This book is part of Sun' `The Java Series' and has the same content as you can find online at Sun' site. Why buy a book you can get for free? Convenience!! You can take it anywhere and read it anytime and printing all 450+ pages off of the internet onto 8 1/2" X 11" paper is not feasible.
The content of the book is thorough and covers the uses and implementations of the various J2EE parts in depth. Where the book really excels above other Enterprise Java books is in describing the deployment process and how the different J2EE concepts all work together to create a single application.
The authors give very detailed, step by step instructions on exactly how to use the deploy tool to create the various deployment files (WARs, JARs, web.xml, etc.). at each stage in the book they show you the exact steps needed to compile and then package the various pieces of the application into a deployable form that can be used as a real, working application.
The book references a complete sample project that is included on the CD. This complete project makes it easier to understand the various concepts and how they all tie together. This is as opposed to other Enterprise books that use a separate example for each topic and never show the technologies used together. The only noticeable drawback of this approach is that the code samples presented are usually snippets from larger classes and can not be used alone for a reader to practice and play with.
At times I found the flow of the book hard to follow and only after reading a page or two into a chapter or section did I understand the direction the author was headed. This is most likely a result of having multiple authors for the book and encountering different styles at different times.
Most readers will get the best value out of the book in learning the details of the deployment process along with other related concepts and steps. The second most valuable lesson is the big picture view you get of an entire web application. You won't find useful code samples to play and experiment with but those can be found in most other books. Which is why using this book in conjunction with another is probably the best way to go. No one uses just one book to study with - so find your favorite other Enterprise Java book with good workable samples and then use this as a compliment to it.
