websocket介绍
1.websocket介绍1.1注解介绍2.demo2.1 后端代码2.2 前端代码2.3 效果附录:socket地址404问题解决1.websocket介绍
WebSocket是一种在单个TCP连接上进行全双工通信的协议。WebSocket通信协议于被IETF定为标准RFC 6455，并由RFC7936补充规范。WebSocket API也被W3C定为标准。
WebSocket使得客户端和服务器之间的数据交换变得更加简单，允许服务端主动向客户端推送数据。在WebSocket API中，浏览器和服务器只需要完成一次握手，两者之间就直接可以创建持久性的连接，并进行双向数据传输。
1.1注解介绍
@ServerEndpoint 注解是一个类层次的注解，它的功能主要是将目前的类定义成一个websocket服务器端。注解的值将被用于监听用户连接的终端访问URL地址。@OnMessage 前端发送消息 进行处理@OnClose 关闭处理@OnOpen 前端打开页面的处理
2.demo
引入依赖:
compile group: 'org.springframework.boot', name: 'spring-boot-starter-websocket', version: '2.5.5'
2.1 后端代码
package com.zqm.utils.socket;/*** @describe: sid 需要提前约定* @author:zqm*/import mons.lang3.StringUtils;import org.ponent;import javax.websocket.OnClose;import javax.websocket.OnMessage;import javax.websocket.OnOpen;import javax.websocket.Session;import javax.websocket.server.PathParam;import javax.websocket.server.ServerEndpoint;import java.io.IOException;import java.util.concurrent.ConcurrentHashMap;@ServerEndpoint("/websocket/{sid}")@Componentpublic class WebSocketTest {private static final ConcurrentHashMap<String, Session> SESSION_MAP = new ConcurrentHashMap();/*** 接受消息* @param sid* @param session* @throws IOException* @throws InterruptedException// @OnMessage// public void onMessage(@PathVariable("sid") String sid, Session session)// throws IOException, InterruptedException {// System.out.println();// }*//*** 接受消息** @param message 客户端发送的消息* @param session* @throws IOException* @throws InterruptedException*/@OnMessagepublic void onMessage(String message, Session session) {System.out.println(session.getPathParameters().get("sid"));System.out.println(message);}/*** 登记连接** @param sid* @param session*/@OnOpenpublic void onOpen(@PathParam("sid") String sid, Session session) {if (SESSION_MAP.containsKey(sid)) {return;}SESSION_MAP.put(sid, session);System.out.println("Client connected");}/*** 注销连接*/cpublic void onClose() {System.out.println("Connection closed");}public void sendMessage(String sid, String message) throws IOException {if (StringUtils.isNotBlank(sid)) {Session session = SESSION_MAP.get(sid);session.getBasicRemote().sendText(message);}}}package com.zqm.controller;import com.zqm.utils.socket.WebSocketTest;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController;import java.io.IOException;/*** @describe:* @author:zqm*/@RestController@RequestMapping("web-socket")public class WebSocketController {@Autowiredprivate WebSocketTest webSocketTest;@RequestMapping("send")public void sendMessage(String message) throws IOException {webSocketTest.sendMessage("user000",message);}}
2.2 前端代码
<!DOCTYPE html><html><head><meta charset="UTF-8"><title></title></head><body>Websocket Demo <br /><input id="text" type="text" /> <button onclick="send()"> Send </button> <button onclick="closeWebSocket()"> Close </button><div id="message"> </div><script type="text/javascript">//判断当前浏览器是否支持WebSocketif('WebSocket' in window){websocket = new WebSocket("ws://192.168.43.12:8081/zqm/websocket/user");console.log("link success")}else{alert('Not support websocket')}//连接发生错误的回调方法websocket.onerror = function(){setMessageInnerHTML("error");};//连接成功建立的回调方法websocket.onopen = function(event){setMessageInnerHTML("open");}console.log("-----")//接收到消息的回调方法websocket.onmessage = function(event){setMessageInnerHTML(event.data);}//连接关闭的回调方法websocket.onclose = function(){setMessageInnerHTML("close");}//监听窗口关闭事件，当窗口关闭时，主动去关闭websocket连接，防止连接还没断开就关闭窗口，server端会抛异常。window.onbeforeunload = function(){websocket.close();}//将消息显示在网页上function setMessageInnerHTML(innerHTML){document.getElementById('message').innerHTML += innerHTML + '<br/>';}//关闭连接function closeWebSocket(){websocket.close();}//发送消息function send(){var message = document.getElementById('text').value;websocket.send(message);}</script></body></html>
2.3 效果
1.先启动后端服务，打开html，显示连接成功
2.客户端发送消息，后台接受成功
3.后台发送消息，客户端接受成功
附录:socket地址404问题解决
@Configuration@EnableWebSocketpublic class WebSocketConfig {@Beanpublic ServerEndpointExporter serverEndpoint() {return new ServerEndpointExporter();}}或者@Configurationpublic class WebSocketConfig extends ServerEndpointConfig.Configurator{@Beanpublic ServerEndpointExporter serverEndpoint() {return new ServerEndpointExporter();}}
![java socket 全双工客户端_[Java教程]用socket模拟实现全双工通信](https://200zi.50zi.cn/uploadfile/img/15/101/c9199ba0a384830ff52f79ec06922ba9.jpg)
