对于Spring中AOP的配置,一种方式是基于Schema,也就是在xml文件中进行配置,相关配置项在aop命名空间下定义。以下主要通过代码说明基本配置流程。
(1)定义需要实现的业务接口:
package com.aop.service; public interface MyService { public void sayHello(String word); }
(2)编写实现接口的业务类:
package com.aop.service; public class MyServiceImpl implements MyService { @Override public void sayHello(String word) { System.out.println("Say :" + word); } }
(3)定义切面支持类,包含所需的通知方法:
package com.aop.aspect; import org.aspectj.lang.JoinPoint; public class MyAspect { //前置通知 public void beforeAdvice(JoinPoint joinPoint) { System.out.println("--before advice,参数:" + joinPoint.getArgs()[0]); } //后置最终通知 public void afterFinallyAdvice() { System.out.println("------after finally advice"); } }
(4)beans.xml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"> <!-- 接口实现业务类 --> <bean id="MyService" class="com.aop.service.MyServiceImpl" /> <!-- 切面支持类,包含所需的通知方法 --> <bean id="aspect" class="com.aop.aspect.MyAspect" /> <aop:config> <!-- 切点配置,匹配com.aop.service包及子包下的任何方法执行 --> <aop:pointcut id="pointcut" expression="execution(* com.aop.service..*.*(..))" /> <!-- 切面配置, ref 属性用来引用切面支持类 --> <aop:aspect ref="aspect"> <!-- 前置通知,pointcut-ref 引用切点配置bean,method指定通知方法 --> <aop:before pointcut-ref="pointcut" method="beforeAdvice" /> <aop:after pointcut-ref="pointcut" method="afterFinallyAdvice" /> </aop:aspect> </aop:config> </beans>
(5)测试类:
package com.spring.test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.FileSystemXmlApplicationContext; import com.aop.service.MyService; public class TestAop { public static void main(String[] args) { ApplicationContext context = new FileSystemXmlApplicationContext("aopBeans.xml"); MyService service = (MyService) context.getBean("MyService"); service.sayHello("Spring aop"); } }
(6)输出结果:
--before advice,参数:Spring aop Say :Spring aop ------after finally advice