@RequestMapping(value = "", method = RequestMethod.POST)    public Result get(@RequestBody User user,                      @RequestParam("username") String hehe) throws Exception {}如何能夠接受user對象的同時(shí)，同時(shí)接受username？假設(shè)User對象為public class User  {    private String id;    private String username;    private String email;    private String phone;}