AspectJ框架基于注解的AOP实现

 1 package com.sjl.aspectj.annotation; 2 ?3 import org.aspectj.lang.JoinPoint; 4 import org.aspectj.lang.ProceedingJoinPoint; 5 import org.aspectj.lang.annotation.*; 6 import org.springframework.stereotype.Component; 7 ?8 /** 9 ?* 切面类，在此类中编写通知10 ?* */11 @Aspect12 @Component //这个注解的作用是实例化对象，相当于在配置文件中<bean id="" class="">13 public class MyAspect {14 ????//定义切入点表达式15 ????@Pointcut("execution(* com.sjl.jdk.*.*(..))")16 ????//用一个返回值为void、方法体为空的方法来命名切入点17 ????private void myPoint(){ }18 19 ????// 前置通知20 ????@Before("myPoint()")21 ????public void myBefore(JoinPoint joinPoint) {22 ????????System.out.print("前置通知 ：模拟执行权限检查...,");23 ????????System.out.print("目标类是："+joinPoint.getTarget().getClass() );24 ????????System.out.println(",被织入增强处理的目标方法为："25 ????????????????+joinPoint.getSignature().getName());26 ????}27 28 ????// 后置通知29 ????@AfterReturning("myPoint()")30 ????public void myAfterReturning(JoinPoint joinPoint) {31 ????????System.out.print("后置通知：模拟记录日志...," );32 ????????System.out.println("被织入增强处理的目标方法为："33 ????????????????+ joinPoint.getSignature().getName());34 ????}35 36 ????/**37 ?????* 环绕通知38 ?????* ProceedingJoinPoint 是JoinPoint子接口，表示可以执行目标方法39 ?????* 1.必须是Object类型的返回值40 ?????* 2.必须接收一个参数，类型为ProceedingJoinPoint41 ?????* 3.必须throws Throwable42 ?????*/43 ????@Around("myPoint()")44 ????public Object myAround(ProceedingJoinPoint proceedingJoinPoint)45 ????????????throws Throwable {46 ????????// 开始47 ????????System.out.println("环绕开始：执行目标方法之前，模拟开启事务...");48 ????????// 执行当前目标方法49 ????????Object obj = proceedingJoinPoint.proceed();50 ????????// 结束51 ????????System.out.println("环绕结束：执行目标方法之后，模拟关闭事务...");52 ????????return obj;53 ????}54 55 ????// 异常通知56 ????@AfterThrowing(value = "myPoint()",throwing = "e")57 ????public void myAfterThrowing(JoinPoint joinPoint, Throwable e) {58 ????????System.out.println("异常通知：" + "出错了" + e.getMessage());59 ????}60 61 ????// 最终通知62 ????@After("myPoint()")63 ????public void myAfter() {64 ????????System.out.println("最终通知：模拟方法结束后的释放资源...");65 ????}66 }67 /**68 ?* 提醒：同时记得jdk包下的目标类也要进行一个持久化层的一个注解的添加；69 ?* */

package com.sjl.jdk;public interface UserDao { ????void addUser(); ????void deleteUser();}

package com.sjl.jdk;import org.springframework.stereotype.Repository;/** * UserDaoImpl是目标类，对其中的方法进行增强处理； */@Repository("userDao")public class UserDaoImpl implements UserDao{ ???@Override ???public void addUser() { ???????System.out.println("添加用户"); ???} ???@Override ???public void deleteUser() { ???????System.out.println("删除用户"); ???}}

<?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-4.3.xsd ???????http://www.springframework.org/schema/context ???????http://www.springframework.org/schema/context/spring-context-4.3.xsd ???????http://www.springframework.org/schema/aop ???????http://www.springframework.org/schema/aop/spring-aop.xsd"> ???<!--指定需要扫描的包，使注解生效--> ???<context:component-scan base-package="com.sjl"/> ???<!--启动注解声明式AspectJ支持--> ???<aop:aspectj-autoproxy /></beans>

package com.sjl.aspectj.annotation;import com.sjl.jdk.UserDao;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;//测试类public class TestAnnotationAspectj { ???public static void main(String[] args) { ???????String xmlPath="applicationContext02Annotation.xml"; ???????ApplicationContext ac=new ClassPathXmlApplicationContext(xmlPath);
 ???????//接口类型，向上造型 ?提高代码的复用性，其实也可以强转为父类，就强转为子类，
 ???????// 但是复用性就差，因为后面如果还有其它的代码就不利于使用
 ???????UserDao userDao=(UserDao)ac.getBean("userDao"); userDao.addUser();
 ???}
 }