@RequestMapping(value = "adduser.htm", method = RequestMethod.POST)
 public String registerUser(@ModelAttribute("RegisterUser") User user, Model model) {
   regdao.addUser(
       regdao.maxKey("User", "user_id") + 1,
       user.getUsername(),
       user.getFirst_name(),
       user.getLast_name(),
       user.getProfile_pic(),
       user.getEmail(),
       user.getPassword());
   return "Register";
 }
 @RequestMapping(value = "/add", method = RequestMethod.POST)
 public JSONObject add(@ModelAttribute("user") User user) {
   JSONObject json = new JSONObject();
   try {
     user.setPassword(PwdUtil.md5(user.getUsername() + user.getPassword()));
     userBiz.save(user);
     json.put("err", 0);
     json.put("msg", "保存成功,成功后的ID为:" + user.getId());
   } catch (Exception e) {
     json.put("err", 1);
     json.put("msg", "保存失败!");
     Constans.LOG.error(e);
   }
   return json;
 }