Question

您好我已将此WebListener类添加到我的webproject

@WebListener
public class SelfSend implements ServletContextListener {

    private MessageProducer producer;
    private Connection sendconnection;
    private Connection receiveconnection;
    private Session sendsession;
    private Session receivesession;
    private MessageConsumer receiver;

    @Override
    public void contextInitialized(ServletContextEvent arg0) {
        try {
            InitialContext initCtx = new InitialContext();
            ConnectionFactory connectionFactory = (ConnectionFactory) initCtx.lookup("java:comp/env/jms/ConnectionFactory");
            sendconnection = connectionFactory.createConnection();
            receiveconnection = connectionFactory.createConnection();
            sendsession = sendconnection.createSession(false, Session.AUTO_ACKNOWLEDGE);
            receivesession = receiveconnection.createSession(false, Session.AUTO_ACKNOWLEDGE);
            producer = sendsession.createProducer((Destination) initCtx.lookup("java:comp/env/jms/queue/MyQueue"));
            receiver = receivesession.createConsumer((Destination) initCtx.lookup("java:comp/env/jms/queue/MyQueue"));
            receiver.setMessageListener(new MessageListener() {
                @Override
                public void onMessage(Message message) {
                    System.out.println("MESSAGE RECEIVED");

                }
            });
            TextMessage testMessage = sendsession.createTextMessage();
            testMessage.setStringProperty("from", "ki");
            producer.send(testMessage);
            System.out.println("MESSAGE SENT");
        } catch (Exception e) {
            throw new RuntimeException(e);
        }

    }

    @Override
    public void contextDestroyed(ServletContextEvent arg0) {

    }

}

但是从未收到过该消息。

当我把reciver放在像这样的@WebServlet

时

@Override
public void init(ServletConfig config) throws ServletException {
    super.init(config);
    try {
        InitialContext initCtx = new InitialContext();
        ConnectionFactory connectionFactory = (ConnectionFactory) initCtx.lookup("java:comp/env/jms/ConnectionFactory");
        connection = connectionFactory.createConnection();
        connection.start();
        session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
        receiver = session.createConsumer((Destination) initCtx.lookup("java:comp/env/jms/queue/MyQueue"));
        receiver.setMessageListener(this);
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
    mud = new MongoUserdata();
}

我收到了这条消息，当我把它放入我只收到Servlet-Receiver的每一条消息时，另一个消息似乎丢失了。

有人能向我解释这种奇怪的行为吗？

Answer 1

在您的第一个示例课程中，您似乎没有启动接收器连接，这意味着它不会发送任何收到的消息。然而，它将保留消费者预取缓冲区中的传入消息，从而导致您遇到的每个其他消息接收。

ActiveMQ无法接收我的消息

1 个答案: