}

    return JavaLittleEndianBytes.INSTANCE;
  }

  // Compare AbstractFuture.VarHandleAtomicHelperMaker.
  private enum VarHandleLittleEndianBytesMaker {
    INSTANCE {
      /**
       * Implementation used by non-J2ObjC environments (aside, of course, from those that have
       * supersource for the entirety of {@link AbstractFuture}).
       */
      @Override
      @J2ObjCIncompatible

 * SettableFuture}).
 *
 * <p>Useful for testing the behavior of Future utilities against odd futures.
 *
 * @author Anthony Zana
 */
@GwtCompatible
@NullUnmarked
final class UncheckedThrowingFuture<V> extends AbstractFuture<V> {

  public static <V> ListenableFuture<V> throwingError(Error error) {
    UncheckedThrowingFuture<V> future = new UncheckedThrowingFuture<V>();
    future.complete(checkNotNull(error));
    return future;
  }

          }
        };
      }
    },
    ABSTRACT_FUTURE {
      @Override
      ExecutionListWrapper newExecutionList() {
        return new ExecutionListWrapper() {
          final AbstractFuture<?> future = new AbstractFuture<Object>() {};

          @Override
          public void add(Runnable runnable, Executor executor) {
            future.addListener(runnable, executor);
          }

          @Override

     * versions of Java, and apparently Unsafe can cause SIGSEGV instead of NPE—almost as if it's
     * not safe.
     */
    concat(
            stream(AbstractFuture.class.getDeclaredMethods()),
            stream(requireNonNull(AbstractFuture.class.getSuperclass()).getDeclaredMethods()))
        .filter(
            m ->
                m.getName().equals("getDoneValue")

  /**
   * A less abstract subclass of AbstractFuture. This can be used to optimize setFuture by ensuring
   * that {@link #get} calls exactly the implementation of {@link AbstractFuture#get}.
   */
  abstract static class TrustedFuture<V extends @Nullable Object> extends FluentFuture<V>
      implements AbstractFuture.Trusted<V> {
    @CanIgnoreReturnValue
    @Override
    @ParametricNullness

    InCompletionOrderState<T> state = new InCompletionOrderState<>(copy);
    ImmutableList.Builder<AbstractFuture<T>> delegatesBuilder =
        ImmutableList.builderWithExpectedSize(copy.length);
    for (int i = 0; i < copy.length; i++) {
      delegatesBuilder.add(new InCompletionOrderFuture<T>(state));
    }

    ImmutableList<AbstractFuture<T>> delegates = delegatesBuilder.build();
    for (int i = 0; i < copy.length; i++) {

 *   <li>Decrements a counter atomically
 * </ul>
 */
@GwtCompatible
@ReflectionSupport(value = ReflectionSupport.Level.FULL)
abstract class AggregateFutureState<OutputT extends @Nullable Object>
    extends AbstractFuture.TrustedFuture<OutputT> {
  /*
   * The following fields are package-private, even though we intend never to use them outside this
   * file. For discussion, see AbstractFutureState.
   */

      if (Modifier.isPublic(method.getModifiers())
          && method.getName().startsWith("test")
          /*
           * When we block access to AtomicReferenceFieldUpdater, we can't even reflect on
           * AbstractFuture, since it declares methods that use that type in their signatures.
           */
          && !method.getName().equals("testFutures_nullChecks")) {
        suite.addTest(
            TestSuite.createTest(

        return object.toString();
      }
    };
  }

  public void testCancellationDuringReentrancy() throws Exception {
    TestLogHandler logHandler = new TestLogHandler();
    Logger.getLogger(AbstractFuture.class.getName()).addHandler(logHandler);

    List<Future<?>> results = new ArrayList<>();
    Runnable[] manualExecutorTask = new Runnable[1];
    Executor manualExecutor =
        new Executor() {