Preface

In 1999, a couple of guys got together and decided to start an open source EJB container project. Six years later, we have JBoss 4.0, and the difference between that early version and this one is a lot greater than a few version numbers might suggest. While JBoss is still an open source community-driven project, it is much more than just an EJB container. JBoss 4.0 is a full J2EE 1.4-certified application server. It is competitive with proprietary application servers in terms of features and quality, and has risen to be the number one application server in terms of overall market share. There's definitely something special about it.

JBoss isn't any ordinary open source project. It's one of the few open source projects that have found commercial success without betraying their open source roots. JBoss is backed by JBoss, Inc., a successful and rapidly growing company with more than 100 full-time employees fueling the continued development of the project. Although JBoss is freely available for any purpose, it is backed by a real company that provides support and training for those who need the reassurance of having strong vendor backing.

JBoss isn't any ordinary J2EE application server either. JBoss has been at the forefront of innovation, pioneering the lightweight microkernel and pluggable services style of development that is popular today. While JBoss can't take sole credit for smart proxies, interceptor stacks, or any of the other technology tracks it is famous for, there's little doubt that JBoss significantly advanced the state of the art and continues to be on the forefront of J2EE.

JBoss isn't just a J2EE server. Most people come to JBoss because they want a J2EE application server, but JBoss's dynamic architecture allows it to go well beyond J2EE. Although JBoss provides a fully certified J2EE container, you are free to alter the services provided to make J2EE work the way you want. You can even throw J2EE away completely, working at a lower services level or at a higher level using technologies such as AOP and Hibernate. You can make JBoss as heavy or as light as you need it to be. You can stick to the J2EE specification for maximum portability, or you can rewrite the rules to obtain maximum agility and performance. With JBoss, the choice is yours!

If you think of JBoss as just an ordinary application server, we hope that in reading this book, you'll begin to feel the same sense of excitement we feel about it. We hope you'll see that JBoss isn't a complex product that you curse at under your breath while wishing for a simpler way to get your work done. It is a flexible platform that you can use to simplify your life, leaving you more time to focus on what is really important: your applications.