November 2005
Intermediate to advanced
896 pages
31h 5m
English
Content preview from Java Enterprise in a Nutshell, Third Edition
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
The Anatomy of Messages
Creating a messaging-based application involves more than establishing communication channels between participants. Players in a message-driven system need to understand the content of the messages and know what to do with them.
Native messaging systems, such as WebSphere MQ or Microsoft MQ (MSMQ), define their own proprietary formats for messages. JMS attempts to bridge these native messaging systems by defining its own standard message format. All JMS clients can interact with any messaging system that supports JMS. “Supports” in this case can mean one of two things. The messaging system can be implemented in a native, proprietary architecture, with a JMS bridge that maps the JMS message formats (and other aspects of the JMS specification) to the native scheme and back again. Or the messaging system can be written to use the JMS message format as its native format.
JMS messages are made up of a set of standard header fields,
optional client-defined properties, and a body. JMS also provides a
set of subclasses of Message that
support various types of message bodies.
Message Header Fields and Properties
Table 11-1 lists the standard header fields that any JMS message can have. The table indicates the name and type of the field, when the field is set in the message delivery process, and a short description of the semantics of the field.
Table 11-1. Standard JMS message headers
Field name | Data type | When set | Description |
|---|---|---|---|
JMSCorrelationID | String | Before send | Correlates ... |
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.