websocket是h5后的技术，主要实现是一个长连接跟tomcat的comet技术差不多，但websocket是基于web协议的，有更广泛的支持。当然，在处理高并发的情况下，可以结合tomcat的asyncContext来实现长处理的异步返回等操作。
1.引入依赖类
<dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.16.18</version> </dependency> <!-- websocket dependency --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-websocket</artifactId> </dependency>
这里主要是引入websocket的依赖类
2.springboot配置websocket的入口bean
在springboot的配置类下，引入以下的配置bean
@Bean public ServerEndpointExporter serverEndpointExporter() { return new ServerEndpointExporter(); }
3.实现websocket的后端处理逻辑
package com.ouyang.server; import lombok.extern.slf4j.Slf4j; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.stereotype.Component; import javax.websocket.*; import javax.websocket.server.ServerEndpoint; import java.io.IOException; import java.util.concurrent.ConcurrentHashMap; import java.util.concurrent.CopyOnWriteArraySet; /** * Created by Administrator on 2018/3/25. */ //@Slf4j @ServerEndpoint(value = "/websocket") @Component public class WebSocketServer { Logger log = LoggerFactory.getLogger(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>(); // 备用的同步hashmap //private static ConcurrentHashMap<Session,WebSocketServer> webSocketServerConcurrentHashMap = new ConcurrentHashMap(); //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; /** * 连接建立成功调用的方法*/ @OnOpen public void onOpen(Session session) { this.session = session; webSocketSet.add(this); //加入set中 addOnlineCount(); //在线数加1 log.info("有新连接加入！当前在线人数为" + getOnlineCount()); try { sendMessage("连接成功"); } catch (IOException e) { log.error("websocket IO异常"); } } // //连接打开时执行 // @OnOpen // public void onOpen(@PathParam("user") String user, Session session) { // currentUser = user; // System.out.println("Connected ... " + session.getId()); // } /** * 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) throws IOException { log.info("来自客户端的消息:" + message); //群发消息 for (WebSocketServer item : webSocketSet) { try { item.sendMessage("response message:"+message); } catch (IOException e) { e.printStackTrace(); } } //单发的信息 sendMessage("currentWebsocket is ok!!! "); } /** * * @param session * @param error */ @OnError public void onError(Session session, Throwable error) { log.error("发生错误"); error.printStackTrace(); } /** * * @param message * @throws IOException */ 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) throws IOException { //log.info(message); for (WebSocketServer item : webSocketSet) { try { 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--; } }
至此，我们关于后台的websocket的主要实现类都实现了，接下来我们可以弄一个，测试的接口，用于给所有的websocket推送信息，如下：
@RequestMapping(value="/publicSend",method= RequestMethod.GET) @ResponseBody public String pushVideoListToWeb2(String id) { try { WebSocketServer.sendInfo("有新客户呼入,sltAccountId:"+id); for(int i= 0;i<20;i++){ WebSocketServer.sendInfo("有新客户呼入,testing:"+String.valueOf(i)); } }catch (IOException e) { } return "success!"; }
4.前端测试页面的实现
<!DOCTYPE html> <html lang="en" xmlns:th="http://www.springframework.org/schema/jdbc"> <head> <meta charset="UTF-8"> <title>Title</title> <script src="/static/jquery.js"></script> <script src="/static/stomp.min.js"></script> <script src="/static/sockjs.min.js"></script> <script> //socket = new WebSocket("ws://localhost:8081/begenstom/websocket"); var socket; 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 //socket = new WebSocket("ws://localhost:9094/starManager/websocket/张三"); socket = new WebSocket("ws://localhost:8081/websocket"); //打开事件 socket.onopen = function () { console.log("Socket 已打开"); for (var i=0;i<20;i++) { socket.send("这是来自客户端的消息1:" + i); } //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); //发现消息进入 调后台获取 document.write(msg.data); }; //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"); } $(window).unload(function () { socket.close(); }); } </script> </head> <body> </body> </html>
这里主要用到3个js，可以去github上去当一个。
参考地址：
* https://blog.csdn.net/zhangdehua678/article/details/78913839
* https://github.com/ayman-elgharabawy/Kafka-SpringBoot-WebSocket
* 整合框架 https://github.com/527515025/springBoot
