Java接收回调

public void toCallback(HttpServletRequest request){
        String responseMsg;
        try {
            StringBuffer sb = new StringBuffer(2000);
            InputStream is = request.getInputStream();

            BufferedReader br = new BufferedReader(new InputStreamReader(is, "UTF-8"));
            // 读取HTTP请求内容
            String buffer = null;
            while ((buffer = br.readLine()) != null) {
                // 在页面中显示读取到的请求参数
                sb.append(buffer);
            }
            responseMsg = sb.toString().trim();
            log.info("服务器响应报文:【" + responseMsg+"】");
        }catch (Exception e){

            return ;
        }
        }