@Aspect

作用是标记一个切面类（spring不会将切面注册为Bean也不会增强，但是需要扫描）

<!-- 扫描Aspect增强的类 -->
<context:component-scan base-package="">
    <context:include-filter type="annotation"
        expression="org.aspectj.lang.annotation.Aspect"/>
</context:component-scan>
<!-- 开启@AspectJ注解支持 -->
<aop:aspectj-autoproxy/>
<?xml version="1.0" encoding="UTF-8"?>
  <beans xmlns="http://www.springframework.org/schema/beans"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
         xmlns:context="http://www.springframework.org/schema/context"
         xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
    <!--包扫描-->    <context:component-scan base-package="com.cn"/>
    <!--开启ioc注解-->
    <context:annotation-config/>
    <!--开启aop注解-->
    <aop:aspectj-autoproxy/>
 </beans>