spring详解（三）——AOP

AOP： 注解来完成

1、加入依赖的jar文件

2、创建一个切面类

package com.zhiyou.zjc.aspect;

import java.util.Arrays;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.springframework.stereotype.Component;
import org.springframework.stereotype.Controller;

@Component
@Aspect
public class CountAspect {    
    @Before("execution(* com.zhiyou.zjc.aspect.CountDaoImp.*(..))")
    public void logbefore(JoinPoint joinPoint) {
        Object[] args = joinPoint.getArgs();
        System.out.println("==========before=========="+joinPoint.getSignature().getName()+Arrays.asList(args));
    }
    @After("execution(* com.zhiyou.zjc.aspect.CountDaoImp.*(..))")
    public void logafter() {
        System.out.println("=====after=======");
    }
    
}

3、在spring配置文件中开启切面注解

<context:component-scan base-package="com.zhiyou.zjc.aspect"></context:component-scan>
<aop:aspectj-autoproxy/>

4、测试

package com.zhiyou.zjc.aspect;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Test {
    public static void main(String[] args) {
        ApplicationContext app = new ClassPathXmlApplicationContext("spring.xml");
        CountDao coImp = (CountDao) app.getBean("imp2");
        coImp.add(2, 3);
    }  
    
}

AOP：基于xml的方式

<?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.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.2.xsd">
    <!-- 定义被通知的程序类 -->
    <bean id="imp2" class="com.zhiyou.zjc.aspect.CountDaoImp2"></bean>
    <!-- 定义切面类的bean -->
    <bean id="aspect" class="com.zhiyou.zjc.aspect.CountAspect2" />
    
    <!-- 配置切面的xml文件 -->
    <aop:config>
        <!-- 定义表达式切点 -->
        <aop:pointcut expression="execution(* com.zhiyou.zjc.aspect.*.*(..))" id="pointcut"/>    
        <!-- 定义切面 -->    
        <aop:aspect id="lodaspect" ref="aspect">
            <!-- 定义前置通知 -->
            <aop:before method="logbefore" pointcut-ref="pointcut"/>
            <!-- 定义后置通知 -->
            <aop:after method="logafter" pointcut-ref="pointcut"/>
        </aop:aspect>
        
        
    </aop:config>
</beans>