code: public static String doPost(final String action, final Map<String, String> parameters,
      final int retryTimes) {
  
      try {
        return doPostByLoop(action, parameters, retryTimes);
      } catch (HttpException e) {
        throw new HttpException(format(
          "Failed to download content for action url: '%s' with parameters. Tried '%s' times",
          action, parameters, Math.max(retryTimes + 1, 1)));
      }
    }
docs: access given action with given parameters by post, if get exception, will
  retry by given retryTimes.
  
  @param action action url to access
  @param parameters parameters to post
  @param retryTimes retry times when get exception.
  @return response content of target action url.