SpringBoot实现扫码登录的示例代码

//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();

     }

}

< div class = "qrCodeImg-box" id = "qrImgDiv" ></ div >

$(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

        }

    }

}

< dependency >

     < groupId >org.springframework.boot</ groupId >

     < artifactId >spring-boot-starter-websocket</ artifactId >

</ dependency >

/**  * WebSocket的支持  * @return  */

@Bean

public ServerEndpointExporter serverEndpointExporter() {

     return new ServerEndpointExporter();

}

package com.stylefeng.guns.rest.modular.inve.websocket;

/**  * Created by jiangjiacheng on 2019/6/4.  */

import java.io.IOException;

import java.util.concurrent.CopyOnWriteArraySet;

import javax.websocket.OnClose;

import javax.websocket.OnError;

import javax.websocket.OnMessage;

import javax.websocket.OnOpen;

import javax.websocket.Session;

import javax.websocket.server.PathParam;

import javax.websocket.server.ServerEndpoint;

import org.springframework.stereotype.Component;

import cn.hutool.log.Log;

import cn.hutool.log.LogFactory;

@ServerEndpoint ( "/websocket/{sid}" )

@Component

public class WebSocketServer {

     static Log log=LogFactory.get(WebSocketServer. class );

     //静态变量，用来记录当前在线连接数。应该把它设计成线程安全的。

     private static int onlineCount = 0 ;

     //concurrent包的线程安全Set，用来存放每个客户端对应的MyWebSocket对象。

     private static CopyOnWriteArraySet<WebSocketServer> webSocketSet = new CopyOnWriteArraySet<WebSocketServer>();

     //与某个客户端的连接会话，需要通过它来给客户端发送数据

     private Session session;

     //接收sid

     private String sid= "" ;

     /**      * 连接建立成功调用的方法*/

     @OnOpen

     public void onOpen(Session session, @PathParam ( "sid" ) String sid) {

         this .session = session;

         webSocketSet.add( this );     //加入set中

         addOnlineCount();           //在线数加1

         log.info( "有新窗口开始监听:" +sid+ ",当前在线人数为" + getOnlineCount());

         this .sid=sid;

         /*try {             sendMessage("连接成功");         } catch (IOException e) {             log.error("websocket IO异常");         }*/

     }

     /**      * 连接关闭调用的方法      */

     @OnClose

     public void onClose() {

         webSocketSet.remove( this );  //从set中删除

         subOnlineCount();           //在线数减1

         log.info( "有一连接关闭！当前在线人数为" + getOnlineCount());

     }

     /**      * 收到客户端消息后调用的方法      *      * @param message 客户端发送过来的消息*/

     @OnMessage

     public void onMessage(String message, Session session) {

         log.info( "收到来自窗口" +sid+ "的信息:" +message);

         //群发消息

         for (WebSocketServer item : webSocketSet) {

             try {

                 item.sendMessage(message);

             } catch (IOException e) {

                 e.printStackTrace();

             }

         }

     }

     /**      *      * @param session      * @param error      */

     @OnError

     public void onError(Session session, Throwable error) {

         log.error( "发生错误" );

         error.printStackTrace();

     }

     /**      * 实现服务器主动推送      */

     public void sendMessage(String message) throws IOException {

         this .session.getBasicRemote().sendText(message);

     }

     /**      * 群发自定义消息      * */

     public static void sendInfo(String message, @PathParam ( "sid" ) String sid) throws IOException {

         log.info( "推送消息到窗口" +sid+ "，推送内容:" +message);

         for (WebSocketServer item : webSocketSet) {

             try {

                 //这里可以设定只推送给这个sid的，为null则全部推送

                 if (sid == null ) {

                     item.sendMessage(message);

                 } else if (item.sid.equals(sid)){

                     item.sendMessage(message);

                 }

             } catch (IOException e) {

                 continue ;

             }

         }

     }

     public static synchronized int getOnlineCount() {

         return onlineCount;

     }

     public static synchronized void addOnlineCount() {

         WebSocketServer.onlineCount++;

     }

     public static synchronized void subOnlineCount() {

         WebSocketServer.onlineCount--;

     }

}

/**  * 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！" );

     }

}

//这句话比较关键

WebSocketServer.sendInfo(jsonObject.toJSONString(),token);