AOP浅谈

直接实践，概念查看相关资料

1.切面=切点（应用的地址）+通知（做什么）

2.AOP个人理解就是在某件事件之前或之后，应该做些什么？

举个例子：比如我们在跑步之前，你需要做热身运动，运动之后需要做拉伸运动。

package com.jack.begin.chatpter1.aop;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class Run {

Logger logger = LoggerFactory.getLogger(Run.class);

public void run(){
logger.info("开始跑步了");
}
}

3.接着你需要做热身运动和拉伸运动

package com.jack.begin.chatpter1.aop;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class WarmUp {

Logger logger = LoggerFactory.getLogger(WarmUp.class);
public void before(){
logger.info("开始热身了");
}

public void after(){
logger.info("跑步做拉伸运动");
}
}

4.关键切面的配置

<?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:p="http://www.springframework.org/schema/p"
xmlns:c="http://www.springframework.org/schema/c"
xmlns:util="http://www.springframework.org/schema/util"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:ehcache="http://www.springmodules.org/schema/ehcache"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.1.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.1.xsd http://www.springmodules.org/schema/ehcache http://www.springmodules.org/schema/cache/springmodules-ehcache.xsd"> <bean id="warmUp" class="com.jack.begin.chatpter1.aop.WarmUp"></bean>
<!-- runs不能和切点名称一致 -->
<bean id="runs" class="com.jack.begin.chatpter1.aop.Run"></bean>
<aop:config>
<aop:aspect ref="warmUp">

<!-- 这里是配置切点，做某件事情（这里是跑步）-->
<aop:pointcut expression="execution(* *.run(..)))" id="run"/>

<!--这里是通知，也就是跑步之前需要做热身运动-->
<aop:before method="before"
pointcut-ref="run"/>

<!--这里是通知，也就是跑步之后需要做拉伸运动-->

<aop:after method="after"pointcut-ref="run"/></aop:aspect></aop:config></beans>

5.测试

package com.jack.begin.chatpter1;

import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.jack.begin.chatpter1.aop.Index;
import com.jack.begin.chatpter1.aop.Run;

public class ChapterTest {

@Test
public void RunAop(){
ApplicationContext context = new ClassPathXmlApplicationContext("spring/chapter1/aop.xml");
Run run = (Run) context.getBean("runs");
run.run();
}
}

6.效果

5.当然这里是理解aop思想，大量用于日志和事务当中，可以这个理解日志在调用这个方法时之前或之后需要记录操作情况