1. 概念
Aspect-Oriented Programming (AOP)可以说是OOP(Object Oriented Programming，面向对象编程)的补充和完善。
OOP引入封装、继承、多态等概念来建立一种对象层次结构，用于模拟公共行为的一个集合。不过OOP允许开发者定义纵向的关系，但并不适合定义横向的关系，例如日志功能。
AOP技术恰恰相反，它利用一种称为"横切"的技术，剖解开封装的对象内部，并将那些影响了多个类的公共行为封装到一个可重用模块，并将其命名为"Aspect"，即切面。
2. AOP核心概念
- Aspect（切面）
- Join point
- Advice
- Pointcut
- Introduction
- Target object
- AOP proxy
- Weaving
3. Spring对AOP的支持
3.1示例
<!--AOP begin-->
<aop:aspectj-autoproxy proxy-target-class="true"/>
<bean id="testAspect" class="com.xxxx.fabu.aspect.TestAspect"/>
<!--要求进入到AOP的配置，重点配置切入点，以及确定切入的处理操作方法-->
<aop:config>
<aop:pointcut id="pointCut" expression="execution(* com.xxxx.fabu.service..*.*(..)) and args(id)"/>
<aop:aspect ref="testAspect"><!--进行切面的配置，如果是切面控制应该有一个控制的类-->
<aop:before method="beforeMethod" pointcut-ref="pointCut" arg-names="id"/>
<aop:after method="afterMethod" pointcut="execution(* com.xxxx.fabu.service..*.*(..))"/>
</aop:aspect>
</aop:config>
<!--AOP end-->
3.2 其他示例
- the execution of any public method:
execution(public * *(..))
- the execution of any method with a name beginning with "set":
execution(* set*(..))
- the execution of any method defined by the AccountService interface:
execution(* com.xyz.service.AccountService.*(..))
- the execution of any method defined in the service package:
execution(* com.xyz.service.*.*(..))
- the execution of any method defined in the service package or a sub-package:
execution(* com.xyz.service..*.*(..))
- any join point (method execution only in Spring AOP) within the service package:
within(com.xyz.service.*)
- any join point (method execution only in Spring AOP) within the service package or a sub-package:
within(com.xyz.service..*)
- any join point (method execution only in Spring AOP) where the proxy implements the AccountService interface:
this(com.xyz.service.AccountService)
