AspectJ Cookbook

Chapter 1. Aspect Orientation Overview

This chapter gives a brief overview of aspect orientation. What is discussed here is by no means a definitive description of aspect-oriented concepts, but it should present a flavor of these concepts and the related terminology. This provides a reference that will prove useful as you implement the practical recipes throughout the rest of the book.

A Brief History of Aspect Orientation

Aspect orientation is not a completely new approach to writing software. In much the same way as virtual machine systems were not an entirely new concept when Java became recognized and adopted by the software community, there have been tools and development environments for some time that support some of the capabilities that are now being placed under the banner of aspect orientation. Like Java, aspect orientation is becoming a commonly adopted and de facto approach to practicing older ideas that can be traced to almost the beginning of software development.

Development environments and tools that weave code, pragma instructions, and even debuggers all contain some of the behavior that underlies the aspect-oriented approach. But the significant difference is in the philosophy behind the approach and how that philosophy drives the technology and tools. Aspect orientation is not about any one of these technologies on its own, though it is a new and more modular implementation of the advantages that these technologies have brought to their own domains in the past. ...