一、SpringAop的具体实现

首先准备好jar包

1.aopalliance-1.0.jar

2.aspectjrt-1.9.4.jar

3.aspectjweaver-1.9.4.jar

4.spring-aop.jar

步骤

1. 创建切面类/通知类LogBefore并且实现接口MethodBeforeAdvice重写该接口的before方法

   package edu.gdkm.aop;
   import org.springframework.aop.MethodBeforeAdvice;
   import java.lang.reflect.Method;
   //前置通知
   public class LogBefore implements MethodBeforeAdvice {
       @Override
       public void before(Method method, Object[] objects, Object o) throws Throwable {
           System.out.println("xml形式前置通知"+o+method.getName()+objects.length);
       }
   }
   

2. 创建业务类、业务方法

   package edu.gdkm.dao;
   public interface UserDao {   //UserDao接口
       void test();
   }
   

   package edu.gdkm.dao.impl;
   import edu.gdkm.dao.UserDao;
   public class UserDaoImpl implements UserDao {    //UserDaoImpl实现类
       @Override
       public void test() {
           System.out.println("test方法");
       }
   }

3. 创建applicationContext.xml配置文件编写增强类与切面类的配置

<?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-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">
    
    <!--切面类-->
    <bean id="logBefore" class="edu.gdkm.aop.LogBefore"></bean>
    <!--增强类-->
    <bean id="userDao" class="edu.gdkm.dao.impl.UserDaoImpl"></bean>
    <!--把线LogBefore与UserDaoImpl两端连接起来-->
    <aop:config>
        <!--定义切入点-->
        <aop:pointcut id="pointcut" expression="execution( public void edu.gdkm.dao.impl.UserDaoImpl.test() )"  />
        <!--advice-ref：具体的通知     pointcut-ref:哪个切入点-->
        <aop:advisor advice-ref="logBefore" pointcut-ref="pointcut"/>
    </aop:config>

</beans>

4. 创建测试类jdkTest

package edu.gdkm.test;

import edu.gdkm.dao.UserDao;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class jdkTest {
    public static void main(String[] args) {
        ApplicationContext act = new ClassPathXmlApplicationContext("applicationContext.xml");
        UserDao userDao = (UserDao) act.getBean("userDao");
        userDao.test();
    }
}

二、基于注解的形式实现

步骤

1.创建切面类

package edu.gdkm.aop;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.*;
import org.springframework.stereotype.Component;

import java.util.Arrays;

@Component("logAnnotation")
@Aspect
public class LogAspectAnnotation {

    //前置通知
    @Before("execution(public * test(..))")
    public void myBefore(JoinPoint point){
        System.out.println("注解形式前置通知"+point.getTarget()+point.getSignature().getName()+ Arrays.toString(point.getArgs()));
    }
    //后置通知
    @AfterReturning(pointcut="execution(public * test(..))",returning = "returningValue")
    public void myAfterReturning(JoinPoint point,Object returningValue){
        System.out.println("注解形式后置通知"+point.getTarget().toString()+point.getSignature().getName()+returningValue);
    }

    //环绕通知
    @Around("execution(public * test(..))")
    public void myAround(ProceedingJoinPoint joinPoint){
        try{
            System.out.println("环绕前置通知");
            joinPoint.proceed();
            System.out.println("环绕后置通知");
        }catch (Throwable t){
            System.out.println("环绕异常通知");
        }finally {
            System.out.println("环绕最终通知");
        }
    }

    //异常通知
    @AfterThrowing("execution(public * test(..))")
    public void myException (){
        System.out.println("注解形式异常通知");
    }

    //最终通知
    @After("execution(public * test(..))")
    public void myAfter(){
        System.out.println("注解形式最终通知");
    }
}

2.在spring配置文件开启自动代理配置

<aop:aspectj-autoproxy></aop:aspectj-autoproxy>
<context:component-scan base-package="edu.gdkm.aop"></context:component-scan>