super(inputFuture, function);
    }

    @Override
    ListenableFuture<? extends O> doTransform(
        AsyncFunction<? super I, ? extends O> function, @ParametricNullness I input)
        throws Exception {
      ListenableFuture<? extends O> outputFuture = function.apply(input);
      checkNotNull(
          outputFuture,

  }

  /**
   * An {@link AbstractCatchingFuture} that delegates to an {@link AsyncFunction} and {@link
   * #setFuture(ListenableFuture)}.
   */
  private static final class AsyncCatchingFuture<V extends @Nullable Object, X extends Throwable>
      extends AbstractCatchingFuture<
          V, X, AsyncFunction<? super X, ? extends V>, ListenableFuture<? extends V>> {
    AsyncCatchingFuture(

   * Returns a {@code Future} whose result is taken from the given primary {@code input} or, if the
   * primary input fails with the given {@code exceptionType}, from the result provided by the
   * {@code fallback}. {@link AsyncFunction#apply} is not invoked until the primary input has
   * failed, so if the primary input succeeds, it is never invoked. If, during the invocation of

   * Returns a {@code Future} whose result is taken from the given primary {@code input} or, if the
   * primary input fails with the given {@code exceptionType}, from the result provided by the
   * {@code fallback}. {@link AsyncFunction#apply} is not invoked until the primary input has
   * failed, so if the primary input succeeds, it is never invoked. If, during the invocation of