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 http://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>2.7.8</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <groupId>com.web.socket</groupId>
    <artifactId>web-socket</artifactId>
    <version>1.0.0</version>

    <properties>
        <java.version>1.8</java.version>
        <spring-boot.version>2.7.8</spring-boot.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-websocket</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.83</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

项目结构 

 websocket主要注解类：

@ServerEndpoint("/im/{username}") 

服务端点（/im/{username}）

ws://127.0.0.1:8080/im/test
@Component   将当前类加入容器中

加上该注解之后不要方法上使用@PathVariable 参数进行接收否则失败

@Data
@Slf4j
@ServerEndpoint("/im/{username}")
@Component
public class WebSocketServerEndpont {

    private static final ConcurrentHashMap<String, Session> sessionMap = new ConcurrentHashMap<>();

    private Session session;

    private String username;

    @OnOpen
    public void onOpen(Session session) {
        Map<String, String> pathParameters = session.getPathParameters();
        String username = pathParameters.get("username");
        this.username = username;
        this.session = session;
        sessionMap.put(username, session);
        log.info("--------用户:{}登录成功，在线人数：{}", username, sessionMap.size());
    }

    @OnClose
    public void onClose() {
        if (sessionMap.containsKey(username)) {
            sessionMap.remove(username);
        }
        log.info("--------用户:{}退出登录，在线人数：{}", username, sessionMap.size());
    }

    @OnMessage
    public void onMessage(Session session, String message) {
        String from = getUserNameBySession(session);
        log.info("--------用户:{}发送信息：{}", from, message);
        sendMessage(message);
    }

    private void sendMessage(String message) {
        String from = getUserNameBySession(session);
        sessionMap.forEach((k, v) -> {
            if (!k.equals(from)) {
                v.getAsyncRemote().sendText(message);
            }
        });
    }

    @OnError
    public void onError(Session session, Throwable throwable) {

    }

    private String getUserNameBySession(Session session) {
        return session.getPathParameters().get("username");
    }

}

启动：使用websocket在线工具: ws://127.0.0.1:8080/im/test,开启两个浏览器即可实现聊天

关于部署到linux 访问不到的问题：

首先ssl 证书要配置好。

nginx配置：

upstream  sockets {
    server 127.0.0.1:8080 max_fails=3 fail_timeout=10s; 
}
server {
    listen 443 ssl;
    server_name 域名;
    #调整成自己的证书即可，重点重点重点
    ssl_certificate /etc/nginx/cert/ssl.pem;
    ssl_certificate_key /etc/nginx/cert/ssl.key;
    ssl_session_timeout 5m;
    #通过location进行处理，重点重点重点
    location / {
      proxy_pass http://sockets;
      proxy_http_version 1.1;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection "upgrade";
    }
    error_page 404 /404.html;
}

服务地址要使用：wss://域名/im/test