* Futures.FutureCombiner#callAsync(AsyncCallable, java.util.concurrent.Executor)}.
 *
 * <p>Much like {@link java.util.concurrent.Callable}, but returning a {@link ListenableFuture}
 * result.
 *
 * @since 20.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface AsyncCallable<V extends @Nullable Object> {
  /**

    assertFalse(functionCalled.get());
  }

  public void testSubmitAsync_asyncCallable_error() throws InterruptedException {
    final Error error = new Error("deliberate");
    AsyncCallable<Integer> callable =
        new AsyncCallable<Integer>() {
          @Override
          public ListenableFuture<Integer> call() {
            throw error;
          }

          @Override
          public String call() throws Exception {
            return expected;
          }
        };

    AsyncCallable<String> asyncCallable =
        Callables.asAsyncCallable(callable, MoreExecutors.newDirectExecutorService());

    ListenableFuture<String> future = asyncCallable.call();
    assertSame(expected, future.get());
  }

  @J2ktIncompatible
  @GwtIncompatible

          @Override
          public String call() throws Exception {
            return expected;
          }
        };

    AsyncCallable<String> asyncCallable =
        Callables.asAsyncCallable(callable, MoreExecutors.newDirectExecutorService());

    ListenableFuture<String> future = asyncCallable.call();
    assertSame(expected, future.get());
  }

  @J2ktIncompatible
  @GwtIncompatible

    assertFalse(functionCalled.get());
  }

  public void testSubmitAsync_asyncCallable_error() throws InterruptedException {
    final Error error = new Error("deliberate");
    AsyncCallable<Integer> callable =
        new AsyncCallable<Integer>() {
          @Override
          public ListenableFuture<Integer> call() {
            throw error;
          }

  }

  @WeakOuter
  private final class AsyncCallableInterruptibleTask
      extends CombinedFutureInterruptibleTask<ListenableFuture<V>> {
    private final AsyncCallable<V> callable;

    AsyncCallableInterruptibleTask(AsyncCallable<V> callable, Executor listenerExecutor) {
      super(listenerExecutor);
      this.callable = checkNotNull(callable);
    }

    @Override

   * callable} or a callable that has begun to execute, but if the output future is cancelled before
   * {@link AsyncCallable#call()} is invoked, {@link AsyncCallable#call()} will not be invoked.
   */
  public <T extends @Nullable Object> ListenableFuture<T> submitAsync(
      AsyncCallable<T> callable, Executor executor) {
    checkNotNull(callable);
    checkNotNull(executor);

      @Override
      public Integer apply(Integer input) {
        return input + delta;
      }
    };
  }

  private static AsyncCallable<Integer> asyncAdd(
      final ListenableFuture<Integer> future, final int delta, final Executor executor) {
    return new AsyncCallable<Integer>() {
      @Override
      public ListenableFuture<Integer> call() throws Exception {

      @Override
      public Integer apply(Integer input) {
        return input + delta;
      }
    };
  }

  private static AsyncCallable<Integer> asyncAdd(
      final ListenableFuture<Integer> future, final int delta, final Executor executor) {
    return new AsyncCallable<Integer>() {
      @Override
      public ListenableFuture<Integer> call() throws Exception {

    }
  }

  @WeakOuter
  private final class TrustedFutureInterruptibleAsyncTask
      extends InterruptibleTask<ListenableFuture<V>> {
    private final AsyncCallable<V> callable;

    TrustedFutureInterruptibleAsyncTask(AsyncCallable<V> callable) {
      this.callable = checkNotNull(callable);
    }

    @Override
    final boolean isDone() {
      return TrustedListenableFutureTask.this.isDone();