Aspect Oriented Programming's Application In UP

In the past several years, a new programming idea was put forward after Procedural-Oriented Programming and Object-Oriented Programming. And it was appraised as one of the ten technologies which has the greatest impact on the economy and the human being's living and working in the 21st century by <>.Aspect oriented programming uses aspect to abstract the cross-cutting concerns, and implements the aspects separately, so as to avoid the problems of code tangling and code scattering caused by object-oriented paradigm. Aspect-oriented paradigm complements object-oriented paradigm well, not only because AO forwards concept of systematically abstracting and modularizing cross-cutting concerns, which smoothes the transition from modeling to implementation, but AOP also brings new factors to the Design Pattern and Use Case Drven of object-oriented paradigm.This article mainly introduce the origin of AOP, the core idea of AOP which include some primary and basic concept and the two crosscutting method. Then some popular AOP tools are introduced and compared. What is important is analysing how to use AOP in a real system through an example. What we use is the essence of AOP which can extract the crosscutting concern of system and make it as the individual module of system. Then we can solve the problem which OOP can't figure out. In this way, we can be absorbed in implementing the core business logic and the code redundancy and coupling will be improved. Thus, our system will be more extendable,reusable and easy to maintain.At last, the unified process is introduced. AOP and unified process are combinedthrough practice. We can see the value of AOP from higher view.