java – 如何等待Spring WebSocketStompClient连接

我使用this guide来实现一个简单的Stomp客户端：

WebSocketClient webSocketClient = new StandardWebSocketClient();
WebSocketStompClient stompClient = new WebSocketStompClient(webSocketClient);

ThreadPoolTaskScheduler taskScheduler = new ThreadPoolTaskScheduler();
taskScheduler.afterPropertiesSet();
stompClient.setTaskScheduler(taskScheduler); // for heartbeats

stompClient.setMessageConverter(new StringMessageConverter());

StompSessionHandler sessionHandler = new MySessionHandler();
stompClient.connect("ws://server/endpoint", sessionHandler);

// WAITING HERE

当连接完成时,它应该异步向MySessionHandler报告：

public class MySessionHandler extends StompSessionHandlerAdapter
{
     @Override
     public void afterConnected(StompSession session, StompHeaders connectedHeaders) 
     {
         // WAITING FOR THIS
     }
}

所以问题是：在这里等待等待线路的线路如何等待？是否有一种特定的Spring方式来做到这一点？如果没有,哪种通用Java方式最适合这里？

解决方法:

也许java.util.concurrent.CountDownLatch可以像这样解决你的问题：

CountDownLatch latch = new CountDownLatch(1);
StompSessionHandler sessionHandler = new MySessionHandler(latch);
stompClient.connect("ws://server/endpoint", sessionHandler);
// wait here till latch will be zero
latch.await();

和你的MySessionHandler实现：

public class MySessionHandler extends StompSessionHandlerAdapter {
    private final CountDownLatch latch;

    public MySessionHandler(final CountDownLatch latch) {
        this.latch = latch;
    }

    @Override
    public void afterConnected(StompSession session, 
                               StompHeaders connectedHeaders) {
        try {
            // do here some job
        } finally {
            latch.countDown();
        }
    }
}

标签：spring-websocket,java,multithreading,spring,concurrency
来源： https://codeday.me/bug/20190727/1554243.html