spring boot jms-在@JMSListner内部发送和接收消息

Question

到目前为止我有下一个：

    @JmsListener(destination = QUEUE_IN, selector = "type='com.example.MainRequest")
    public void receiveMessage(Message message) throws JMSException {
        LOG.info("Received {} <{}>", QUEUE_IN, message);
        jmsTemplate2.convertAndSend(QUEUE_OUT, "SUB Request", requestMsg -> {
            requestMsg.setStringProperty("type", "com.example.SubRequest");
            return requestMsg;
        });
        LOG.info("Message sent");
        Message reply = jmsTemplate2.receiveSelected(QUEUE_IN, "type='com.example.SubResponse'");
        LOG.info("Received reply from {}: <{}>", QUEUE_IN, reply);
    }

我被“已发送消息”困住了。看起来子请求没有真正发送。我在MQ UI中看到队列深度为1，但内部没有消息，并且我的子请求侦听器也没有看到任何消息。

我还尝试使用sendandreceive方法：

Message reply = jmsTemplate.sendAndReceive(QUEUE_OUT, session -> {
    Message msg = session.createTextMessage();
    msg.setStringProperty("type", "com.example.SubRequest");
    LOG.info("Sending msg: <{}> to {}", msg, QUEUE_OUT);
    return msg;
});

启用事务开始/结束日志也很有帮助：

logging:
  level:
    org.springframework.transaction.interceptor: trace

Answer 1

出站邮件发送方与邮件接收方注册在同一事务中。因此出站消息的接收者在事务提交之前不会看到消息。我认为您需要启动一个新的事务来执行内部过程。

==更新==

所以这已经有一段时间了，我没有为此设置一个开发环境，但我建议使用类似这样的方法。本质上，您将侦听器和发送器/接收器分成两个单独的类。发送者/接收者应该被注入到您的侦听器中，这样@transactional注释就会得到尊重。

public class MyListener {
    private final MySender sender;

    public MyListener(MySender sender) {
        this.sender = sender;
    }

    @JmsListener(destination = QUEUE_IN, selector = "type='com.example.MainRequest")
    public void receiveMessage(Message message) throws JMSException {
        LOG.info("Received {} <{}>", QUEUE_IN, message);
        Message reply = sender.sendAndReceive()
        LOG.info("Received reply from {}: <{}>", QUEUE_IN, reply);
    }
}


public class MySender {
    private final JmsTemplate jmsTemplate2;
    private final Destination QUEUE_OUT;

    public MySender(JmsTemplate jmsTemplate2, Destination QUEUE_OUT) {
        this.jmsTemplate2 = jmsTemplate2;
        this.QUEUE_OUT = QUEUE_OUT;
    }

    @Transactional(propagation=Propagation.NESTED)  // Or REQUIRES_NEW, edepending on usage
    public Message sendAndReceive() throws JMSException {
        jmsTemplate2.convertAndSend(QUEUE_OUT, "SUB Request", requestMsg -> {
            requestMsg.setStringProperty("type", "com.example.SubRequest");
            return requestMsg;
        });
        LOG.info("Message sent");
        Message reply = jmsTemplate2.receiveSelected(QUEUE_IN, "type='com.example.SubResponse'");
        LOG.info("Received reply from {}: <{}>", QUEUE_IN, reply);
        return reply;
    }
}