aspectj aop 切面与切点

可以在方法加入 joinPoint 获取切点信息

切面：

@Aspect

public class AopAspectJ

{

// 前置通知：方法执行之前获得增强

@Before ( value = "savePoint()" )

public void beforAop ( JoinPoint joinPoint )

{

System . out . println ( "this is before aop and joinPoint : " + joinPoint ) ;

}

// 后置通知：可以获取方法返回值， result 的名字可以任意取名，但是需要和方法对应

@AfterReturning ( value = "execution(* com.imooc.service.TestService.update())" , returning = "result" )

public void afterReturningAop ( Object result )

{

System . out . println ( "This is after retruning aop and result :" + result ) ;

}

// 环绕通知：如果不调用 joinPoint.proceed(); 则目标方法不会执行

@Around ( value = "execution(* com.imooc.service.TestService.delete(..))" )

public Object aroundAop ( ProceedingJoinPoint joinPoint ) throws Throwable

{

System . out . println ( "This is around aop --- before" ) ;

Object proceed = joinPoint . proceed () ;

System . out . println ( "This is around aop --- after" ) ;

return proceed ;

}

// 异常抛出通知：可以获取异常属性

@AfterThrowing ( value = "execution(* com.imooc.service.TestService.wrong(..))" , throwing = "e" )

public void throwAop ( Exception e )

{

System . out . println ( "this is throw Aop and e : " + e ) ;

}

// 最终通知：总是会被执行 ( 即使发生异常 ) ，相当于 fianally

@After ( value = "execution(* com.imooc.service.TestService.*(..))" )

public void afterAop ()

{

System . out . println ( "This is after aop ,the last advice" ) ;

}

// 切点： public void 无参方法，方法名为切点 使用 @Pointcut 进行定义。若存在多个切点，可以使用 || 分隔

@Pointcut ( value = "execution(* com.imooc.service.TestService.save(..)) || execution(* com.imooc.service.TestService.update())" )

private void savePoint ()

{

}

}

切点：

public class TestServiceImpl implements TestService

{

@Override

public void save ()

{

System . out . println ( "This is save method" ) ;

}

}

测试类：

@RunWith ( SpringJUnit4ClassRunner . class )

@ContextConfiguration ( "classpath:applicationContext.xml" )

public class DemoTest

{

@Resource

private TestService testService ;

@Test

public void demo ()

{

testService . save () ;

getPrintln () ;

testService . update () ;

getPrintln () ;

testService . delete () ;

getPrintln () ;

testService . wrong () ;

}

private void getPrintln ()

{

System . out . println ( "---------------------" ) ;

}

}

// 切面写完了之后需要到xml对bean进行定义

<? 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.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-3.0.xsd" >

< aop :aspectj-autoproxy />

< context :component-scan base-package ="com.imooc" />

<!-- 切面需要申明 -->

< bean class ="com.imooc.aop.AopAspectJ" />

</ beans >

下面给出XML的配置方法：

使用xml后，切面类不需要注解

< context :component-scan base-package ="com.imooc.xmlaspectj" />

< bean id ="AopAspectJWithXml" class ="com.imooc.xmlaspectj.aopwithxml.AopAspectJWithXml" />

<!--xml 配置 -->

< aop :config >

<!-- 切点 -->

< aop :pointcut id ="TestWithXmlService"

expression ="execution(* com.imooc.xmlaspectj.servicewithxml.TestWithXmlService.save())" />

<!-- 切面 -->

< aop :aspect ref ="AopAspectJWithXml" >

< aop :before method ="beforAop" pointcut-ref ="TestWithXmlService" />

< aop :after-returning method ="afterReturningAop" pointcut-ref ="TestWithXmlService" returning ="result" />

</ aop :aspect >

</ aop :config >

poml.xml

< dependencies >

< dependency >

< groupId > junit </ groupId >

< artifactId > junit </ artifactId >

< version > 4.12 </ version >

</ dependency >

<!-- 引入 Spring 的基本开发包 -->

< dependency >

< groupId > org.springframework </ groupId >

< artifactId > spring-core </ artifactId >

< version > 4.2.4.RELEASE </ version >

</ dependency >

< dependency >

< groupId > org.springframework </ groupId >

< artifactId > spring-context </ artifactId >

< version > 4.2.4.RELEASE </ version >

</ dependency >

< dependency >

< groupId > org.springframework </ groupId >

< artifactId > spring-beans </ artifactId >

< version > 4.2.4.RELEASE </ version >

</ dependency >

< dependency >

< groupId > org.springframework </ groupId >

< artifactId > spring-expression </ artifactId >

< version > 4.2.4.RELEASE </ version >

</ dependency >

< dependency >

< groupId > aopalliance </ groupId >

< artifactId > aopalliance </ artifactId >

< version > 1.0 </ version >

</ dependency >

< dependency >

< groupId > org.springframework </ groupId >

< artifactId > spring-aop </ artifactId >

< version > 4.2.4.RELEASE </ version >

</ dependency >

< dependency >

< groupId > org.aspectj </ groupId >

< artifactId > aspectjweaver </ artifactId >

< version > 1.8.9 </ version >

</ dependency >

< dependency >

< groupId > org.springframework </ groupId >

< artifactId > spring-aspects </ artifactId >

< version > 4.2.4.RELEASE </ version >

</ dependency >

< dependency >

< groupId > org.springframework </ groupId >

< artifactId > spring-test </ artifactId >

< version > 4.2.4.RELEASE </ version >

</ dependency >

</ dependencies >