      Log.e(TAG, "Source error", e);
+      ExoPlaybackException error = ExoPlaybackException.createForSource(e);
+      Log.e(TAG, "Playback error", error);
       stopInternal(
           /* forceResetRenderers= */ false,
           /* resetPositionAndState= */ false,
           /* acknowledgeStop= */ false);
-      playbackInfo = playbackInfo.copyWithPlaybackError(ExoPlaybackException.createForSource(e));
+      playbackInfo = playbackInfo.copyWithPlaybackError(error);
       maybeNotifyPlaybackInfoChanged();
     } catch (RuntimeException | OutOfMemoryError e) {
-      Log.e(TAG, "Internal runtime error", e);
       ExoPlaybackException error =
           e instanceof OutOfMemoryError
               ? ExoPlaybackException.createForOutOfMemoryError((OutOfMemoryError) e)
               : ExoPlaybackException.createForUnexpected((RuntimeException) e);
+      Log.e(TAG, "Playback error", error);
       stopInternal(
           /* forceResetRenderers= */ true,
           /* resetPositionAndState= */ false,
@@ -502,20 +502,6 @@ import java.util.concurrent.atomic.AtomicBoolean;
 
   // Private methods.
 
-  private String getExoPlaybackExceptionMessage(ExoPlaybackException e) {
-    if (e.type != ExoPlaybackException.TYPE_RENDERER) {
-      return "Playback error.";
-    }
-    return "Renderer error: index="
-        + e.rendererIndex
-        + ", type="
-        + Util.getTrackTypeString(renderers[e.rendererIndex].getTrackType())
-        + ", format="
-        + e.rendererFormat
-        + ", rendererSupport="
-        + RendererCapabilities.getFormatSupportString(e.rendererFormatSupport);
-  }
-
   /**
    * Blocks the current thread until {@link #releaseInternal()} is executed on the playback Thread.
    *

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

@@ -189,6 +189,14 @@ public interface Renderer extends PlayerMessage.Target {
    */
   int STATE_STARTED = 2;
 
+  /**
+   * Returns the name of this renderer, for logging and debugging purposes. Should typically be the
+   * renderer's (un-obfuscated) class name.
+   *
+   * @return The name of this renderer.
+   */
+  String getName();
+
   /**
    * Returns the track type that the renderer handles. For example, a video renderer will return
    * {@link C#TRACK_TYPE_VIDEO}, an audio renderer will return {@link C#TRACK_TYPE_AUDIO}, a text

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

@@ -260,6 +260,9 @@ public interface RendererCapabilities {
     }
   }
 
+  /** Returns the name of the {@link Renderer}. */
+  String getName();
+
   /**
    * Returns the track type that the {@link Renderer} handles. For example, a video renderer will
    * return {@link C#TRACK_TYPE_VIDEO}, an audio renderer will return {@link C#TRACK_TYPE_AUDIO}, a

library/core/src/main/java/com/google/android/exoplayer2/audio/MediaCodecAudioRenderer.java

@@ -201,11 +201,14 @@ public class MediaCodecAudioRenderer extends MediaCodecRenderer implements Media
     audioSink.setListener(new AudioSinkListener());
   }
 
+  @Override
+  public String getName() {
+    return TAG;
+  }
+
   @Override
   @Capabilities
-  protected int supportsFormat(
+  protected int supportsFormat(MediaCodecSelector mediaCodecSelector, Format format)
-      MediaCodecSelector mediaCodecSelector,
-      Format format)
       throws DecoderQueryException {
     String mimeType = format.sampleMimeType;
     if (!MimeTypes.isAudio(mimeType)) {

library/core/src/main/java/com/google/android/exoplayer2/metadata/MetadataRenderer.java

@@ -40,6 +40,7 @@ import org.checkerframework.checker.nullness.compatqual.NullableType;
  */
 public final class MetadataRenderer extends BaseRenderer implements Callback {
 
+  private static final String TAG = "MetadataRenderer";
   private static final int MSG_INVOKE_RENDERER = 0;
   // TODO: Holding multiple pending metadata objects is temporary mitigation against
   // https://github.com/google/ExoPlayer/issues/1874. It should be removed once this issue has been
@@ -92,6 +93,11 @@ public final class MetadataRenderer extends BaseRenderer implements Callback {
     pendingMetadataTimestamps = new long[MAX_PENDING_METADATA_COUNT];
   }
 
+  @Override
+  public String getName() {
+    return TAG;
+  }
+
   @Override
   @Capabilities
   public int supportsFormat(Format format) {

library/core/src/main/java/com/google/android/exoplayer2/text/TextRenderer.java

@@ -121,6 +121,11 @@ public final class TextRenderer extends BaseRenderer implements Callback {
     formatHolder = new FormatHolder();
   }
 
+  @Override
+  public String getName() {
+    return TAG;
+  }
+
   @Override
   @Capabilities
   public int supportsFormat(Format format) {

library/core/src/main/java/com/google/android/exoplayer2/trackselection/MappingTrackSelector.java

@@ -92,6 +92,7 @@ public abstract class MappingTrackSelector extends TrackSelector {
     @Deprecated public final int length;
 
     private final int rendererCount;
+    private final String[] rendererNames;
     private final int[] rendererTrackTypes;
     private final TrackGroupArray[] rendererTrackGroups;
     @AdaptiveSupport private final int[] rendererMixedMimeTypeAdaptiveSupports;
@@ -99,6 +100,7 @@ public abstract class MappingTrackSelector extends TrackSelector {
     private final TrackGroupArray unmappedTrackGroups;
 
     /**
+     * @param rendererNames The name of each renderer.
      * @param rendererTrackTypes The track type handled by each renderer.
      * @param rendererTrackGroups The {@link TrackGroup}s mapped to each renderer.
      * @param rendererMixedMimeTypeAdaptiveSupports The {@link AdaptiveSupport} for mixed MIME type
@@ -109,11 +111,13 @@ public abstract class MappingTrackSelector extends TrackSelector {
      */
     @SuppressWarnings("deprecation")
     /* package */ MappedTrackInfo(
+        String[] rendererNames,
         int[] rendererTrackTypes,
         TrackGroupArray[] rendererTrackGroups,
         @AdaptiveSupport int[] rendererMixedMimeTypeAdaptiveSupports,
         @Capabilities int[][][] rendererFormatSupports,
         TrackGroupArray unmappedTrackGroups) {
+      this.rendererNames = rendererNames;
       this.rendererTrackTypes = rendererTrackTypes;
       this.rendererTrackGroups = rendererTrackGroups;
       this.rendererFormatSupports = rendererFormatSupports;
@@ -128,6 +132,17 @@ public abstract class MappingTrackSelector extends TrackSelector {
       return rendererCount;
     }
 
+    /**
+     * Returns the name of the renderer at a given index.
+     *
+     * @see Renderer#getName()
+     * @param rendererIndex The renderer index.
+     * @return The name of the renderer.
+     */
+    public String getRendererName(int rendererIndex) {
+      return rendererNames[rendererIndex];
+    }
+
     /**
      * Returns the track type that the renderer at a given index handles.
      *
@@ -380,6 +395,7 @@ public abstract class MappingTrackSelector extends TrackSelector {
 
     // Create a track group array for each renderer, and trim each rendererFormatSupports entry.
     TrackGroupArray[] rendererTrackGroupArrays = new TrackGroupArray[rendererCapabilities.length];
+    String[] rendererNames = new String[rendererCapabilities.length];
     int[] rendererTrackTypes = new int[rendererCapabilities.length];
     for (int i = 0; i < rendererCapabilities.length; i++) {
       int rendererTrackGroupCount = rendererTrackGroupCounts[i];
@@ -388,6 +404,7 @@ public abstract class MappingTrackSelector extends TrackSelector {
               Util.nullSafeArrayCopy(rendererTrackGroups[i], rendererTrackGroupCount));
       rendererFormatSupports[i] =
           Util.nullSafeArrayCopy(rendererFormatSupports[i], rendererTrackGroupCount);
+      rendererNames[i] = rendererCapabilities[i].getName();
       rendererTrackTypes[i] = rendererCapabilities[i].getTrackType();
     }
 
@@ -401,6 +418,7 @@ public abstract class MappingTrackSelector extends TrackSelector {
     // Package up the track information and selections.
     MappedTrackInfo mappedTrackInfo =
         new MappedTrackInfo(
+            rendererNames,
             rendererTrackTypes,
             rendererTrackGroupArrays,
             rendererMixedMimeTypeAdaptationSupports,

library/core/src/main/java/com/google/android/exoplayer2/util/EventLogger.java

@@ -216,8 +216,10 @@ public class EventLogger implements AnalyticsListener {
     for (int rendererIndex = 0; rendererIndex < rendererCount; rendererIndex++) {
       TrackGroupArray rendererTrackGroups = mappedTrackInfo.getTrackGroups(rendererIndex);
       TrackSelection trackSelection = trackSelections.get(rendererIndex);
-      if (rendererTrackGroups.length > 0) {
+      if (rendererTrackGroups.length == 0) {
-        logd("  Renderer:" + rendererIndex + " [");
+        logd("  " + mappedTrackInfo.getRendererName(rendererIndex) + " []");
+      } else {
+        logd("  " + mappedTrackInfo.getRendererName(rendererIndex) + " [");
         for (int groupIndex = 0; groupIndex < rendererTrackGroups.length; groupIndex++) {
           TrackGroup trackGroup = rendererTrackGroups.get(groupIndex);
           String adaptiveSupport =
@@ -261,7 +263,7 @@ public class EventLogger implements AnalyticsListener {
     // Log tracks not associated with a renderer.
     TrackGroupArray unassociatedTrackGroups = mappedTrackInfo.getUnmappedTrackGroups();
     if (unassociatedTrackGroups.length > 0) {
-      logd("  Renderer:None [");
+      logd("  Unmapped [");
       for (int groupIndex = 0; groupIndex < unassociatedTrackGroups.length; groupIndex++) {
         logd("    Group:" + groupIndex + " [");
         TrackGroup trackGroup = unassociatedTrackGroups.get(groupIndex);

library/core/src/main/java/com/google/android/exoplayer2/video/MediaCodecVideoRenderer.java

@@ -240,11 +240,14 @@ public class MediaCodecVideoRenderer extends MediaCodecRenderer {
     clearReportedVideoSize();
   }
 
+  @Override
+  public String getName() {
+    return TAG;
+  }
+
   @Override
   @Capabilities
-  protected int supportsFormat(
+  protected int supportsFormat(MediaCodecSelector mediaCodecSelector, Format format)
-      MediaCodecSelector mediaCodecSelector,
-      Format format)
       throws DecoderQueryException {
     String mimeType = format.sampleMimeType;
     if (!MimeTypes.isVideo(mimeType)) {

library/core/src/main/java/com/google/android/exoplayer2/video/spherical/CameraMotionRenderer.java

@@ -33,6 +33,7 @@ import java.nio.ByteBuffer;
 /** A {@link Renderer} that parses the camera motion track. */
 public class CameraMotionRenderer extends BaseRenderer {
 
+  private static final String TAG = "CameraMotionRenderer";
   // The amount of time to read samples ahead of the current time.
   private static final int SAMPLE_WINDOW_DURATION_US = 100000;
 
@@ -49,6 +50,11 @@ public class CameraMotionRenderer extends BaseRenderer {
     scratch = new ParsableByteArray();
   }
 
+  @Override
+  public String getName() {
+    return TAG;
+  }
+
   @Override
   @Capabilities
   public int supportsFormat(Format format) {

library/core/src/test/java/com/google/android/exoplayer2/audio/DecoderAudioRendererTest.java

@@ -58,6 +58,11 @@ public class DecoderAudioRendererTest {
     MockitoAnnotations.initMocks(this);
     audioRenderer =
         new DecoderAudioRenderer(null, null, mockAudioSink) {
+          @Override
+          public String getName() {
+            return "TestAudioRenderer";
+          }
+
           @Override
           @FormatSupport
           protected int supportsFormatInternal(Format format) {

library/core/src/test/java/com/google/android/exoplayer2/trackselection/DefaultTrackSelectorTest.java

@@ -49,6 +49,7 @@ import com.google.android.exoplayer2.trackselection.DefaultTrackSelector.Selecti
 import com.google.android.exoplayer2.trackselection.TrackSelector.InvalidationListener;
 import com.google.android.exoplayer2.upstream.BandwidthMeter;
 import com.google.android.exoplayer2.util.MimeTypes;
+import com.google.android.exoplayer2.util.Util;
 import java.util.HashMap;
 import java.util.Map;
 import org.junit.Before;
@@ -1546,6 +1547,11 @@ public final class DefaultTrackSelectorTest {
       this.supportValue = supportValue;
     }
 
+    @Override
+    public String getName() {
+      return "FakeRenderer(" + Util.getTrackTypeString(trackType) + ")";
+    }
+
     @Override
     public int getTrackType() {
       return trackType;
@@ -1590,6 +1596,11 @@ public final class DefaultTrackSelectorTest {
       this.formatToCapability = new HashMap<>(formatToCapability);
     }
 
+    @Override
+    public String getName() {
+      return "FakeRenderer(" + Util.getTrackTypeString(trackType) + ")";
+    }
+
     @Override
     public int getTrackType() {
       return trackType;

library/core/src/test/java/com/google/android/exoplayer2/trackselection/MappingTrackSelectorTest.java

@@ -32,6 +32,7 @@ import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
 import com.google.android.exoplayer2.testutil.FakeTimeline;
 import com.google.android.exoplayer2.util.MimeTypes;
+import com.google.android.exoplayer2.util.Util;
 import org.junit.BeforeClass;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -169,6 +170,11 @@ public final class MappingTrackSelectorTest {
       this.trackType = trackType;
     }
 
+    @Override
+    public String getName() {
+      return "FakeRenderer(" + Util.getTrackTypeString(trackType) + ")";
+    }
+
     @Override
     public int getTrackType() {
       return trackType;

library/core/src/test/java/com/google/android/exoplayer2/video/DecoderVideoRendererTest.java

@@ -80,6 +80,11 @@ public final class DecoderVideoRendererTest {
 
           @C.VideoOutputMode private int outputMode;
 
+          @Override
+          public String getName() {
+            return "TestVideoRenderer";
+          }
+
           @Override
           @Capabilities
           public int supportsFormat(Format format) {

playbacktests/src/androidTest/java/com/google/android/exoplayer2/playbacktests/gts/DebugRenderersFactory.java

@@ -72,6 +72,7 @@ import java.util.ArrayList;
    */
   private static class DebugMediaCodecVideoRenderer extends MediaCodecVideoRenderer {
 
+    private static final String TAG = "DebugMediaCodecVideoRenderer";
     private static final int ARRAY_SIZE = 1000;
 
     private final long[] timestampsList = new long[ARRAY_SIZE];
@@ -98,6 +99,11 @@ import java.util.ArrayList;
           maxDroppedFrameCountToNotify);
     }
 
+    @Override
+    public String getName() {
+      return TAG;
+    }
+
     @Override
     protected void configureCodec(
         MediaCodecInfo codecInfo,

testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeRenderer.java

@@ -39,6 +39,7 @@ import java.util.List;
  */
 public class FakeRenderer extends BaseRenderer {
 
+  private static final String TAG = "FakeRenderer";
   /**
    * The amount of time ahead of the current playback position that the renderer reads from the
    * source. A real renderer will typically read ahead by a small amount due to pipelining through
@@ -64,6 +65,11 @@ public class FakeRenderer extends BaseRenderer {
     formatsRead = new ArrayList<>();
   }
 
+  @Override
+  public String getName() {
+    return TAG;
+  }
+
   @Override
   protected void onPositionReset(long positionUs, boolean joining) throws ExoPlaybackException {
     playbackPositionUs = positionUs;
@@ -93,6 +99,7 @@ public class FakeRenderer extends BaseRenderer {
                     Util.formatInvariant(
                         "Format track type (%s) doesn't match renderer track type (%s).",
                         MimeTypes.getTrackType(format.sampleMimeType), getTrackType())),
+                getName(),
                 getIndex(),
                 format,
                 FORMAT_UNSUPPORTED_TYPE);