code: public <T extends MwsObject> Future<T> callAsync(final MwsRequestType type,
              final MwsObject requestData) {
          return getExecutorService().submit(new Callable<T>() {
              @Override
              public T call() {
                  return MwsConnection.this.call(type, requestData);
              }
          });
      }
docs: Call a request async, return a future on the response data.
  
  @param requestData
  
  @return A future on the response data.