}
    }

    abstract void setValue(@ParametricNullness T value);
  }

  @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);