ajax跨域

/**
     * 需求:根据token查询redis服务器用户身份信息
     * 请求:http://localhost:8088/user/token/" + _ticket??callback=jQuery2795009&_=1506226664795
     * 参数:String token
     * 返回值:E3mallResult
     * {
        status: 200
        msg: "OK"
        data: "{"id":1,"username":"zhangzhijun","phone":"15800807944",
        "email":"420840806@qq.com","created":1414119176000,"updated":1414119179000}"
      }

     */
    @RequestMapping("/user/token/{token}")
    @ResponseBody
    public Object findRedisWithToken(@PathVariable String token,String callback){
        //调用远程service对象方法
        E3mallResult result = userService.findRedisWithToken(token);
        //判断是否跨域请求
        if(StringUtils.isBlank(callback)){            
            //返回
            return result;
        }
        //否则就是跨域请求
        //return "callback("++")"
        //使用Jackson自动支持ajax跨域数据转换
        MappingJacksonValue jacksonValue = new MappingJacksonValue(result);
        //设置回调函数
        jacksonValue.setJsonpFunction(callback);
        
        return jacksonValue;
    }