Consumer not consuming messages when created dynamically - activemq

Question

I am learning to implement active mq interface in my project. This is how I am creating producers and consumers.
public void connectionSetup(String portName) { // portname is object of PortTO class. We are creating producer and consumer pair for every existing PortTO object.
Connection connection = null;
try {
if (timeToLive != 0) {
}
// Create the connection.
ActiveMQConnectionFactory connectionFactory = new ActiveMQConnectionFactory(user, password, url);
connection = connectionFactory.createConnection();
connection.start();
connection.setExceptionListener(this);
// Create the session
Session session = connection.createSession(transacted, Session.AUTO_ACKNOWLEDGE);
if (topic) {
destination = session.createTopic(subject);
} else {
destination = session.createQueue(portName);
}
// Create the producer.
MessageProducer producer = session.createProducer(destination); if (persistent) {
producer.setDeliveryMode(DeliveryMode.PERSISTENT);
} else {
producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
}
MessageConsumer consumer = session.createConsumer(destination); if (timeToLive != 0)
producer.setTimeToLive(timeToLive);
mapOfSession.put(portName, session);
mapOfMessageProducer.put(portName, producer);
mapOfMessageConsumer.put(portName, consumer); log.info("Producer is " + producer);
log.info("Consumer is " + consumer);
} catch (Exception e) {
log.error(e.getMessage());
}
}
So, we are creating producer and consumer and storing them in a map for every PortTO object. Now, producer is sending messages:
TextMessage message = session.createTextMessage();
message.setIntProperty(key, 2);
producer.send(message);
But consumer is not consuming it...
public void onMessage(Message message) {
PortService portService = new PortService();
List<PortTO> portTOList = portService.getMoxaPorts();
for(PortTO portTO : portTOList) { // catching messages from producers of every PortTO object
MessageConsumer consumer = DataCollectionMessageProducer.getMapOfMessageConsumer().get(portTO.getPort()); // getting consumer from map of PortTO
consumer.setMessageListener(this);
message = consumer.receive(1000); if (message instanceof TextMessage) {
/ / some processing
}
} else {
if (verbose) {
}
}
}
}
What can be the reason? Is my approach wrong ??

Answer 1

You are setting the messageListener in the onMessage method. This is a catch 22, since the onMessage method gets invoked only if the messageListener is set to that object.
Another thing, I am not sure why you would do a receive in a message listener. The onMessage will be invoked for each message on the queue once it has been set as listener and the logic for each received message should reside in there in an event driven fashion. At least, that is the idea with JMS in the first place