Add TransformationException with initial subset of error codes.

TransformationException will be used for all errors that occur
during a transformation.

PiperOrigin-RevId: 416032504

library/transformer/src/main/java/com/google/android/exoplayer2/transformer/TransformationException.java

+/*
+ * Copyright 2021 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 java.lang.annotation.ElementType.FIELD;
+import static java.lang.annotation.ElementType.LOCAL_VARIABLE;
+import static java.lang.annotation.ElementType.METHOD;
+import static java.lang.annotation.ElementType.PARAMETER;
+import static java.lang.annotation.ElementType.TYPE_USE;
+
+import android.os.SystemClock;
+import androidx.annotation.IntDef;
+import androidx.annotation.Nullable;
+import com.google.android.exoplayer2.util.Clock;
+import com.google.android.exoplayer2.util.Util;
+import java.lang.annotation.Documented;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/** Thrown when a non-locally recoverable transformation failure occurs. */
+public final class TransformationException extends Exception {
+
+  /**
+   * Creates an instance for an unexpected exception.
+   *
+   * <p>If the exception is a runtime exception, error code {@link ERROR_CODE_FAILED_RUNTIME_CHECK}
+   * is used. Otherwise, the created instance has error code {@link ERROR_CODE_UNSPECIFIED}.
+   *
+   * @param cause The cause of the failure.
+   * @return The created instance.
+   */
+  public static TransformationException createForUnexpected(Exception cause) {
+    if (cause instanceof RuntimeException) {
+      return new TransformationException(
+          "Unexpected runtime error", cause, ERROR_CODE_FAILED_RUNTIME_CHECK);
+    }
+    return new TransformationException("Unexpected error", cause, ERROR_CODE_UNSPECIFIED);
+  }
+
+  /**
+   * Codes that identify causes of {@link Transformer} errors.
+   *
+   * <p>This list of errors may be extended in future versions.
+   */
+  @Documented
+  @Retention(RetentionPolicy.SOURCE)
+  @Target({FIELD, METHOD, PARAMETER, LOCAL_VARIABLE, TYPE_USE})
+  @IntDef(
+      open = true,
+      value = {
+        ERROR_CODE_UNSPECIFIED,
+        ERROR_CODE_FAILED_RUNTIME_CHECK,
+        ERROR_CODE_DECODER_INIT_FAILED,
+        ERROR_CODE_DECODING_FAILED,
+        ERROR_CODE_DECODING_FORMAT_UNSUPPORTED,
+        ERROR_CODE_ENCODER_INIT_FAILED,
+        ERROR_CODE_ENCODING_FAILED,
+        ERROR_CODE_ENCODING_FORMAT_UNSUPPORTED,
+        ERROR_CODE_GL_INIT_FAILED,
+        ERROR_CODE_GL_PROCESSING_FAILED,
+      })
+  public @interface ErrorCode {}
+
+  // Miscellaneous errors (1xxx).
+
+  /** Caused by an error whose cause could not be identified. */
+  public static final int ERROR_CODE_UNSPECIFIED = 1000;
+  /**
+   * Caused by a failed runtime check.
+   *
+   * <p>This can happen when transformer reaches an invalid state.
+   */
+  public static final int ERROR_CODE_FAILED_RUNTIME_CHECK = 1001;
+
+  // Decoding errors (2xxx).
+
+  /** Caused by a decoder initialization failure. */
+  public static final int ERROR_CODE_DECODER_INIT_FAILED = 2001;
+  /** Caused by a failure while trying to decode media samples. */
+  public static final int ERROR_CODE_DECODING_FAILED = 2002;
+  /** Caused by trying to decode content whose format is not supported. */
+  public static final int ERROR_CODE_DECODING_FORMAT_UNSUPPORTED = 2003;
+
+  // Encoding errors (3xxx).
+
+  /** Caused by an encoder initialization failure. */
+  public static final int ERROR_CODE_ENCODER_INIT_FAILED = 3001;
+  /** Caused by a failure while trying to encode media samples. */
+  public static final int ERROR_CODE_ENCODING_FAILED = 3002;
+  /** Caused by requesting to encode content in a format that is not supported by the device. */
+  public static final int ERROR_CODE_ENCODING_FORMAT_UNSUPPORTED = 3003;
+
+  // GL errors (4xxx).
+
+  /** Caused by a GL initialization failure. */
+  public static final int ERROR_CODE_GL_INIT_FAILED = 4001;
+  /** Caused by a failure while using or releasing a GL program. */
+  public static final int ERROR_CODE_GL_PROCESSING_FAILED = 4002;
+
+  /** Returns the name of a given {@code errorCode}. */
+  public static String getErrorCodeName(@ErrorCode int errorCode) {
+    switch (errorCode) {
+      case ERROR_CODE_UNSPECIFIED:
+        return "ERROR_CODE_UNSPECIFIED";
+      case ERROR_CODE_FAILED_RUNTIME_CHECK:
+        return "ERROR_CODE_FAILED_RUNTIME_CHECK";
+      case ERROR_CODE_DECODER_INIT_FAILED:
+        return "ERROR_CODE_DECODER_INIT_FAILED";
+      case ERROR_CODE_DECODING_FAILED:
+        return "ERROR_CODE_DECODING_FAILED";
+      case ERROR_CODE_DECODING_FORMAT_UNSUPPORTED:
+        return "ERROR_CODE_DECODING_FORMAT_UNSUPPORTED";
+      case ERROR_CODE_ENCODER_INIT_FAILED:
+        return "ERROR_CODE_ENCODER_INIT_FAILED";
+      case ERROR_CODE_ENCODING_FAILED:
+        return "ERROR_CODE_ENCODING_FAILED";
+      case ERROR_CODE_ENCODING_FORMAT_UNSUPPORTED:
+        return "ERROR_CODE_ENCODING_FORMAT_UNSUPPORTED";
+      case ERROR_CODE_GL_INIT_FAILED:
+        return "ERROR_CODE_GL_INIT_FAILED";
+      case ERROR_CODE_GL_PROCESSING_FAILED:
+        return "ERROR_CODE_GL_PROCESSING_FAILED";
+      default:
+        return "invalid error code";
+    }
+  }
+
+  /**
+   * Equivalent to {@link TransformationException#getErrorCodeName(int)
+   * TransformationException.getErrorCodeName(this.errorCode)}.
+   */
+  public final String getErrorCodeName() {
+    return getErrorCodeName(errorCode);
+  }
+
+  /** An error code which identifies the cause of the transformation failure. */
+  public final @ErrorCode int errorCode;
+
+  /** The value of {@link SystemClock#elapsedRealtime()} when this exception was created. */
+  public final long timestampMs;
+
+  /**
+   * Creates an instance.
+   *
+   * @param message See {@link #getMessage()}.
+   * @param cause See {@link #getCause()}.
+   * @param errorCode A number which identifies the cause of the error. May be one of the {@link
+   *     ErrorCode ErrorCodes}.
+   */
+  public TransformationException(
+      @Nullable String message, @Nullable Throwable cause, @ErrorCode int errorCode) {
+    super(message, cause);
+    this.errorCode = errorCode;
+    this.timestampMs = Clock.DEFAULT.elapsedRealtime();
+  }
+
+  /**
+   * Returns whether the error data associated to this exception equals the error data associated to
+   * {@code other}.
+   *
+   * <p>Note that this method does not compare the exceptions' stacktraces.
+   */
+  public boolean errorInfoEquals(@Nullable TransformationException other) {
+    if (this == other) {
+      return true;
+    }
+    if (other == null || getClass() != other.getClass()) {
+      return false;
+    }
+
+    @Nullable Throwable thisCause = getCause();
+    @Nullable Throwable thatCause = other.getCause();
+    if (thisCause != null && thatCause != null) {
+      if (!Util.areEqual(thisCause.getMessage(), thatCause.getMessage())) {
+        return false;
+      }
+      if (!Util.areEqual(thisCause.getClass(), thatCause.getClass())) {
+        return false;
+      }
+    } else if (thisCause != null || thatCause != null) {
+      return false;
+    }
+    return errorCode == other.errorCode
+        && Util.areEqual(getMessage(), other.getMessage())
+        && timestampMs == other.timestampMs;
+  }
+}

library/transformer/src/main/java/com/google/android/exoplayer2/transformer/Transformer.java

@@ -832,22 +832,37 @@ public final class Transformer {
 
     @Override
     public void onPlayerError(PlaybackException error) {
+      // TODO(internal b/209469847): Once TransformationException is used in transformer components,
+      // extract TransformationExceptions wrapped in the PlaybackExceptions here before passing them
+      // on.
       handleTransformationEnded(error);
     }
 
     private void handleTransformationEnded(@Nullable Exception exception) {
+      @Nullable Exception resourceReleaseException = null;
       try {
         releaseResources(/* forCancellation= */ false);
       } catch (IllegalStateException e) {
-        if (exception == null) {
-          exception = e;
-        }
+        // TODO(internal b/209469847): Use a TransformationException with a specific error code when
+        // the IllegalStateException is caused by the muxer.
+        resourceReleaseException = e;
       }
 
-      if (exception == null) {
+      if (exception == null && resourceReleaseException == null) {
         listener.onTransformationCompleted(mediaItem);
-      } else {
-        listener.onTransformationError(mediaItem, exception);
+        return;
+      }
+
+      if (exception != null) {
+        listener.onTransformationError(
+            mediaItem,
+            exception instanceof TransformationException
+                ? exception
+                : TransformationException.createForUnexpected(exception));
+      }
+      if (resourceReleaseException != null) {
+        listener.onTransformationError(
+            mediaItem, TransformationException.createForUnexpected(resourceReleaseException));
       }
     }
   }

library/transformer/src/test/java/com/google/android/exoplayer2/transformer/TransformerTest.java

@@ -240,8 +240,9 @@ public final class TransformerTest {
     transformer.startTransformation(mediaItem, outputPath);
     Exception exception = TransformerTestRunner.runUntilError(transformer);
 
-    assertThat(exception).isInstanceOf(ExoPlaybackException.class);
-    assertThat(exception).hasCauseThat().isInstanceOf(IOException.class);
+    assertThat(exception).isInstanceOf(TransformationException.class);
+    assertThat(exception).hasCauseThat().isInstanceOf(ExoPlaybackException.class);
+    assertThat(exception).hasCauseThat().hasCauseThat().isInstanceOf(IOException.class);
   }
 
   @Test
@@ -253,7 +254,8 @@ public final class TransformerTest {
     transformer.startTransformation(mediaItem, outputPath);
     Exception exception = TransformerTestRunner.runUntilError(transformer);
 
-    assertThat(exception).isInstanceOf(IllegalStateException.class);
+    assertThat(exception).isInstanceOf(TransformationException.class);
+    assertThat(exception).hasCauseThat().isInstanceOf(IllegalStateException.class);
   }
 
   @Test