PowerBuilder 9 Internet and Distributed Application Development, by William Green and John D. Olson, ISBN 0-672-32499-7

Reviewed by: Songmuh Jong, send e-mail Published by: Sams Publishing, go to the web site Requires: PowerBuilder 9 with EAServer, iAnywhere m-Business Studio and Sybase Enterprise Portal MSRP: $49.99 It is exciting to see a book dedicated to Internet and Distributed Application Development using PowerBuilder. If you scan the book quickly, you'll find a lot of text discussing EAServer rather than PowerBuilder and many readers may have already turned away from the book that reason. However it's a misconception carried over from the client/server role of PowerBuilder that it has to play a prominent role in the application development process. This is no longer true in the distributed or web development where many components play their roles in harmony. What's the role of PowerBuilder in Internet and Distributed Application Development? The book does not provide a straightforward answer to this question. However, one can summarize from various chapters as the follows: (1) Create Web Datawindows (chapter 7); (2) Import and export XML datawindows (chapter 8, 20); (3) Create objects for deployment to EAServer (chapter 5, 9); (4) Create proxy and call web services (chapter 21); (5) Create EJB proxy to access EJB servers (chapter 23). One unlikely role mentioned in the book (and not fully explained) is to create PowerBuilder objects wrapped for other servers. As discussed in chapter 4, it is a question whether to migrate PowerBuilder applications or to rewrite in Java. From the business point of view, it makes sense to do incremental rewrites rather than full rewrites of existing applications. During the transition period, PowerBuilder is still valuable as a rapid development tool to interface with other platforms. Unless Java comes up with a rapid development framework, it is impossible for Java to replace PowerBuilder in the business world. It is also obvious that PowerBuilder will be more and more restricted in terms of its accessibility to the database servers. PowerBuilder has to operate through application servers or web servers in the distributed world. From this book, it is also apparent that Sybase will not make PowerBuilder function as an application server or web server.

Aside from the PowerBuilder discussion, the book is full of EAServer configuration and troubleshooting guides. However, this is not an EAServer book. If you expect a systematic guide to EAServer, you'll be disappointed. For someone who already has experience running EAServer however, this is still an informative book. Chapter 3 is an overview, chapter 12 deals with EAServer multithreading, chapter 15 on Deployment, and chapters 16 to 19 are about EAServer administration, monitoring and caching.

The most exciting chapter in this book is the one on mobile systems (chapter 22). Berndt Hamboeck does an excellent job of describing the background of mobile computing and shows you how to create a WAP page. He also discusses Sybase iAnywhere m-Business System and Enterprise Portal. The SQL features are also intriguing. Other chapters on distributed computing (chapters 1, 2, 6), application migration (chapter 4), web services (chapter 21), and EJB (chapter 23) are well written and very informative too.

If there is any shortcoming to this book, it is the organization of topics that sometimes require readers to jump between chapters. XML datawindows is discussed (chapter 8) before the XML development (chapter 20). The same topic "What is XML" is duplicated in both chapters 8 and 20. It is interesting that chapter 8 states that "... are discussed in detail in the book's sister publication: PowerBuilder Internet and Distributed Application Development (Sams Publishing, 2003), by William Green and John D. Olson," which is this book! The chapter on web services mentions a companion CD with Apache axis, but there is no companion CD supplied with the book.

This is the most up-to-date PowerBuilder companion on distributed and web development so far. The authors have put together an informative volume that should be helpful for PowerBuilder developers and any other web developers. The power of EAServer is demonstrated in many places in the book. IT managers who read some of the chapters may change their view of the next phase of application migration or rewrites. Readers who have been disappointed by a cursory skim of the book should re-read it in order to discover its hidden treasures. Recommended.

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