code: @Override
      public void onSuccess(Consumer<T> consumer) {
          Validator.requireNonNull(consumer, "Null is not a valid consumer");
          // register a complete handler and ignore any Failure responses
          onComplete(result -> {
              // should it be a Failure the forEach will do nothing
              result.forEach(consumer);
          });
      }
docs: /*
  (non-Javadoc)
  
  @see javascalautils.concurrent.Future#onSuccess(java.util.function.Consumer)