*     queryFuture.transformAsync((closer, result) -> result.getRowsClosingFuture(), executor);
   *
   * // Result.writeRowsToOutputStreamFuture() returns a ListenableFuture that resolves to the
   * // number of written rows. openOutputFile() returns a FileOutputStream (which implements
   * // Closeable).
   * ClosingFuture<Integer> rowsFuture2 =
   *     queryFuture.transformAsync(
   *         (closer, result) -> {

   *     queryFuture.transformAsync((closer, result) -> result.getRowsClosingFuture(), executor);
   *
   * // Result.writeRowsToOutputStreamFuture() returns a ListenableFuture that resolves to the
   * // number of written rows. openOutputFile() returns a FileOutputStream (which implements
   * // Closeable).
   * ClosingFuture<Integer> rowsFuture2 =
   *     queryFuture.transformAsync(
   *         (closer, result) -> {

    assertClosed(closeable1, closeable2);
  }

  public void testTransformAsync() throws Exception {
    ClosingFuture<String> closingFuture =
        ClosingFuture.from(immediateFuture("value"))
            .transformAsync(
                new AsyncClosingFunction<String, TestCloseable>() {
                  @Override
                  public ClosingFuture<TestCloseable> apply(DeferredCloser closer, String v)

   *     input's failure (if not)
   */
  public final <T extends @Nullable Object> FluentFuture<T> transformAsync(
      AsyncFunction<? super V, T> function, Executor executor) {
    return (FluentFuture<T>) Futures.transformAsync(this, function, executor);
  }

  /**
   * Returns a new {@code Future} whose result is derived from the result of this {@code Future}. If

    assertThat(f.get()).isEqualTo(2);
  }

  public void testTransformAsync() throws Exception {
    FluentFuture<Integer> f =
        FluentFuture.from(immediateFuture(1))
            .transformAsync(
                new AsyncFunction<Integer, Integer>() {
                  @Override
                  public ListenableFuture<Integer> apply(Integer input) {
                    return immediateFuture(input + 1);

   * Example usage:
   *
   * {@snippet :
   * ListenableFuture<RowKey> rowKeyFuture = indexService.lookUp(query);
   * ListenableFuture<QueryResult> queryFuture =
   *     transformAsync(rowKeyFuture, dataService::readFuture, executor);
   * }
   *
   * <p>When selecting an executor, note that {@code directExecutor} is dangerous in some cases. See