ActiveMQ-保留消耗的消息，直到确认删除为止

Question

I have an Spring Boot app that is listening to a ActiveMQ queue.

Is there a way to tell ActiveMQ to keep consumed messages until it's received acknowledgement to delete the message from my service?

My scenario is I read message from queue and once consumed, I'm sending it to an external queue. If the external service fails to process the message, I would loose the message. Is there away I can tell active mq to hold onto consumed message until it's received an acknowledgement to delete.

Answer 1

The safest option would be to use an XA transaction to perform the consume/send atomically (assuming the broker where you're sending the message supports XA). I'm not sure how easy or hard that is in Spring, but I know it's pretty simple in a Java EE container.

Answer 2

You can use the individual acknowledge mode which ack the single message. Below is the code for same:

    import javax.jms.Connection;
    import javax.jms.JMSException;

    import org.apache.activemq.ActiveMQConnectionFactory;
    import org.apache.activemq.ActiveMQMessageConsumer;
    import org.apache.activemq.ActiveMQSession;
    import org.apache.activemq.command.ActiveMQTextMessage;

    public class SimpleConsumer {

        public static void main(String[] args) throws JMSException {
            Connection conn = null;
            try {
                ActiveMQConnectionFactory cf = new ActiveMQConnectionFactory("tcp://localhost:61616");
                conn = cf.createConnection("consumer", "consumer");
                ActiveMQSession session = (ActiveMQSession) conn.createSession(false,
                        ActiveMQSession.INDIVIDUAL_ACKNOWLEDGE);
                ActiveMQMessageConsumer consumer = (ActiveMQMessageConsumer) session
                        .createConsumer(session.createQueue("QUEUE"));
                conn.start();
                ActiveMQTextMessage msg = null;
                while ((msg = (ActiveMQTextMessage) consumer.receive()) != null) {
                    System.out.println("Received message is: " + msg.getText());
               // Call your service and ack the message if successfully processed                    
                 msg.acknowledge();
                }
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                if (conn != null) {
                    try {
                        conn.close();
                    } catch (Exception e) {
                    }
                }
            }
        }
    }