Introduction

You've already seen how AspectJ can provide enhancements to existing object-oriented design patterns in Chapter 17 through Chapter 19. This books finishes by giving you an overview of some of the emerging best practices in AspectJ software development by focusing on some of the new aspect-oriented design patterns and how those patterns are implemented using AspectJ.

Aspect-oriented design patterns are common, best practice aspect-oriented solutions to common aspect-oriented design problems. AspectJ idioms are common uses of the AspectJ language syntax and tool usage. Although aspect-orientation is a fairly new discipline and AspectJ an even younger implementation of that discipline, the active AspectJ community has discovered some design patterns and idioms.

As adoption of the aspect-oriented approach continues to increase in momentum, new best practices will be discovered and captured as design patterns. In time these discoveries could lead to as rich and useful a collection of patterns as those that the object-oriented development community enjoys.

For more information and examples of AspectJ language and tool usage idioms check out Ron Bodkin's work on the aTrack project , which has a wealth of reusable aspect and pointcut libraries, available at http://atrack.dev.java.net Check out Mik Kersten's standard pointcut idioms, which are available by going to http://www.eclipse.org/aspectj and clicking on Documentation standard pointcut idioms. These two experts have provided some of the pioneering work on AspectJ language and tool idioms.