code: public static String getBody(ServletRequest request) {
  		try {
  			return IoUtil.read(request.getReader());
  		} catch (IOException e) {
  			throw new IORuntimeException(e);
  		}
  	}
docs: 获取请求体<br>
  调用该方法后，getParam方法将失效
  
  @param request {@link ServletRequest}
  @return 获得请求体
  @since 4.0.2