功能介绍#

客户端给所有在线用户发送消息
客户端给指定在线用户发送消息
服务器给客户端发送消息(轮询方式)

注意：socket只是实现一些简单的功能，具体的还需根据自身情况，代码稍微改造下

项目搭建#

项目结构图#

Spring Boot+Socket实现与html页面的长连接

pom.xml#

<?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> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.3.2.RELEASE</version> <relativePath/>  </parent> <groupId>com.cyb</groupId> <artifactId>socket_test</artifactId> <version>0.0.1-SNAPSHOT</version> <name>socket_test</name> <description>Demo project for Spring Boot</description> <properties> <JAVA.version>1.8</java.version> </properties> <dependencies>  <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-websocket</artifactId> </dependency>  <dependency> <groupId>com.google.guava</groupId> <artifactId>guava</artifactId> <version>18.0</version> </dependency>  <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.46</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </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> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build></project>

Appliccation.properties#

Spring Boot+Socket实现与html页面的长连接

SocketTestApplication.java(Spring Boot启动类)#

Spring Boot+Socket实现与html页面的长连接

WebSocketStompConfig.java#

Spring Boot+Socket实现与html页面的长连接

package com.cyb.socket.websocket;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.web.socket.server.standard.ServerEndpointExporter;@Configurationpublic class WebSocketStompConfig { //这个bean的注册,用于扫描带有@ServerEndpoint的注解成为websocket ,如果你使用外置的Tomcat就不需要该配置文件 @Bean public ServerEndpointExporter serverEndpointExporter() { return new ServerEndpointExporter(); }}

WebSocket.java(Socket核心类)#

Spring Boot+Socket实现与html页面的长连接

package com.cyb.socket.websocket;import java.io.IOException;import java.util.Map;import java.util.Set;import java.util.concurrent.ConcurrentHashMap;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 com.alibaba.fastjson.JSON;import com.alibaba.fastjson.JSONObject;import com.google.common.collect.Maps;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.stereotype.Component;/** * @Author：陈彦斌 * @Description：Socket核心类 * @Date： 2020-07-26 */@Component@ServerEndpoint(value = "/connectWebSocket/{userId}")public class WebSocket { private Logger logger = LoggerFactory.getLogger(this.getClass()); /** * 在线人数 */ public static int onlineNumber = 0; /** * 以用户的姓名为key，WebSocket为对象保存起来 */ private static Map<String, WebSocket> clients = new ConcurrentHashMap<String, WebSocket>(); /** * 会话 */ private Session session; /** * 用户名称 */ private String userId; /** * 建立连接 * * @param session */ @OnOpen public void onOpen(@PathParam("userId") String userId, Session session) { onlineNumber++; System.out.println("现在来连接的客户id：" + session.getId() + "用户名：" + userId); //logger.info("现在来连接的客户id："+session.getId()+"用户名："+userId); this.userId = userId; this.session = session; System.out.println("有新连接加入！当前在线人数" + onlineNumber); // logger.info("有新连接加入！当前在线人数" + onlineNumber); try { //messageType 1代表上线 2代表下线 3代表在线名单 4代表普通消息 //先给所有人发送通知，说我上线了 Map<String, Object> map1 = Maps.newHashMap(); map1.put("messageType", 1); map1.put("userId", userId); sendMessageAll(JSON.toJSONString(map1), userId); //把自己的信息加入到map当中去 clients.put(userId, this); System.out.println("有连接关闭！当前在线人数" + onlineNumber); //logger.info("有连接关闭！当前在线人数" + clients.size()); //给自己发一条消息：告诉自己现在都有谁在线 Map<String, Object> map2 = Maps.newHashMap(); map2.put("messageType", 3); //移除掉自己 Set<String> set = clients.keySet(); map2.put("onlineUsers", set); sendMessageTo(JSON.toJSONString(map2), userId); } catch (IOException e) { System.out.println(userId + "上线的时候通知所有人发生了错误"); //logger.info(userId+"上线的时候通知所有人发生了错误"); } } @OnError public void onError(Session session, Throwable error) { //logger.info("服务端发生了错误"+error.getMessage()); //error.printStackTrace(); System.out.println("服务端发生了错误:" + error.getMessage()); } /** * 连接关闭 */ @OnClose public void onClose() { onlineNumber--; //webSockets.remove(this); clients.remove(userId); try { //messageType 1代表上线 2代表下线 3代表在线名单 4代表普通消息 Map<String, Object> map1 = Maps.newHashMap(); map1.put("messageType", 2); map1.put("onlineUsers", clients.keySet()); map1.put("userId", userId); sendMessageAll(JSON.toJSONString(map1), userId); } catch (IOException e) { System.out.println(userId + "下线的时候通知所有人发生了错误"); //logger.info(userId+"下线的时候通知所有人发生了错误"); } //logger.info("有连接关闭！当前在线人数" + onlineNumber); //logger.info("有连接关闭！当前在线人数" + clients.size()); System.out.println("有连接关闭！当前在线人数" + onlineNumber); } /** * 收到客户端的消息 * * @param message 消息 * @param session 会话 */ @OnMessage public void onMessage(String message, Session session) { try { //logger.info("来自客户端消息：" + message+"客户端的id是："+session.getId()); System.out.println("来自客户端消息：" + message + " | 客户端的id是：" + session.getId()); JSONObject jsonObject = JSON.parseobject(message); String textMessage = jsonObject.getString("message"); String fromuserId = jsonObject.getString("userId"); String touserId = jsonObject.getString("to"); //如果不是发给所有，那么就发给某一个人 //messageType 1代表上线 2代表下线 3代表在线名单 4代表普通消息 Map<String, Object> map1 = Maps.newHashMap(); map1.put("messageType", 4); map1.put("textMessage", textMessage); map1.put("fromuserId", fromuserId); if (touserId.equals("All")) { map1.put("touserId", "所有人"); sendMessageAll(JSON.toJSONString(map1), fromuserId); } else { map1.put("touserId", touserId); System.out.println("开始推送消息给" + touserId); sendMessageTo(JSON.toJSONString(map1), touserId); } } catch (Exception e) { e.printStackTrace(); //logger.info("发生了错误了"); } } /** * 给指定的用户发送消息 * * @param message * @param TouserId * @throws IOException */ public void sendMessageTo(String message, String TouserId) throws IOException { for (WebSocket item : clients.values()) { System.out.println("给指定的在线用户发送消息,在线人员名单：【" + item.userId.toString() + "】发送消息:" + message); if (item.userId.equals(TouserId)) { item.session.getAsyncRemote().sendText(message); break; } } } /** * 给所有用户发送消息 * * @param message 数据 * @param FromuserId * @throws IOException */ public void sendMessageAll(String message, String FromuserId) throws IOException { for (WebSocket item : clients.values()) { System.out.println("给所有在线用户发送给消息，在线人员名单：【" + item.userId.toString() + "】发送消息:" + message); item.session.getAsyncRemote().sendText(message); } } /** * 给所有在线用户发送消息 * * @param message 数据 * @throws IOException */ public void sendMessageAll(String message) throws IOException { for (WebSocket item : clients.values()) { System.out.println("服务器给所有在线用户发送消息，当前在线人员为【" + item.userId.toString() + "】发送消息:" + message); item.session.getAsyncRemote().sendText(message); } } /** * 获取在线用户数 * * @return */ public static synchronized int getOnlineCount() { return onlineNumber; }}

TestController.java(前端控制器)#

Spring Boot+Socket实现与html页面的长连接

package com.cyb.socket.websocket;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.*;import java.io.IOException;@Controller@RequestMapping("testMethod")public class TestController { @Autowired private WebSocket webSocket; /** * 给指定的在线用户发送消息 * @param userId * @param msg * @return * @throws IOException */ @ResponseBody @GetMapping("/sendTo") public String sendTo(@RequestParam("userId") String userId,@RequestParam("msg") String msg) throws IOException { webSocket.sendMessageTo(msg,userId); return "推送成功"; } /** * 给所有在线用户发送消息 * @param msg * @return * @throws IOException * @throws IOException */ @ResponseBody @PostMapping("/sendAll") public String sendAll(@RequestBody String msg) throws IOException, IOException { webSocket.sendMessageAll(msg); return "推送成功"; }}

SocketTask.java(轮询调度往客户端推送消息)#

Spring Boot+Socket实现与html页面的长连接

package com.cyb.socket.schedule;import com.cyb.socket.websocket.WebSocket;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.scheduling.annotation.Scheduled;import org.springframework.stereotype.Component;import java.io.IOException;import java.text.SimpleDateFormat;import java.util.Date;@Componentpublic class SocketTask { @Autowired private WebSocket webSocket; private SimpleDateFormat sdf =new SimpleDateFormat("yyyy-MM-dd HH:mm:ss SSS" ); //5秒轮询一次 @Scheduled(fixedRate = 5000) public void sendClientData() throws IOException { String msg="{"message":"你好","userId":"002","to":"All"}"; webSocket.sendMessageAll(msg); System.out.println("消息推送时间："+ sdf.format(new Date())); }}