jquery 对 java后台换回的 json解析失败

Question

ff上报错是：SyntaxError: JSON.parse: unexpected keyword at line 1 column 1 of the JSON data

前端代码

 ChatMassage cm = ChatMassage.instance();
        String mas = cm.getMassage(num);
        int massageNumber = ChatMassage.mass_num;
        System.out.println("mnumber:"+massageNumber);
        session.setAttribute("massageNumber", massageNumber);
        JSONObject json = new JSONObject();
        json.put("massage", mas);
        json.put("massageNumber", massageNumber);
        System.out.println(json);

        return json;

前端问题

function loadMassage(){
    $.ajax({
        data: "num=" + massageNumber,
        url: "loadData.do",
        Success: $(function(msg){

            var res =$.parseJSON(msg);
            alert(parseInt(res.massageNumber));
            massageNumber=parseInt(res.massageNumber);
            massages+=res.massgae;
            document.body.innerHTML=massages;
        })
    });

json生成部分

 } else {
            cm.addUser(name);
            HttpSession session = request.getSession();
            session.setAttribute("username", name);
            SimpleDateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
            String data = dateFormat.format(new Date());
            cm.setMassage("<br><font color=\'red\'> welcom "+name+" join in chatting" + " at "+data+"</font><br>");
        }

 request header:
 Host: localhost:8080
User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:57.0) Gecko/20100101 Firefox/57.0
Accept: */*
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Referer: http://localhost:8080/spring/chat
X-Requested-With: XMLHttpRequest
Cookie: JSESSIONID=26FBFB1DFC7729A3E1A423AECA8B2995
DNT: 1
Connection: keep-alive

Response Header:
Server: Apache-Coyote/1.1
Content-Type: : application/json
Content-Length: 108
Date: Mon, 25 Dec 2017 16:33:01 GMT

在返回时已设置编码

 Object result = action.execute(request, response);
        if(result instanceof String)
        {
            request.getRequestDispatcher(result.toString()).forward(request, response);
        } else if (result instanceof JSONObject) {
            response.setHeader("Content-Type:", "application/json");
            response.setCharacterEncoding("utf-8");
            response.getWriter().print((JSONObject)result);
        }

因为是 Linux 系统，所以一般情况下不会出现编码问题。并且我也将中文全部替换为英文。

之前在没开 debug 时，解析全部为 undefinded

Answer 1

解析全部为 undefinded