*/
  @CheckForNull @LazyInit ListenableFuture<? extends I> inputFuture;
  @CheckForNull @LazyInit F function;

  AbstractTransformFuture(ListenableFuture<? extends I> inputFuture, F function) {
    this.inputFuture = checkNotNull(inputFuture);
    this.function = checkNotNull(function);
  }

  @Override