Java Message Service, 2nd Edition

Name

JMSReplyTo — Purpose: Routing

In some cases, a message producer may want the consumers to reply to a message. The JMSReplyTo header indicates which destination, if any, a JMS consumer should reply to. The JMSReplyTo header is set explicitly by the JMS client; its contents will be a javax.jms.Destination object (either Topic or Queue).

In some cases, the JMS client will want the message consumers to reply to a temporary topic or queue set up by the JMS client. Here is an example of a pub/sub JMS client that creates a temporary topic and uses its Topic object identifier as a JMSReplyTo header:

TopicSession session = 
connection.createTopicSession(false, Session.AUTO_ACKNOWLEDGE);
...
Topic tempTopic = session.createTemporaryTopic();
...

TextMessage message = session.createTextMessage();
message.setText(text);
message.setJMSReplyTo(tempTopic);
publisher.publish(message);

When a JMS message consumer receives a message that includes a JMSReplyTo destination, it can reply using that destination. A JMS consumer is not required to send a reply, but in some JMS applications, clients are programmed to do so. Here is an example of a JMS consumer that uses the JMSReplyTo header on a received message to send a reply. In this case, the subscriber will simple send an acknowledgment back to the publisher indicating it received the message:

Topic chatTopic = ... get topic from somewhere ... // Publisher is created without a specified Topic TopicPublisher publisher = session.createPublisher(null); ...