1. 项目介绍
- 客户端页面index.html可以输入消息，点击发送，通过ws协议发送到服务器端；
- 服务器端收到客户端消息后，广播给各个客户端；
- 服务器端页面server.html，可以输入消息，点击发送，通过ws双工通信推送给客户端；
- 客户端有显示服务器端广播消息的区域。
2. 项目目录结构
3. 项目代码分析
3.1 pom.xml文件添加必要依赖
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!--WebSocket-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-websocket</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.webjars</groupId>
<artifactId>bootstrap</artifactId>
<version>3.3.7-1</version>
</dependency>
</dependencies>
3.2 .java代码
- 新建WebSocket 的配置类WebSocketConfig.java
package com.springboot.websocket.websocket.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.server.standard.ServerEndpointExporter;
/**
* WebSocket配置类
*
*/
@Configuration
public class WebSocketConfig {
@Bean
public ServerEndpointExporter serverEndpointExporter() {
return new ServerEndpointExporter();
}
}
package com.springboot.websocket.websocket.config;
import org.springframework.stereotype.Component;
import javax.websocket.*;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.concurrent.CopyOnWriteArraySet;
/**
* WebSocket的服务端
* 因为WebSocket是类似客户端服务端的形式(采用ws协议)，
* 那么这里的WebSocketServer其实就相当于一个ws协议的Controller
* 直接@ServerEndpoint(“/websocket”)@Component启用即可，
* 然后在里面实现@OnOpen,@onClose,@onMessage等方法
*/
@ServerEndpoint("/websocket")
@Component
public class WebSocketServer {
//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。可选的
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。必须要有的
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，必须
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
//一旦连接成功后就在控制台打印信息
System.out.println("有新窗口开始监听,当前在线人数为" + getOnlineCount());
try {
//往客户端发送消息
sendMessage("连接成功");
} catch (IOException e) {
System.out.println("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
System.out.println("有连接关闭！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) {
//message 是从客户端发送过来的消息，并在控制台打印
System.out.println("收到客户端的信息:" + 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) {
System.out.println("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) throws IOException {
System.out.println("推送消息内容:" + 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--;
}
}
- WebSocketController.java 控制层代码
package com.springboot.websocket.websocket.controller;
import com.springboot.websocket.websocket.config.WebSocketServer;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import java.io.IOException;
/**
* WebSocketController
*/
@Controller
@RequestMapping("/socket")
public class WebSocketController {
/**
* 输入消息的页面
* @return
*/
@GetMapping("/send")
public String sendMsg(){
return "server";
}
/**
* 推送数据接口
* @Param message
* @return
*/
@RequestMapping("/push")
public String pushMsg(@RequestParam("message")String message) {
try {
WebSocketServer.sendInfo(message);
} catch (IOException e) {
e.printStackTrace();
}
return "server";
}
}
3.3 html页面代码
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>WebSocket</title>
</head>
<body>
<h1>WebScoket练习</h1>
<label>
<input id="msg" type="text" name="message" style="width:215px;" />
<input type="submit" id="btn" />
</label>
<br>
<div>
<ul id="message_show_ul">
</ul>
</div>
<script language="JavaScript">
var send_message = document.getElementById("msg");
var sub_button = document.getElementById("btn");
var show_ul = document.getElementById("message_show_ul");
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建立连接
socket = new WebSocket("ws://localhost:8088/websocket");
//打开事件
socket.onopen = function () {
console.log("Socket已打开");
sub_button.onclick = function () {
console.log(send_message);
//下面这句话是往服务器发送消息
socket.send("这是来自客户端的消息:" + send_message.value);
};
};
//获得消息事件，从服务器获得消息
socket.onmessage = function (msg) {
var li_eme = document.createElement("li");
li_eme.innerHTML = msg.data;
show_ul.appendChild(li_eme);
//控制台打印消息
console.log(msg.data);
//弹出框弹出消息
// alert(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");
}
}
</script>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>WebSocketServer</title>
</head>
<body>
<h1>服务器端</h1>
<form id="login" action="/socket/push" method="get">
<label>
<input id="msg" type="text" name="message" style="width:215px;" />
<input type="submit" id="btn"/>
</label>
<br>
</form>
</body>
</html>
