code: public static void checkSuccess(Future<?> future, String errorMessage)
      {
          requireNonNull(future, "future is null");
          requireNonNull(errorMessage, "errorMessage is null");
          checkArgument(future.isDone(), "future not done yet");
          try {
              getFutureValue(future);
          }
          catch (RuntimeException e) {
              throw new IllegalArgumentException(errorMessage, e);
          }
      }
docs: Checks that the completed future completed successfully.