content: /*
   * Copyright (C) 2014 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 android.util;
  
  import android.annotation.NonNull;
  import android.annotation.Nullable;
  import android.os.ParcelableException;
  
  import com.android.internal.util.Preconditions;
  
  import java.io.IOException;
  
  /**
   * Utility methods for proxying richer exceptions across Binder calls.
   *
   * @hide
   */
  public class ExceptionUtils {
      public static RuntimeException wrap(IOException e) {
          throw new ParcelableException(e);
      }
  
      public static void maybeUnwrapIOException(RuntimeException e) throws IOException {
          if (e instanceof ParcelableException) {
              ((ParcelableException) e).maybeRethrow(IOException.class);
          }
      }
  
      public static String getCompleteMessage(String msg, Throwable t) {
          final StringBuilder builder = new StringBuilder();
          if (msg != null) {
              builder.append(msg).append(": ");
          }
          builder.append(t.getMessage());
          while ((t = t.getCause()) != null) {
              builder.append(": ").append(t.getMessage());
          }
          return builder.toString();
      }
  
      public static String getCompleteMessage(Throwable t) {
          return getCompleteMessage(null, t);
      }
  
      public static <E extends Throwable> void propagateIfInstanceOf(
              @Nullable Throwable t, Class<E> c) throws E {
          if (t != null && c.isInstance(t)) {
              throw c.cast(t);
          }
      }
  
      /**
       * @param <E> a checked exception that is ok to throw without wrapping
       */
      public static <E extends Exception> RuntimeException propagate(@NonNull Throwable t, Class<E> c)
              throws E {
          propagateIfInstanceOf(t, c);
          return propagate(t);
      }
  
      public static RuntimeException propagate(@NonNull Throwable t) {
          Preconditions.checkNotNull(t);
          propagateIfInstanceOf(t, Error.class);
          propagateIfInstanceOf(t, RuntimeException.class);
          throw new RuntimeException(t);
      }
  
      /**
       * Gets the root {@link Throwable#getCause() cause} of {@code t}
       */
      public static @NonNull Throwable getRootCause(@NonNull Throwable t) {
          while (t.getCause() != null) t = t.getCause();
          return t;
      }
  
      /**
       * Appends {@code cause} at the end of the causal chain of {@code t}
       *
       * @return {@code t} for convenience
       */
      public static @NonNull Throwable appendCause(@NonNull Throwable t, @Nullable Throwable cause) {
          if (cause != null) {
              getRootCause(t).initCause(cause);
          }
          return t;
      }
  }