项目结构
导入依赖
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<spring-boot.version>2.3.7.RELEASE</spring-boot.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.72</version>
</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>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
<!--websocket-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-websocket</artifactId>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
</dependency>
<!--工具包-->
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.5</version>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-dependencies</artifactId>
<version>${spring-boot.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
<encoding>UTF-8</encoding>
</configuration>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.7.RELEASE</version>
<configuration>
<mainClass>com.example.demo.DemoApplication</mainClass>
</configuration>
<executions>
<execution>
<id>repackage</id>
<goals>
<goal>repackage</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
application.yml配置文件
server:
port: 8080
spring:
http:
encoding:UTF-8
freemarker:
request-context-attribute: request
#prefix: /templates/
suffix: .html
content-type: text/html
enabled: true
cache: false
charset: UTF-8
allow-request-override: false
expose-request-attributes: true
expose-session-attributes: true
expose-spring-macro-helpers: true
WebSocketConfig: 用于开启WebSocket支持
package com.example.demo.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.server.standard.ServerEndpointExporter;
/**
* @author lyd
* @Description: 开启WebSocket支持
* @date 15:43
*/
@Configuration
public class WebSocketConfig {
@Bean
public ServerEndpointExporter serverEndpointExporter(){
return new ServerEndpointExporter();
}
}
WebSocketServer: 核心类,用于开启、关闭连接,以及接收消息等
比较重要的注解 @ServerEndpoint("")
、@OnOpen
、@onClose
、@onMessage
package com.example.demo.server;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.springframework.stereotype.Component;
import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.concurrent.ConcurrentHashMap;
/**
* @author lyd
* @Description: 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,
* 所以可以直接在前端调用@ServerEndpoint("")中的路径,相当于掉接口了
* @date 15:48
*/
@Slf4j
@Component
@ServerEndpoint("/imserver/{userId}")
public class WebSocketServer {
/**
* 静态变量,用来记录当前在线连接数
*/
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WebSocket对象
*/
private static ConcurrentHashMap<String, WebSocketServer> webSocketMap = new ConcurrentHashMap<>();
/**
* 连接会话,给客户端发送数据
*/
private Session session;
/**
* 接收userId
*/
private String userId = "";
/**
* 连接建立成功调用的方法
*/
@OnOpen
public void onOpen(Session session, @PathParam("userId") String userId) {
this.session = session;
this.userId = userId;
if (webSocketMap.containsKey(userId)) {
webSocketMap.remove(userId);
webSocketMap.put(userId, this);
addOnlineCount();
} else {
webSocketMap.put(userId, this);
addOnlineCount();
}
log.info("用户" + userId + "连接,当前在线人数为:" + getOnlineCount());
try {
sendMessage("连接成功");
} catch (IOException e) {
log.error("用户:" + userId + ",网络异常,哈哈哈");
e.printStackTrace();
}
}
/**
* 连接关闭调用的方法
*/
@OnClose
public void onClose() {
if (webSocketMap.containsKey(userId)) {
webSocketMap.remove(userId);
subOnlineCount();
}
log.info("用户:" + userId + "退出成功,当前在线人数为:" + getOnlineCount());
}
/**
* 收到客户端消息后调用的方法
*/
@OnMessage
public void onMessage(String message, Session session) {
log.info("用户消息:" + userId + ",报文:" + message);
//可以群发消息
//消息保存到数据库、redis
if (StringUtils.isNotBlank(message)) {
try {
// 解析报文
JSONObject jsonObject = JSON.parseObject(message);
// 追加发送人(防止串改)
jsonObject.put("fromUserId", this.userId);
String toUserId = jsonObject.getString("toUserId");
if (StringUtils.isNotBlank(toUserId) && webSocketMap.containsKey(toUserId)) {
webSocketMap.get(toUserId).sendMessage(jsonObject.toJSONString());
}else {
log.error("请求的userId:"+toUserId+"不在该服务器上");
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* 实现服务器消息主动推送
*
* @param message
* @throws IOException
*/
public void sendMessage(String message) throws IOException {
this.session.getBasicRemote().sendText(message);
}
/**
* 发送自定义消息
*/
public static void sendInfo(String message, @PathParam("userId") String userId) throws IOException {
log.info("发送消息到:" + userId + ",报文:" + message);
if (StringUtils.isNotBlank(userId) && webSocketMap.containsKey(userId)) {
webSocketMap.get(userId).sendMessage(message);
} else {
log.error("用户" + userId + ",不在线!");
}
}
/**
* 获得当前连接数
*
* @return
*/
public static synchronized int getOnlineCount() {
return onlineCount;
}
/**
* 在线连接数加1
*/
public static synchronized void addOnlineCount() {
WebSocketServer.onlineCount++;
}
/**
* 在线连接数减1
*/
public static synchronized void subOnlineCount() {
WebSocketServer.onlineCount--;
}
/**
* @param session
* @param error
*/
@OnError
public void onError(Session session, Throwable error) {
log.error("用户错误:" + this.userId + ",原因:" + error.getMessage());
error.printStackTrace();
}
}
消息推送
写个controller接口调用WebSocketServer.sendInfo()
package com.example.demo.controller;
import com.example.demo.server.WebSocketServer;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.servlet.ModelAndView;
import javax.websocket.server.PathParam;
import java.io.IOException;
/**
* @author lyd
* @Description:
* @date 16:31
*/
@RestController
public class DemoController {
/**
* 接口测试
* @return
*/
@RequestMapping("index")
public ResponseEntity index(){
return ResponseEntity.ok("请求成功");
}
/**
* 页面跳转
* @return
*/
@RequestMapping("page")
public ModelAndView page(){
return new ModelAndView("testPage.html");
}
/**
* 消息推送
* @param message
* @param toUserId
* @return
* @throws IOException
*/
@RequestMapping("pushToWeb")
public ResponseEntity<String> pushToWeb(String message, @PathParam("toUserId") String toUserId) throws IOException {
WebSocketServer.sendInfo(message,toUserId);
return ResponseEntity.ok("MSG SEND SUCCESS");
}
}
前端页面代码
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>websocket通讯</title>
</head>
<script src="https://cdn.bootcss.com/jquery/3.3.1/jquery.js"></script>
<script>
var socket;
function openSocket() {
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:8888/xxxx/im/25");
//var socketUrl="${request.contextPath}/im/"+$("#userId").val();
var socketUrl = "http://localhost:8080/imserver/" + $("#userId").val();
socketUrl = socketUrl.replace("https", "ws").replace("http", "ws");
console.log(socketUrl);
if (socket != null) {
socket.close();
socket = null;
}
socket = new WebSocket(socketUrl);
//打开事件
socket.onopen = function () {
console.log("websocket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);
//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("websocket已关闭");
};
//发生了错误事件
socket.onerror = function () {
console.log("websocket发生了错误");
}
}
}
function sendMessage() {
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");
console.log(\'{"toUserId":"\' + $("#toUserId").val() + \'","contentText":"\' + $("#contentText").val() + \'"}\');
socket.send(\'{"toUserId":"\' + $("#toUserId").val() + \'","contentText":"\' + $("#contentText").val() + \'"}\');
}
}
</script>
<body>
<p>【userId】:
<div><input id="userId" name="userId" type="text" value="10"></div>
<p>【toUserId】:
<div><input id="toUserId" name="toUserId" type="text" value="20"></div>
<p>【发送内容】:
<div><input id="contentText" name="contentText" type="text" value="hello websocket"></div>
<p>【操作】:
<div><a onclick="openSocket()">开启socket</a></div>
<p>【操作】:
<div><a onclick="sendMessage()">发送消息</a></div>
</body>
</html>
建立连接
发送消息
项目源码
https://github.com/Wranglery/test-websocket
感谢大佬的代码参考:https://blog.csdn.net/moshowgame/article/details/80275084