The main way to achive AOP is deploying a xml file。
Now a xml file is presented to be a explanation .
<?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:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd"> <context:annotation-config /> <context:component-scan base-package="com.bjsxt"/> <bean id="logInterceptor" class ="com.bjsxt.aop.LogInterceptor"></bean> <aop:config> <aop:pointcut expression="execution(public * com.bjsxt.service..*.add(..))" id="servicePointcut"/> <aop:aspect id="logAspect" ref="logInterceptor"> <aop:before method="before" pointcut-ref="servicePointcut" /> </aop:aspect> </aop:config> </beans>
The tag <aop:config> declares that we will deploy a aop now.
While,I declare a "pointcut" at first. It is obvIoUs that it's a globe pointcut and it works for every aspect behind it .
"expression="execution(public * com.bjsxt.service..*.add(..))" shows the pointcut represent all method like “add()” in the classes of the package named"com.bjsxt.service.."
the pointcut‘s id is “servicePointcut” in addition。
Next, a aspect is declared whose name is “logAspect” 。 (nobody care what name it has in this situation)。
pointcut-ref="servicePointcut" shows that it is a aspect for the pointcut named “servicePointcut”which we had created a moment ago.
Its ref = <span style="font-family: Arial,Helvetica,sans-serif;">"logInterceptor" ,so we can find a bean named logInterceptor to know what methods the aspect has。And according to the sentence “<aop:before method</span>
<span style="font-family: Arial,sans-serif;">="before" ",I think we must do the method named "before" in "logIntercepor " as the type of" before method". It means the method woulb be done before pointcut.</span>
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<span style="font-family: Arial,sans-serif;">We can also complete the xml file in design mode。 It looks much more clear.</span>
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