Spring学习(21)--- AOP之Advice应用(上)
前置通知(Before advice) | 在某个连接点(join point)之前执行的通知,但不能阻止连接点前的执行(除非它抛出异常) |
返回后通知(After returning advice) | 在某个连接点(join point)正常完成后执行的通知 |
抛出异常后通知(After throwing advice) | 在方法抛出异常退出时执行的通知 |
后通知(After(finally) advice) | 当某个连接点退出的时候执行的通知(无论是正常返回还是异常退出) |
环绕通知(Around advice) | 包围一个连接点(join point)的通知 |
导入需要的包:aspectjweaver.jar、aopalliance-1.0.jar
(一)Before Advice
例子:
新建两个类:
package com.aop.schema;
/**
*
* 切面类
*
*/
public class MyAspect { public void before(){
System.out.println("MyAspect.before");
}
}
package com.aop.schema;
/**
*
* 业务类
*
*/
public class ApsectBiz { public void biz(){
System.out.println("ApsectBiz.biz");
}
}
XML配置:
<?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"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.1.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-4.1.xsd"> <bean id="myAspect" class="com.aop.schema.MyAspect"></bean> <bean id="apsectBiz" class="com.aop.schema.ApsectBiz"></bean> <aop:config>
<aop:aspect id="myAspectAOP" ref="myAspect">
<aop:pointcut id="myPointcut" expression="execution(* com.aop.schema.ApsectBiz.*(..))" />
<aop:before method="before" pointcut-ref="myPointcut"/>
</aop:aspect>
</aop:config> </beans>
单元测试:
package com.aop.schema; import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext; public class UnitTest { @Test
public void test(){
ApplicationContext context = new ClassPathXmlApplicationContext("classpath:spring-aop.xml");
ApsectBiz biz = (ApsectBiz)context.getBean("apsectBiz");
biz.biz();
}
}
结果:
七月 09, 2015 10:30:24 下午 org.springframework.context.support.AbstractApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@31b3c607: startup date [Thu Jul 09 22:30:24 CST 2015]; root of context hierarchy
七月 09, 2015 10:30:24 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [spring-aop.xml]
MyAspect.before
ApsectBiz.biz
PS:ApsectBiz.biz是业务方法,在它之前,执行了前置通知MyAspect.before,符合想要的结果
(二)After returning advice
例子:
修改一下切面类MyAspect(添加afterreturning方法):
package com.aop.schema;
/**
*
* 切面类
*
*/
public class MyAspect { public void before(){
System.out.println("MyAspect.before");
} public void afterreturning(){
System.out.println("MyAspect.afterreturning");
}
}
XML配置修改为:
<?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"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.1.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-4.1.xsd"> <bean id="myAspect" class="com.aop.schema.MyAspect"></bean> <bean id="apsectBiz" class="com.aop.schema.ApsectBiz"></bean> <aop:config>
<aop:aspect id="myAspectAOP" ref="myAspect">
<aop:pointcut id="myPointcut" expression="execution(* com.aop.schema.ApsectBiz.*(..))" />
<aop:before method="before" pointcut-ref="myPointcut"/>
<aop:after-returning method="afterreturning" pointcut-ref="myPointcut"/>
</aop:aspect>
</aop:config> </beans>
单元测试同上:
结果:
七月 09, 2015 10:38:41 下午 org.springframework.context.support.AbstractApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@31b3c607: startup date [Thu Jul 09 22:38:41 CST 2015]; root of context hierarchy
七月 09, 2015 10:38:41 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [spring-aop.xml]
MyAspect.before
ApsectBiz.biz
MyAspect.afterreturning
(三)After throwing advice
说明:使用throwing属性来指定可被传递的异常的参数名称
例子:
修改一下切面类MyAspect(添加afterthrowing方法):
package com.aop.schema;
/**
*
* 切面类
*
*/
public class MyAspect { public void before(){
System.out.println("MyAspect.before");
} public void afterreturning(){
System.out.println("MyAspect.afterreturning");
} public void afterthrowing(){
System.out.println("MyAspect.afterthrowing");
}
}
修改业务类ApsectBiz(抛出一个异常):
package com.aop.schema; /**
*
* 业务类
*
*/
public class ApsectBiz { public void biz(){
System.out.println("ApsectBiz.biz");
throw new RuntimeException(); //故意抛出异常
}
}
XML配置:
<?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"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.1.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-4.1.xsd"> <bean id="myAspect" class="com.aop.schema.MyAspect"></bean> <bean id="apsectBiz" class="com.aop.schema.ApsectBiz"></bean> <aop:config>
<aop:aspect id="myAspectAOP" ref="myAspect">
<aop:pointcut id="myPointcut" expression="execution(* com.aop.schema.ApsectBiz.*(..))" />
<aop:before method="before" pointcut-ref="myPointcut"/>
<aop:after-returning method="afterreturning" pointcut-ref="myPointcut"/>
<aop:after-throwing method="afterthrowing" pointcut-ref="myPointcut"/>
</aop:aspect>
</aop:config> </beans>
单元测试同上:
测试结果:
七月 09, 2015 10:47:46 下午 org.springframework.context.support.AbstractApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@31b3c607: startup date [Thu Jul 09 22:47:46 CST 2015]; root of context hierarchy
七月 09, 2015 10:47:46 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [spring-aop.xml]
MyAspect.before
ApsectBiz.biz
MyAspect.afterthrowing
PS:有没有发现有什么问题? MyAspect.afterreturning没有了,biz()中抛出异常,biz()方法没有正常返回,所以MyAspect.afterreturning没有了。
(四)After(finally) advice
修改一下切面类MyAspect(添加after方法):
package com.aop.schema;
/**
*
* 切面类
*
*/
public class MyAspect { public void before(){
System.out.println("MyAspect.before");
} public void afterreturning(){
System.out.println("MyAspect.afterreturning");
} public void afterthrowing(){
System.out.println("MyAspect.afterthrowing");
} public void after(){
System.out.println("MyAspect.after");
}
}
XML配置:
<?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"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.1.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-4.1.xsd"> <bean id="myAspect" class="com.aop.schema.MyAspect"></bean> <bean id="apsectBiz" class="com.aop.schema.ApsectBiz"></bean> <aop:config>
<aop:aspect id="myAspectAOP" ref="myAspect">
<aop:pointcut id="myPointcut" expression="execution(* com.aop.schema.ApsectBiz.*(..))" />
<aop:before method="before" pointcut-ref="myPointcut"/>
<aop:after-returning method="afterreturning" pointcut-ref="myPointcut"/>
<aop:after-throwing method="afterthrowing" pointcut-ref="myPointcut"/>
<aop:after method="after" pointcut-ref="myPointcut"/>
</aop:aspect>
</aop:config> </beans>
单元测试同上:
结果:
七月 09, 2015 10:56:10 下午 org.springframework.context.support.AbstractApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@31b3c607: startup date [Thu Jul 09 22:56:10 CST 2015]; root of context hierarchy
七月 09, 2015 10:56:10 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [spring-aop.xml]
MyAspect.before
ApsectBiz.biz
MyAspect.afterthrowing
MyAspect.after
(五)Around advice
注意:通知方法的第一个参数必ProceedingJoinPoint类型
例子:
修改一下切面类MyAspect(添加around方法):
package com.aop.schema; import org.aspectj.lang.ProceedingJoinPoint; /**
*
* 切面类
*
*/
public class MyAspect { public void before(){
System.out.println("MyAspect.before");
} public void afterreturning(){
System.out.println("MyAspect.afterreturning");
} public void afterthrowing(){
System.out.println("MyAspect.afterthrowing");
} public void after(){
System.out.println("MyAspect.after");
} public void around(ProceedingJoinPoint pjp) throws Throwable{
System.out.println("MyAspect.around_1");
Object obj=pjp.proceed();
System.out.println("MyAspect.around_2");
}
}
XML配置:
<?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"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.1.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-4.1.xsd"> <bean id="myAspect" class="com.aop.schema.MyAspect"></bean> <bean id="apsectBiz" class="com.aop.schema.ApsectBiz"></bean> <aop:config>
<aop:aspect id="myAspectAOP" ref="myAspect">
<aop:pointcut id="myPointcut" expression="execution(* com.aop.schema.ApsectBiz.*(..))" />
<aop:before method="before" pointcut-ref="myPointcut"/>
<aop:after-returning method="afterreturning" pointcut-ref="myPointcut"/>
<aop:after-throwing method="afterthrowing" pointcut-ref="myPointcut"/>
<aop:after method="after" pointcut-ref="myPointcut"/>
<aop:around method="around" pointcut-ref="myPointcut"/>
</aop:aspect>
</aop:config> </beans>
单元测试同上:
结果:
七月 09, 2015 11:15:20 下午 org.springframework.context.support.AbstractApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@31b3c607: startup date [Thu Jul 09 23:15:20 CST 2015]; root of context hierarchy
七月 09, 2015 11:15:20 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [spring-aop.xml]
MyAspect.before
MyAspect.around_1
ApsectBiz.biz
java.lang.RuntimeException
at com.aop.schema.ApsectBiz.biz(ApsectBiz.java:11)
at com.aop.schema.ApsectBiz$$FastClassBySpringCGLIB$$ae10254d.invoke(<generated>)
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:717)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:85)
at com.aop.schema.MyAspect.around(MyAspect.java:31)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:621)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:610)
at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:68)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.aspectj.AspectJAfterAdvice.invoke(AspectJAfterAdvice.java:43)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.aspectj.AspectJAfterThrowingAdvice.invoke(AspectJAfterThrowingAdvice.java:58)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.adapter.AfterReturningAdviceInterceptor.invoke(AfterReturningAdviceInterceptor.java:52)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:52)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:653)
at com.aop.schema.ApsectBiz$$EnhancerBySpringCGLIB$$1fbf7bae.biz(<generated>)
at com.aop.schema.UnitTest.test(UnitTest.java:13)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)
MyAspect.after
MyAspect.afterreturning
PS:有异常,仔细看,原来是around(ProceedingJoinPoint pjp)的try catch捕捉到了biz()抛出的异常,现在把异常注释掉(try catch里面怎么处理异常?这里要看具体的业务需要,这里先注释掉)
package com.aop.schema;
/**
*
* 业务类
*
*/
public class ApsectBiz { public void biz(){
System.out.println("ApsectBiz.biz");
//throw new RuntimeException(); //故意抛出异常
}
}
测试结果:
七月 09, 2015 11:18:17 下午 org.springframework.context.support.AbstractApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@31b3c607: startup date [Thu Jul 09 23:18:17 CST 2015]; root of context hierarchy
七月 09, 2015 11:18:17 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [spring-aop.xml]
MyAspect.before
MyAspect.around_1
ApsectBiz.biz
MyAspect.around_2
MyAspect.after
MyAspect.afterreturning
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