Dynamic Weaving AOP Technology Based On CAR

In complicated application system, there are some common behaviors among many unrelated program modules, It's the so called "crosscutting concerns". The feature of these crosscutting concerns(such as log,transactional management,, performance optimization, exception handling and design mode, etc)is that they all scattered in many of the system's core functional modules. Because these concern's implementation have to be interweaved in different matter field's code, it lead to the result that their implement are either scattering(one concern's implementation scattered in many place of system)or tangling(one program module describes the implementation of more than one concerns). And it's hard to implement these crosscutting concerns with clear, modularized code either in POP or OOP.Aspect-oriented-programming (AOP) model can automatically weave these crosscutting concerns into the Object-oriented software system, and implement the modulization of crosscutting concerns. Aspect is the core of AOP, it means to modularize a concern that may crosscut in many program modules, these modularized concerns calls "Aspect". Besides helping us resolve the problems of code scattering and tangling, AOP also brings us many other goods: (1) Easier system extending. Because Aspect can let programmer get to multi-interface of many functions, so it's easy for us to add new aspect in order to extending the former function. (2) Easier upgrade. Using AOP, designer can postpone their decision for the future requirements; just implement the urgent needs, and using Aspect to coupling the new needs with the previous needs when needed in the future. (3) Better code reuse. The ultimate aim of every new programming technology is all the same: code reuse. AOP implemented every Aspect as an independent module, every module is loose coupled, it's more understandable and easy to maintain, it also has less code redundancy, and more reusable.But AOP is not always superior to OOP, especially in some occasions that there are few crosscutting relationships among objects. So AOP is the supplement of OOP in some application occasion. We can say that AOP is the improvement of OOP by means of implement loose coupling of program modules,enhance software's...