aop注解 事例

spring.xml中aop的配置

   <!--
          aop的配置
       -->
       <aop:config>
           <!--
                切入点表达式
            -->
           <aop:pointcut expression="execution(* cn.itcast.spring.aop.sh.PersonDaoImpl.*(..))" id="perform"/>
           <aop:aspect ref="myTransaction">
           <!--
               <aop:before method="beginTransaction" pointcut-ref="perform"/>
               <aop:after-returning method="commit" pointcut-ref="perform" returning="var"/>
            -->
               <aop:after method="finallyMethod" pointcut-ref="perform"/>
               <aop:after-throwing method="throwingMethod" pointcut-ref="perform" throwing="ex"/>
               <aop:around method="aroundMethod" pointcut-ref="perform"/>
           </aop:aspect>
       </aop:config>

自定义的切面

注解形式的aop 写着 切面上

 package cn.itcast.spring.aop.annotation.sh;

 import org.aspectj.lang.JoinPoint;
 import org.aspectj.lang.ProceedingJoinPoint;
 import org.aspectj.lang.annotation.AfterReturning;
 import org.aspectj.lang.annotation.Aspect;
 import org.aspectj.lang.annotation.Before;
 import org.aspectj.lang.annotation.Pointcut;
 import org.hibernate.Transaction;
 import org.springframework.stereotype.Component;

 /**
  * @Aspect
  * ==
  * <aop:config>
  *      <aop:pointcut
  *         expression=
  *     "execution(* cn.itcast.spring.aop.annotation.sh.PersonDaoImpl.*(..))"
  *     id="aa()"/>
  * </aop:config>
  * @author Think
  *
  */
 @Component("myTransaction")
 @Aspect
 public class MyTransaction extends HibernateUtils{
     private Transaction transaction;

     @Pointcut("execution(* cn.itcast.spring.aop.annotation.sh.PersonDaoImpl.*(..))")
     private void aa(){}//方法签名  返回值必须是void  方法的修饰符最好是private ，aa是随便定义的 做类比

     @Before("aa()")
     public void beginTransaction(JoinPoint joinpoint){
         this.transaction = sessionFactory.getCurrentSession().beginTransaction();
     }

     @AfterReturning(value="aa()",returning="val")
     public void commit(Object val){
         this.transaction.commit();
     }

 }

然后在spring.xml中引入

 <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"
     xmlns:tx="http://www.springframework.org/schema/tx"
     xsi:schemaLocation="http://www.springframework.org/schema/beans
                          http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
                          http://www.springframework.org/schema/context
                          http://www.springframework.org/schema/context/spring-context-3.0.xsd
                          http://www.springframework.org/schema/tx
                          http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
                          http://www.springframework.org/schema/aop
                          http://www.springframework.org/schema/aop/spring-aop-3.0.xsd">

 <!--      扫描注解bean -->
      <context:component-scan base-package="cn.us.aspect"/>
 <!--      开启切面代理 使得spring认识 @Aspect -->
      <aop:aspectj-autoproxy/>