Java Message Service

Name

JMSExpiration — Purpose: Routing

Synopsis

A Message object can have an expiration date, the same as on a carton of milk. The expiration date is useful for messages that are only relevant for a fixed amount of time. For example, the B2B example developed in Chapter 4, and Chapter 5, might use expiration dates on messages representing “Hot Deals” that a wholesaler extends to retailers. The “Hot Deal” is only valid for a short time, so the Message that represents a deal expires after that deadline.

The expiration time for messages is set in milliseconds by the producer using the setTimeToLive( ) method on either the QueueSender or TopicPublisher as shown below:

// Publish-and-subscribe
TopicPublisher topicPublisher = topicSession.createPublisher(topic);
// Set time to live as 1 hour (1000 millis x 60 sec x 60 min)
topicPublisher.setTimeToLive(3600000);

// Point-to-point
QueueSender queueSender = queueSession.createSender(topic);
// Set time to live as 2 days (1000 millis x 60 sec x 60 min x 48 hours)
queueSender.setTimeToLive(172800000);

By default the timeToLive is zero, which indicates that the message doesn’t expire. Calling setTimeToLive( ) with a zero value as the argument ensures that message is created without an expiration date.

The JMSExpiration date itself is calculated as:

JMSExpiration = currenttime + timeToLive.

The value of the currenttime is the amount of time, measured in milliseconds, that has elapsed since the Java epoch (midnight, January 1, 1970, UTC).

The JMS ...