| This book is about component-based development on the server. Examples
for such technologies are Enterprise JavaBeans (EJB), CORBA
Components (CCM) or Microsoft’s COM+, which have all gained
widespread use recently. To build successful applications based on
these technologies, the developer should have an understanding of the
workings of such a component architecture – things the specification
and most books don’t talk about very much. Part I of this book contains
a pattern language that describes these architectures conceptually. To
provide ‘grounding in the real world’, Part II contains extensive examples
of these patterns using the EJB technology. Lastly, Part III shows
the benefits of the patterns for a real application.
Distributed components, and specifically EJB, are ‘complex technologies
with a friendly face’. This means that a lot of the complexity is
hidden behind simple interfaces or implemented with wizards et
cetera. However, to create efficient and maintainable applications
based on these technologies, we think it is necessary to understand how
these architectures actually work and how some specific design techniques
must be used. These techniques are very different from object
orientation – trying to use OO techniques for components can result in
very inefficient systems.
This book consists of three separate parts. Part I is intended for developers
or architects who want to learn about the basic principles and
concepts used in any of the mainstream component technologies. We
use the form of a pattern language for this task. Because each pattern
comprises a short example in EJB, CCM and COM+, you can also use
this section to understand the differences between these technologies. |
