springMVC返回复杂的json格式数据方法

{
  "total":2,
  "list":[
    {
      "person":{"name":"eakom0","key":0},
      "msg":{"cod":0,"name":"eakom0"}
    },
    {
      "person":{"name":"eakom1","key":1},
      "msg":{"cod":1,"name":"eakom1"}
    }
  ],
  "attachment":{"name":"附件","version":1}
}

@RequestMapping("returnJson")
  public void returnJson (HttpServletRequest request, HttpServletResponse response){
      JSONObject json = new JSONObject(); 
      json.element("total", 2);
      List<Map<String,JSONObject>> list=new ArrayList<Map<String,JSONObject>>();
      for(int i=0;i<2;i++){
        JSONObject person=new JSONObject();
        person.element("name", "eakom"+i);
        person.element("key", i);
        JSONObject msg=new JSONObject();
        msg.element("name", "eakom"+i);
        msg.element("cod", i);
        Map<String,JSONObject> map=new HashMap<String,JSONObject>();
        map.put("person", person);
        map.put("msg", msg);
        list.add(map);
      }
      json.element("list", list);
      JSONObject attachment=new JSONObject();
      attachment.element("name", "附件");
      attachment.element("version", 1);
      json.element("attachment", attachment);
      responseDatagrid(response, json);
  }
  public void responseDatagrid(HttpServletResponse response, JSONObject jObject) {
    response.setContentType("application/json");
    response.setHeader("Cache-Control", "no-store");
    try {
      PrintWriter pw=response.getWriter();
      pw.write(jObject.toString());
      pw.flush();
    } catch (IOException e) {
      e.printStackTrace();
    }
  }