关于HttpServletRequest获取POST请求Body参数的3种方式

     /**
     * If the parameter data was sent in the request body, such as occurs
     * with an HTTP POST request, then reading the body directly via
     * @see javax.servlet.ServletRequest#getInputStream or
     * @see javax.servlet.ServletRequest#getReader
     * @param request HttpServletRequest
     * @return String
     */
    public static String getPostData(HttpServletRequest request) {
        StringBuilder data = new StringBuilder();
        String line;
        BufferedReader reader;
        try {
            reader = request.getReader();
            while (null != (line = reader.readLine())) {
                data.append(line);
            }
        } catch (IOException e) {
            return null;
        }
        return data.toString();
    }

    @RequestMapping(value = "hello", method = {RequestMethod.POST})
    @ResponseBody
    public String batchDisabledUsers(@RequestBody xxxDTO  xx) {
 
    }

@RequestMapping(value = "/testurl", method = RequestMethod.POST)
@ResponseBody
public StringTestUrl(@RequestParam("username")String username,         
                 @RequestParam("pwd")String pwd)  {
  String txt = username + pwd;
  return txt;
}