一、添加依赖

<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-websocket</artifactId>
        </dependency>
        <!--websocket-->
        <dependency>
            <groupId>io.goeasy</groupId>
            <artifactId>goeasy-sdk</artifactId>
            <version>0.4.2</version>
        </dependency>

二、具体步骤

1. 建立连接：通过调用 WebSocket 对象的 open() 方法来建立与服务器的连接。

2. 发送数据：通过调用 WebSocket 对象的 send() 方法来向服务器发送数据。

3. 接收数据：通过 WebSocket 对象的 onmessage 事件来接收服务器发送回来的数据。

4. 关闭连接：通过调用 WebSocket 对象的 close() 方法来关闭与服务器的连接

三、代码实例 

@Configuration
@EnableWebSocket
public class WebSocketConfig implements WebSocketConfigurer {

    //建立两个链接
    private final MyWebSocketHandler myWebSocketHandler;
    private final MyWebSocketHandler1 myWebSocketHandler1;


    public WebSocketConfig(MyWebSocketHandler myWebSocketHandler, MyWebSocketHandler1 myWebSocketHandler1) {
        this.myWebSocketHandler = myWebSocketHandler;
        this.myWebSocketHandler1 = myWebSocketHandler1;
    }

    @Override
    public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
        //分别监听不同的实例
        registry.addHandler(myWebSocketHandler, "/websocket")
                .setAllowedOrigins("*");
        registry.addHandler(myWebSocketHandler1, "/websocket2")
                .setAllowedOrigins("*");
    }
}

 这里以监听字符串为例子（可以选择监听文件等）

@Component
public class MyWebSocketHandler extends TextWebSocketHandler {
    private WebSocketSession session;
    public static String logContent = ""; // 字符串内容
    private long lastLength = 0; // 上次记录的字符串长度


    @Override
    public void afterConnectionEstablished(WebSocketSession session){
        // 处理WebSocket连接建立的逻辑
        this.session = session;

        // 启动字符串监控线程
        Thread stringMonitoringThread = new Thread(() -> {
            while (true) {
                if (logContent.length() > lastLength) {
                    String modifiedContent = logContent.substring((int) lastLength); // 获取新增的字符串内容
                    try {
                        session.sendMessage(new TextMessage(modifiedContent)); // 发送新增的内容到前台
                        logContent="";
                    } catch (IOException e) {
                        throw new RuntimeException(e);
                    }
                    lastLength = logContent.length(); // 更新上次记录的字符串长度
                }
                try {
                    Thread.sleep(1000); // 每隔一秒检查一次
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        });
        stringMonitoringThread.start(); // 启动字符串监控线程
    }

    @Override
    protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {
        // 处理接收到的WebSocket消息的逻辑
        System.out.println("接收到WebSocket消息：" + message.getPayload());
    }

    @Override
    public void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception {
        // 处理WebSocket连接关闭的逻辑
        System.out.println("WebSocket连接已关闭");
    }


}

模拟用法

 @PostMapping("/send")
    public void send(@RequestBody SourceTypeResponse sourceTypeResponse){
        log.info(JSONObject.toJSONString(sourceTypeResponse));
        
        if (sourceTypeResponse.getPageNum()==1){
            MyWebSocketHandler.logContent= "警告";
        }

    }

四、前台展示 

mounted() {
			const socket = new WebSocket('ws://127.0.0.1:8087/websocket')
			socket.onopen = () => {
				console.log('WebSocket连接已建立')
			}
			socket.onmessage = event => {
				const logMessage = event.data
				console.log(logMessage)
				this.logs.push(logMessage) // 将日志消息存储到数组中
			}

			socket.onclose = () => {
				console.log('WebSocket连接已关闭')
			}

			socket.onerror = error => {
				console.error('WebSocket发生错误:', error)
			}
    },

<div>
		<h1>WebSocket日志</h1>
		<ul>
			<li v-for="log in logs" :key="log">{{ log }}</li>
		</ul>
	</div>

五、效果展示