因为近期提供接口服务项目中要有个需求,所有的操作必须检查一下服务是否可用的动作,所以感觉Aop实现起来特别合适,整理学习一下小实例。
关于spring-Aop原理:http://m.oschina.net/blog/174838这篇文章写的很好。
个人觉着可能上线的时候配置文件更方便一下,所以例子主要是配置文件方式
Demo文件下载地址:
http://download.csdn.net/detail/ruishenh/7261121
Spring配置文件
/idle-service-impl/src/main/resources/spring/app-config.xml
<?xml version="1.0"encoding="UTF-8"?> <beansxmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"xmlns:context="http://www.springframework.org/schema/context" xmlns:util="http://www.springframework.org/schema/util" xsi:schemaLocation=" http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-3.2.xsd http://www.springframework.org/schema/aophttp://www.springframework.org/schema/aop/spring-aop-3.2.xsd http://www.springframework.org/schema/txhttp://www.springframework.org/schema/tx/spring-tx-3.2.xsd http://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context-3.2.xsd http://www.springframework.org/schema/utilhttp://www.springframework.org/schema/util/spring-util-3.2.xsd"> <context:component-scanbase-package="com.ruishenh.business.impl" /> <aop:aspectj-autoproxyexpose-proxy="true" proxy-target-class="true"/> <context:annotation-config/> <!-- --> <beanid="springFactoryUtil"class="com.ruishenh.utils.SpringFactoryUtil" /> <!-- --> <importresource="aop-advisor.xml" /> </beans>
导入的aop-advisor.xml文件
/idle-service-impl/src/main/resources/spring/aop-advisor.xml
<?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:tx="http://www.springframework.org/schema/tx"xmlns:context="http://www.springframework.org/schema/context" xmlns:util="http://www.springframework.org/schema/util" xsi:schemaLocation=" http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/aophttp://www.springframework.org/schema/aop/spring-aop-3.1.xsd http://www.springframework.org/schema/txhttp://www.springframework.org/schema/tx/spring-tx-3.1.xsd http://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/utilhttp://www.springframework.org/schema/util/spring-util-3.1.xsd"> <bean id="genericAdvisor" class="com.ruishenh.aop.aspect.advisor.GenericAdvisor"/> <aop:config> <!-- 定义切面 --> <aop:aspect ref="genericAdvisor" order="0"> <!-- 定义连接点 --> <aop:pointcut id="businessService" expression="execution(*com.ruishenh.business.impl..*.*(..))" /> <!-- 定义前置 --> <aop:before method="before" pointcut-ref="businessService"/> <!-- 定义环绕 --> <aop:around method="heartbeat" pointcut-ref="businessService"/> <!-- 定义后置 --> <aop:after method="after" pointcut-ref="businessService"/> <!-- 定义Target处理后普通结果增强 --> <aop:after-returning method="afterReturning" pointcut-ref="businessService" returning="obj"/> <!-- 定义Target处理后异常增强 --> <aop:after-throwing method="handlerException" pointcut-ref="businessService" throwing="e"/> </aop:aspect> </aop:config> </beans>
关于这个类
com.ruishenh.aop.aspect.advisor.GenericAdvisor中方法有
1. before 对应Target执行之前
2. heartbeat这个是环绕的一个方法
3. after 对应target执行之后
4. afterReturning 对应在target处理后结果返回增强处理
5. handlerException 对应在target执行异常时增强处理
/idle-service-impl/src/main/java/com/ruishenh/aop/aspect/advisor/GenericAdvisor.java源码
package com.ruishenh.aop.aspect.advisor; import org.aspectj.lang.JoinPoint; importorg.aspectj.lang.ProceedingJoinPoint; import com.ruishenh.domain.account.AccountBank; public class GenericAdvisor { /** * 对于要增强的方法,执行环绕处理检查心跳是否正常 * @param joinPoint * @return * @throws Throwable */ Objectheartbeat(ProceedingJoinPoint joinPoint) throws Throwable{ // if(checkHeartbeat()) { // // } System.out.println("2joinPoint.Signature.name:"+joinPoint.getSignature().getName()); //记得在调用执行方法的时候异常不要try-catch,要thrwos出去,不然可能事务层没法起效,或者增强异常处理也无法起效 Objectobj=joinPoint.proceed(); //下边的参入参数可以修改,但是类型和方法的个数要和原来一致,不然原方法无法执行 // Objectobj=joinPoint.proceed(joinPoint.getArgs()); //对于返回后对象,有可能要做处理,对返回参数的某一些值处理, //可以通过org.springframework.beans.BeanUtils.copyProperties把一些值赋值 if(obj==null) { returnnew AccountBank(); } returnobj; } /** * 对于要增强的方法,在方法之前执行 * @param joinPoint 连接点信息 */ voidbefore(JoinPoint joinPoint){ Object[] objs=joinPoint.getArgs(); System.out.println("1objs:"+objs[0]); System.out.println("1joinPoint:"+joinPoint); }; /** * 对于要增强的方法,在方法之后执行 * @param joinPoint 连接点信息 */ voidafter(JoinPoint joinPoint){ Object[] objs=joinPoint.getArgs(); System.out.println("4objs:"+objs[0]); System.out.println("4joinPoint:"+joinPoint); }; /** * 对于要增加的方法,方法返回结果后,对结果进行记录或者分析 * 方法 * @param obj target执行后返回的结果 */ voidafterReturning(Object obj){ System.out.println("3obj:"+obj); }; /** * 对于要增强的方法,方法抛出异常后,对异常的增强处理,比如记录异常,或者根据异常分析数据什么的 * @param e target执行后抛出的异常 */ voidhandlerException(Throwable e){ System.out.println("handingException......"); e.printStackTrace(); } booleancheckHeartbeat(){ returntrue; } }
Junit测试
/idle-service-impl/src/test/java/com/ruishenh/business/impl/account/AccountServiceImplTest.java
package com.ruishenh.business.impl.account; import org.junit.Before; import org.junit.Test; import org.junit.runner.RunWith; importorg.springframework.test.context.ContextConfiguration; importorg.springframework.test.context.junit4.SpringJUnit4ClassRunner; importcom.ruishenh.domain.account.AccountBank; importcom.ruishenh.domain.account.AccountBankParam; import com.ruishenh.utils.SpringFactoryUtil; @RunWith(SpringJUnit4ClassRunner.class) @ContextConfiguration(locations={"classpath:/spring/app-config.xml"}) public class AccountServiceImplTest { @Before publicvoid setUp() throws Exception { } @Test publicvoid testStoreIn() throws Exception { AccountServiceImplimpl= SpringFactoryUtil.getBean(AccountServiceImpl.class); AccountBankParamparam= new AccountBankParam(); param.setId(100); AccountBankab=impl.storeIn(param); System.out.println(ab.toString()); } }
执行后输出结果:
1objs:com.ruishenh.domain.account.AccountBankParam@d522de2[id=100,name=<null>,account=<null>]
1joinPoint:execution(AccountBankcom.ruishenh.business.impl.account.AccountServiceImpl.storeIn(AccountBankParam))
2joinPoint.Signature.name:storeIn
==============todo=====================
4objs:com.ruishenh.domain.account.AccountBankParam@d522de2[id=100,name=<null>,account=<null>]
4joinPoint:execution(AccountBankcom.ruishenh.business.impl.account.AccountServiceImpl.storeIn(AccountBankParam))
3obj:com.ruishenh.domain.account.AccountBank@2d397e5c[id=0,name=<null>,account=<null>]
com.ruishenh.domain.account.AccountBank@2d397e5c[id=0,name=<null>,account=<null>]