Creating Message Consumer to a Topic 

The message consumer for a topic connection is TopicSubscriber. The topic subscriber must be applied to a topic at creation time. You can choose to use the TopicSubscriber in two ways:

·        To register the class as javax.jms.MessageListener instance for asynchronous message reception.

·        To use it to receive messages synchronously.

 

If you want to receive messages asynchronously, you must register the class as a javax.jms.MessageListener instance. This enables you to receive and unpack the messages using the onMessage(javax.jms.Message message) method:

// create subscriber to a topic TopicSubscriber topicSubscriber = topicSession.createSubscriber(topic);   // set message listener topicSubscriber.setMessageListener( this );   public void onMessage(javax.jms.Message message) { // receive and unpack the message

For an example source on receiving messages asynchronously, see Asynchronously Receiving Messages Sent to a Topic.

If you want to receive messages synchronously, use the receive() method. Apply it to the message you want to receive.

 

// create subscriber to a topic TopicSubscriber topicSubscriber = topicSession.createSubscriber(topic);           // receive the message TextMessage textMessage =  (TextMessage) topicSubscriber.receive();

For an example source on receiving messages synchronously, see Synchronously Receiving Messages Sent to a Topic.