Spring Boot + Web Socket 实现扫码登录，这种方式太香了！！

//获取登录二维码、放入Token
@RequestMapping(value = "/getLoginQr" ,method = RequestMethod.GET)
public void createCodeImg(HttpServletRequest request, HttpServletResponse response){
    response.setHeader("Pragma", "No-cache");
    response.setHeader("Cache-Control", "no-cache");
    response.setDateHeader("Expires", 0);
    response.setContentType("image/jpeg");
    try {
        //这里没啥操作 就是生成一个UUID插入 数据库的表里
        String uuid = userService.createQrImg();
        response.setHeader("uuid", uuid);
        // 这里是开源工具类 hutool里的QrCodeUtil 
        // 网址：http://hutool.mydoc.io/
        QrCodeUtil.generate(uuid, 300, 300, "jpg",response.getOutputStream());
    } catch (Exception e) {
        e.printStackTrace();
    }
}

$(document).ready(function(){
    initQrImg();
});
 function initQrImg(){
    $("#qrImgDiv").empty();
    var xmlhttp;
    xmlhttp=new XMLHttpRequest();
    xmlhttp.open("GET",getQrPath,true);
    xmlhttp.responseType = "blob";
    xmlhttp.onload = function(){
        console.log(this);
        uuid = this.getResponseHeader("uuid");
        if (this.status == 200) {
            var blob = this.response;
            var img = document.createElement("img");
            img.className = 'qrCodeBox-img';
            img.onload = function(e) {
                window.URL.revokeObjectURL(img.src);
            };
            img.src = window.URL.createObjectURL(blob);
            document.getElementById("qrImgDiv").appendChild(img);
            initWebSocket();
        }
    }
    xmlhttp.send();
}
var path = "://localhost:8085";
var getQrPath =  "http" + path + "/user/getLoginQr";
var wsPath =     "ws" + path + "/websocket/";
function initWebSocket(){
   if(typeof(WebSocket) == "undefined") {
       console.log("您的浏览器不支持WebSocket");
   }else{
       console.log("您的浏览器支持WebSocket");
       //实现化WebSocket对象，指定要连接的服务器地址与端口  建立连接
       //等同于socket = new WebSocket("ws://localhost:8083/checkcentersys/websocket/20");
       var wsPathStr = wsPath+uuid;
       socket = new WebSocket(wsPathStr);
       //打开事件
       socket.onopen = function() {
           console.log("Socket 已打开");
           //socket.send("这是来自客户端的消息" + location.href + new Date());
       };
       //获得消息事件
       socket.onmessage = function(msg) {
           console.log(msg.data);
           var data = JSON.parse(msg.data);
           if(data.code == 200){
               alert("登录成功！");
               //这里存放自己业务需要的数据。怎么放自己看
               window.sessionStorage.uuid = uuid;
               window.sessionStorage.userId = data.userId;
               window.sessionStorage.projId = data.projId;
               window.location.href = "pages/upload.html"
           }else{
               //如果过期了，关闭连接、重置连接、刷新二维码
               socket.close();
               initQrImg();
           }
           //发现消息进入    开始处理前端触发逻辑
       };
       //关闭事件
       socket.onclose = function() {
           console.log("Socket已关闭");
       };
       //发生了错误事件
       socket.onerror = function() {
           alert("Socket发生了错误");
           //此时可以尝试刷新页面
       }
   }
}

/**
 * 确认身份接口：确定身份以及判断是否二维码过期等
 * @param token
 * @param userId
 * @return
 */
@RequestMapping(value = "/bindUserIdAndToken" ,method = RequestMethod.GET)
@ResponseBody
public Object bindUserIdAndToken(@RequestParam("token") String token ,
                                 @RequestParam("userId") Integer userId,
                                 @RequestParam(required = false,value = "projId") Integer projId){
    try {
        return new SuccessTip(userService.bindUserIdAndToken(userId,token,projId));
    } catch (Exception e) {
        e.printStackTrace();
        return new ErrorTip(500,e.getMessage());
    }
}

@Override
public String bindUserIdAndToken(Integer userId, String token,Integer projId) throws Exception {
    QrLoginToken qrLoginToken = new QrLoginToken();
    qrLoginToken.setToken(token);
    qrLoginToken = qrLoginTokenMapper.selectOne(qrLoginToken);
    if(null == qrLoginToken){
        throw  new Exception("错误的请求！");
    }
    Date createDate = new Date(qrLoginToken.getCreateTime().getTime() + (1000 * 60 * Constant.LOGIN_VALIDATION_TIME));
    Date nowDate = new Date();
    if(nowDate.getTime() > createDate.getTime()){//当前时间大于校验时间
        JSONObject jsonObject = new JSONObject();
        jsonObject.put("code",500);
        jsonObject.put("msg","二维码失效！");
        WebSocketServer.sendInfo(jsonObject.toJSONString(),token);
        throw  new Exception("二维码失效！");
    }
    qrLoginToken.setLoginTime(new Date());
    qrLoginToken.setUserId(userId);
    int i = qrLoginTokenMapper.updateById(qrLoginToken);
    JSONObject jsonObject = new JSONObject();
    jsonObject.put("code",200);
    jsonObject.put("msg","ok");
    jsonObject.put("userId",userId);
    if(ToolUtil.isNotEmpty(projId)){
        jsonObject.put("projId",projId);
    }
    WebSocketServer.sendInfo(jsonObject.toJSONString(),token);
    if(i > 0 ){
        return null;
    }else{
        throw  new Exception("服务器异常！");
    }
}