Spring Mvc:使用ModelAndView返回json

package cn.edu.tju.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.view.json.MappingJackson2JsonView;

@Controller
public class JsonController {

    @RequestMapping("/json")
    public ModelAndView modelAndView(){
        ModelAndView modelAndView = new ModelAndView(new MappingJackson2JsonView());
        modelAndView.addObject("code", 200);
        modelAndView.addObject("message", "my message");
        return modelAndView;
    }


}