Class<X> exceptionType,
      Function<? super X, ? extends V> fallback,
      Executor executor) {
    CatchingFuture<V, X> future = new CatchingFuture<>(input, exceptionType, fallback);
    input.addListener(future, rejectionPropagatingExecutor(executor, future));
    return future;
  }

  static <X extends Throwable, V extends @Nullable Object> ListenableFuture<V> createAsync(
      ListenableFuture<? extends V> input,

   *
   * <p>When selecting an executor, note that {@code directExecutor} is dangerous in some cases. See
   * the discussion in the {@link ListenableFuture#addListener ListenableFuture.addListener}
   * documentation.
   */
  public void add(Runnable runnable, Executor executor) {
    // Fail fast on a null. We throw NPE here because the contract of Executor states that it throws

      AsyncFunction<? super I, ? extends O> function,
      Executor executor) {
    checkNotNull(executor);
    AsyncTransformFuture<I, O> output = new AsyncTransformFuture<>(input, function);
    input.addListener(output, rejectionPropagatingExecutor(executor, output));
    return output;
  }

  static <I extends @Nullable Object, O extends @Nullable Object> ListenableFuture<O> create(

    this.exec = Executors.newCachedThreadPool();
    this.future = checkNotNull(future);
    this.latch = new CountDownLatch(1);
  }

  public void setUp() {
    future.addListener(
        new Runnable() {
          @Override
          public void run() {
            latch.countDown();
          }
        },
        exec);

    assertEquals(1, latch.getCount());

      // Register a listener on each Future in the list to update the state of this future.
      // Note that if all the futures on the list are done prior to completing this loop, the last
      // call to addListener() will callback to setOneValue(), transitively call our cleanup
      // listener, and set this.futures to null.
      // This is not actually a problem, since the foreach only needs this.futures to be non-null

   * service changes state. The listener will not have previous state changes replayed, so it is
   * suggested that listeners are added before the service starts.
   *
   * <p>{@code addListener} guarantees execution ordering across calls to a given listener but not
   * across calls to multiple listeners. Specifically, a given listener will have its callbacks

  // operation in the constructor.
  //
  // 1. In the listener that performs the callback. In this case it is fine since inputFuture is
  //    assigned prior to calling addListener, and addListener happens-before any invocation of the
  //    listener. Notably, this means that 'volatile' is unnecessary to make 'inputFuture' visible
  //    to the listener.
  //

    // taskFuture guarantees completion if the callable is invoked, and adding to outputFuture
    // propagates cancellation if the callable has not yet been invoked.
    outputFuture.addListener(listener, directExecutor());
    taskFuture.addListener(listener, directExecutor());

    return outputFuture;
  }

  enum RunningState {
    NOT_RUN,
    CANCELLED,
    STARTED,
  }

  /**

              }
              return 25;
            }
          });

  @Override
  protected void setUp() throws Exception {
    super.setUp();

    exec = Executors.newCachedThreadPool();

    task.addListener(
        new Runnable() {
          @Override
          public void run() {
            listenerLatch.countDown();
          }
        },
        directExecutor());
  }

  @Override

          }

          @Override
          public String get(long time, TimeUnit unit) {
            return "foo"; // BAD!!
          }

          @Override
          public void addListener(Runnable runnable, Executor executor) {
            executor.execute(runnable);
          }
        };
    Future<?> future = newFutureInstance();
    future
        .getClass()
        .getMethod(