Advanced Queuing - Oracle

JMS Message Producer Features
}
Message Grouping
obj_message.setObject(back_order);
tpub = jms_session.createPublisher(null);
/* Set message expiration to 7 days: */
timetolive = 7*60*60*24*1000; // specified in milliseconds
/* Publish the message */
tpub.publish(back_order_topic, obj_message, DeliveryMode.PERSISTENT,
1, timetolive);
jms_session.commit();
}
catch (Exception ex)
{
System.out.println("Exception :" + ex);
}
Messages belonging to a queue/topic can be grouped to form a set that can only be
consumed by one consumer at a time. This requires the queue/topic be created in a
queue table that is enabled for transactional message grouping (see "Creating a
Queue Table", Chapter 9, "Administrative Interface"). All messages belonging to a
group have to be created in the same transaction and all messages created in one
transaction belong to the same group. Using this feature, you can segment a
complex message into simple messages. This is an AQ extension and not part of the
JMS specification.
For example, messages directed to a queue containing invoices could be constructed
as a group of messages starting with the header message, followed by messages
representing details, followed by the trailer message. Message grouping is also very
useful if the message payload contains complex large objects such as images and
video that can be segmented into smaller objects.
The general message properties (priority, delay, expiration) for the messages in a
group are determined solely by the message properties specified for the first
message (head) of the group irrespective of which properties are specified for
subsequent messages in the group.
12-62 Oracle9i Application Developer’s Guide - Advanced Queuing