0809 aop

Posted 2022-06-23 zs0322

aop思想： 横向重复 纵向抽取

连接点：给事务提交的方法

通知/增强：方法执行以前调的方法

目标对象：被代理对象

先导包

 新建 接口  Service 并封装 

package com.oracle.service;

public interface UserService 
    public abstract void get();
    public abstract void update();
    public abstract void insert();
    public abstract void delete();

新建个实现类 UserServiceImp

 

package com.oracle.service;
//定义一个接口并实现
public class UserServiceImp implements UserService
    @Override
    public void get() 
        System.out.println("查询用户");        
    

    @Override
    public void update() 
        System.out.println("修改用户 ");
    

    @Override
    public void insert() 
        System.out.println("新增用户");
    

    @Override
    public void delete() 
        System.out.println("删除用户");
        

 new 一个 通知类 advice ，定义为 MyAdvice

package com.oracle.advice;

import org.aspectj.lang.ProceedingJoinPoint;

//新建通知类
public class MyAdvice 
//    前置通知
    public void before()
        System.out.println("这是前置通知");
    
//    后置通知
    public void afterReturning()
        System.out.println("这是后置通知");
    
//    环绕通知 返回值是个obj类型
    public Object around(ProceedingJoinPoint pjp) throws Throwable
        System.out.println("环绕通知之前调用");
        Object obj=pjp.proceed();
        System.out.println("环绕之后调用");
        return pjp;        
    
//    异常通知
    public void afterException()
        System.out.println("异常后调用 ");
    
//    后置通知(不管是否异常都调用 )
    public void after()
        System.out.println("后置通知目标方法执行后调用");
    

然后将它们联系起来 配置一下applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans" 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-4.2.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd ">
    <!-- 配置注解扫描 -->
    <context:component-scan base-package="com.oracle.pojo"></context:component-scan>
    <bean name="car2" class="com.oracle.pojo.Car"></bean>
    <!-- 配置目标对象 -->
    <bean name="userService" class="com.oracle.service.UserServiceImp"></bean>
    <!-- 配置通知对象 -->
    <bean name="myadvice" class="com.oracle.advice.MyAdvice"></bean>
    <aop:config>
    <!--配置切入点
        public void com.oracle.service.UserServiceImp.save()
        void com.oracle.service.UserServiceImp.save()
        * com.oracle.service.UserServiceImp.save()
        * com.oracle.service.UserServiceImp.*()
        
        * com.oracle.service.*ServiceImp.*(..)
                
      -->
      <aop:pointcut expression="execution(* com.oracle.service.*ServiceImp.*(..))" id="pc"/>
      <aop:aspect ref="myadvice">
              <!--指定名为before的方法作为前置通知  -->
              <aop:before method="before" pointcut-ref="pc"/>
              <!--后置  -->
              <aop:after-returning method="afterReturning" pointcut-ref="pc"/>
              <!--环绕通知  -->
              <aop:around method="around" pointcut-ref="pc"/>
              <!--异常拦截通知  -->
              <aop:after-throwing method="afterException" pointcut-ref="pc"/>
              <!--后置  -->
              <aop:after method="after" pointcut-ref="pc"/>          
      </aop:aspect>
</aop:config>
</beans>

最后建个demo测试

package com.oracle.test;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import com.oracle.service.UserService;
//@表示注解,将约束注解到容器
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class Demo01 
    @Autowired
    private UserService userService;
    @Test
    public void get()
        userService.get();
    

运行结果

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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