In JMS asynchronous message handling as soon as onMessage() is called, message deleted from queue

Question

Requirement: I want messages to be persist in queue till onMessage() executed successfully. If any exception occur during execution of onMessage() and if it is not handle then message should be redelivered to listener.

I am having Glassfish v2 as a application server. I am using OpenMQConnectionFactory and JmsTemplate to send message on queue. Please note that I am not using MDB.

<bean id="openMQConnectionFactory"
    class="com.is.br.util.OpenMqConnectionFactoryBean">
    <property name="imqAddressList" value="mq://localhost:7676" />
    <property name="imqDefaultUsername" value="admin" />
    <property name="imqDefaultPassword" value="admin" />
</bean>

I tried AUTO_ACKNOWLEDGE as acknowledge mode but in listener when exception thrown message is not redelivered.

MessageProducer.java

public void sendMessage(final String responseStream) {

    System.out.println("Enter into IsJmsProducer.sendMessage method");

    try {
        MessageCreator creator = new MessageCreator() {
            public Message createMessage(Session session) {
                ObjectMessage message = null;
                try {
                    message = session.createObjectMessage(responseStream);
                    } catch (Exception e) {
                    System.out.println("Unable create a JMSMessage");
                }
                return message;
            }
        };

        System.out.println("Sending message to destination: " + this.destination.toString());
        this.jmsTemplate.setSessionAcknowledgeMode(Session.AUTO_ACKNOWLEDGE);

        this.jmsTemplate.send(this.destination, creator);
        System.out.println("SendMessage to queue successfully.");           
    } catch (Exception ex) {
        System.out.println("SendMessage to queue Fail." + ex);
    }
    System.out.println("Exit from IsJmsProducer.sendMessage method");

}

SampleJMSConsumer.java

public class SampleJMSConsumer implements MessageListener {

    @Override
    public void onMessage(Message message) {
        throw new RuntimeException();
   }
}

Then I tried with this.jmsTemplate.setSessionAcknowledgeMode(Session.CLIENT_ACKNOWLEDGE); and in listener I called message.acknowledge(); and in catch block I called session.recover() still message is not redeliver.

SampleJMSConsumer.java

public class SampleJMSConsumer implements MessageListener  {

    @Override
    public void onMessage(Message message) {

        ObjectMessage objectMessage = (ObjectMessage) message;
        Object object;
        try {
            object = objectMessage.getObject();
            if (object instanceof String) {
                System.out.println("Message received - " + object.toString());
                throw new JMSException("JMS exception");
            }
            message.acknowledge();
        } catch (JMSException e) {
               session.recover();
        }
    }

}

When I run the program in debug mode and I send message on queue in broker admin console I am able to see the number of messages but as soon as onMessage() called number of messages get reduce by one. That means message is consumed and deleted from queue. Is that message consider as "delivered"? Please help me to understand why message is not redeliver when exception occur?

Thanks in advance.

Answer 1

I think this is by design, delivered when onmessage gets called. If you want do something about the exception you might handle it using try catch.

Assume the message was put on the queue once again, you wouls likely hit the same exception when consumed anyways.

The ack mechanisms should imo be about assuring correct delivery. Maybe what you are after is a reject mechanism where you ask the prpoducerside to send a new message?