Book Review

JBoss - A Developer's Notebook

Abstract

Controversies aside, JBoss has emerged as a credible alternative to commercial J2EE App Servers for developing and deploying Java based server applications. Besides the usual advantages of open source and GPL licensing, what sets it apart is its JMX based microkernel, a light-weight framework to run independently developed Java programs within a single JVM. Together, these make it possible for one to pick and choose components and assemble a custom server anywhere between the two extremes (and beyond!) of a simple Servlet Container and a full-fledged J2EE Server.

JBoss - A Developer's Notebook by Norman Richards, a JBoss developer at JBoss, Inc., and Sam Griffith, Jr., a software consultant and trainer, is a no-fluff How-To guide on doing stuff with JBoss in O'Reilly's new Developer Notebook format. True to the format, this book doesn't waste pages on paeans of architectural elegance, internal design or conceptual deliberations, and limits itself to the basic needs of most professionals -- how do I do this or that with JBoss, where to start, what steps to carry out or what code to write, and what happens behind the curtains.

Books dealing with J2EE products tend to be fat and bulky, but this (note)book doesn't fall in that category. By covering only JBoss specific aspects and avoiding general J2EE topics, this rather thin book has managed to include a good deal of difficult-to-find information about JBoss. In fact, while going through its pages, I got a feeling that the authors have taken care to be different and complementary to the online documentation available in JBoss Application Server Guide and JBoss Wiki.

In support of the above claim, let me compare the coverage of how to deploy applications under JBoss, an important activity with any J2EE container, in the JBoss Guide, JBoss Wiki, and the book under review. The JBoss Guide covers application deployment as part of the JMX based microkernel architecture and design, describing, in excruciating detail, the internal components responsible for the deployment and and how they interact. The JBoss Wiki takes a more externally focussed approach, talking about hot deployment capability, relevant directories and configuration files in an installed system, and steps in a typical deployment process. In contrast, the JBoss - A Developer's Notebook goes through the whole process of creating the deployable WAR file for a web application, deploying that to JBoss by copying the created file to JBoss's deploy directory, and verifying successful deployment or looking for errors. It even talks about how to modify a deployed application. Needless to say, the last one is most useful to someone who just wants to deploy his or her application.

True to its lab notebook style, the book makes important, though not integral, observations about specific topics in the page margins. For example, a note in the margin of deployment steps tells you that you can include a deployment package within another deployment package, upto an arbitrary level of nesting, a la Russian Doll Packaging way. I found this informal way of communicating relevant stuff quite effective.

Another noteworthy aspect of this book is that it makes generous use of appropriate tools, such as Ant and XDoclet, to get things done. This can be either good or bad, depending upon your familiarity with these tools. For me, it turned out to be a mixed bag. I know Ant and am happy writing Ant scripts for packaging and deployment. It is different with XDoclet, which I haven't had a chance to use so far. But perhaps the authors know better and one should just get familiar with it before working on any project involving JBoss and Enterprise Java Beans.

It is difficult, if not impossible, to cover each and every aspect of a software as feature rich and complex as JBoss in any single book. This leaves the somewhat unpleasant task of choosing topics to the the authors and editors, for the selection may or may not match the needs of a particular reader. At the same time, it increases the responsibility of a reviewer like me who must help a propspective buyer decide for or against making a purchase, based on her needs.

Let me attempt to do that by making two lists: first, what is included and then, what is not.

What is included (paraphrased Table of Contents):

• How to install, start, examine (through JMX Console) and shutdown JBoss Server.
• How to package, deploy, observe and undeploy an application.
• How to create a web application with database access and user authentication.
• How to use MySQL as database for a JBoss application.
• How to setup user database, login modules and enable SSL.
• How to configure logging for various components of JBoss.
• How to map schema, objects and relations to database tables.
• How to monitor and manage a JBoss application with MBeans.
• How to create a custom JBoss with modules that your application needs.

A similar, comprehensive, list of what is not included is simply not possible. Still, I have gone ahead and created the following based on my experience with JBoss. Keep in mind that these reflect the kind of applications I have worked on and may not be representative of your needs.

• How to use JBoss as a J2SE container.
• How to develop Web services with JBoss.
• How to create, package and deploy an application consiting of JBoss services, web applications and web services.
• How to troubleshoot class loading problems.
• How to isolate applications within a single JBoss server instance.
• How to profile for performance bottlenecks.
• How to run multiple instances of JBoss Server on a single machine.

I can only hope that the authors will take this as a reader feedback and include some of the above in a future edition.

So, what else is there not to like about this book? One thing that caught my attention was the relative absence of insight into why things worked the way they worked, what were the underlying patterns and how can the awareness about these patterns be applied to other similar situations. These are the things I look for in a new product or technology and have found them to be much more helpful than just a compilation of step-by-step descriptions of doing things. Perhaps the Developer's Notebook format doesn't allow for such digressions, still I think inclusion of such insights would have improved the book.

Overall, I would say that JBoss - A Developer's Notebook is a good introductory book for those who are thinking of getting started or are just getting started with JBoss. If you have already worked on JBoss and are looking for more advanced or esoteric stuff, then this book is perhaps not for you.

© 2005 by Pankaj Kumar. All Rights Reserved. You may use the content of this article, including the source code, in your programs and documentation. In general, you do not need to contact me for permission unless you are reproducing a significant portion of the article or code for commercial purposes. For example, writing a program that uses the code for personal or company use does not require permission. Republishing this article, even with proper attribution, does require permission. Similarly, incorporating the code in a program that you sell for profit requires permission.

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You can contact me by sending e-mail to pankaj.kumar@gmail.com.