achieve aop through xml

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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, Helvetica, 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, Helvetica, sans-serif;">We can also complete the xml file in design mode。 It looks much more clear.</span>
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