Spring之AOP实现面向切面编程

Posted 2020-09-19 zsychanpin

近期在学Java的动态代理和Spring面向切面编程，越来越认为Spring设计的真的是太完美了。于是，想一个最简单的样例来跑一下。但问题多多，显示缺少，Aspectj里面的相应的类。导入Aspectj.jar呗。可是装Aspectj.jar跟一般的导入.jar不一样，还须要安装并改动Path变量，加入安装文件夹下的bin文件夹到PATH中，并将安装文件夹下lib文件夹里的.jar文件导入MyEclipse。然后，又出现了NoSuchMethodError: net.sf.cglib.proxy.Enhancer.setInterceptDuringConstruction(Z)V错误。于是又找cglib.jar包，导入.jar包，依旧是相同的错误。搜了搜。原来是应该导入cglib-nodep-2.1_3.jar而不是cglib2.jar，导入完毕，问题解决。bravo！

//AOPTest.java

package com.spring.aop;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class AOPTest {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		ApplicationContext ctx=new ClassPathXmlApplicationContext("aop.xml");
		Consume consume=(Consume)ctx.getBean("consume");
		consume.consumeService();
	}

}

//Consume.java

package com.spring.aop;

public class Consume {
	public void consumeService()
	{
		System.out.println("The food is delicious!");
	}
}	

//Service.java

package com.spring.aop;

public class Service {
	public void beforConsume()
	{
		System.out.println("Before consume!");
	}
	public void afterConsume()
	{
		System.out.println("After consume!");
	}
}

//配置文件

<?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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-3.0.xsd">
	<bean name="service" class="com.spring.aop.Service"/>
	<bean name="consume" class="com.spring.aop.Consume"/>
	<aop:config>
		<aop:aspect ref="service">
			<aop:pointcut id="consumeService" expression="execution(* *.consumeService(..))" />
			<aop:before pointcut-ref="consumeService" method="beforConsume"/>
			<aop:after pointcut-ref="consumeService" method="afterConsume"/>
		</aop:aspect>
	</aop:config>
</beans>

//程序依赖包和结果