code: public static <T> ValueSourceFuture<T> createValueSourceFuture(ApiFuture<T> apiFuture) {
          if (apiFuture instanceof ValueSourceFutureBackedApiFuture) {
              return ((ValueSourceFutureBackedApiFuture<T>) apiFuture).getWrappedFuture();
          } else {
              return new ApiFutureBackedValueSourceFuture<>(apiFuture);
          }
      }
docs: *************************************** Converting from ApiFuture ******************************************