spring AOP的学习

@autor:韩克 2019-07-19 21:09:44

方式一：使用bean生成Proxy的方式（jdk动态代理方式）

1. 创建目标类接口

使用bean生成Proxy的方式底层使用的是jdk动态代理，所以需要创建接口。

public interface EmployeeService {
    public void dosome();
}

2.创建目标类，实现相应的接口

public class EmployeeServiceImpl implements EmployeeService{

@Override
public void dosome() {
    System.out.println("员工工作中....");        
}

@Override
public void playGame() {
    System.out.println("趁老板不在，玩会游戏...");
}
    
}

3.创建通知类，实现相应的接口，在重写方法中写相应的通知。

前置通知：implements MethodBeforeAdvice

package com.xt.advice;

import java.lang.reflect.Method;

import org.springframework.aop.MethodBeforeAdvice;

public class EmpBeforeAdvice implements MethodBeforeAdvice{
    @Override
    public void before(Method arg0, Object[] arg1, Object arg2) throws Throwable {

        System.out.println("记录员工行为....");
        
    }

}

后置通知：implements AfterReturningAdvice

package com.xt.advice;

import java.lang.reflect.Method;

import org.springframework.aop.AfterReturningAdvice;

public class EmpAfterAdvice implements AfterReturningAdvice{

    @Override
    public void afterReturning(Object arg0, Method arg1, Object[] arg2, Object arg3) throws Throwable {
        
        System.out.println("摄像头已记录用户行为...");
        
    }
    
}

4.配置applicationContext.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans 
        http://www.springframework.org/schema/beans/spring-beans.xsd">
    <bean id="empAfterAdvice" class="com.xt.advice.EmpAfterAdvice"></bean>
    <bean id="empBeforeAdvice" class="com.xt.advice.EmpBeforeAdvice"></bean>
    <bean id="employeeServiceImpl" class="com.xt.service.impl.EmployeeServiceImpl"></bean>
    <bean id="regExpAfterAdvice" class="org.springframework.aop.support.RegexpMethodPointcutAdvisor">
        <property name="patterns">
            <list>
                <value>.*dosome.*</value>
            </list>
        </property>
        <property name="advice" ref="empAfterAdvice"></property>
    </bean>
    <bean id="regExpBeforeAdvice" class="org.springframework.aop.support.RegexpMethodPointcutAdvisor">
        <property name="patterns" value=".*dosome.*"></property>
        <property name="advice" ref="empBeforeAdvice"></property>
    </bean>
    <bean id="empProxy" class="org.springframework.aop.framework.ProxyFactoryBean">
        <property name="target" ref="employeeServiceImpl"></property>
        <property name="interfaces" value="com.xt.service.EmployeeService"></property>
        <property name="interceptorNames">
            <list>
                <value>regExpAfterAdvice</value> 
                <value>regExpBeforeAdvice</value> 
            </list>
        </property>
    </bean> 
</beans>

方式二：AspectJ注解方式（通过cglib动态代理实现）

一、创建目标对象,在目标对象中不需要使用任何注解。

package com.xt.pojo;

public class Tauren {
    public void buyHP(){
        System.out.println("战士买HP");
    }
    
    public void buyMP() {
        System.out.println("战士买MP");
    }
    
    public void combat() {
        System.out.println("斗牛士在战斗");
    }
}

二、创建切面

package com.xt.advice;

import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
/* @Aspect:用来声明切面，写在通知类 */
@Aspect
public class Shop {
    //前置增强 
    /* 注意括号的匹配，execution不要写错！ */
    @Before("execution(* com.xt.pojo.Tauren.buy*(..))")
    public void buybefore(){
        System.out.println("玩家进入商店！");
    }
    //后置增强
    @After("execution(* com.xt.pojo.Tauren.buy*(..))")
    public void buyAfter(){
        System.out.println("药水添加到背包！");
    }
}

三、在applicationContext.xml中注册目标和切面

<?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"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd">

    <!-- 注册目标类 -->
    <bean id="tauren" class="com.xt.pojo.Tauren"></bean>
    <!-- 注册切面 -->
    <bean id="shop" class="com.xt.advice.Shop"></bean>
    <!-- 注册自动代理 -->
    <aop:aspectj-autoproxy></aop:aspectj-autoproxy>
    
</beans>

四、测试

package com.xt.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.xt.pojo.Tauren;

public class Test {
    @org.junit.Test
    public void test() {
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");       
        Tauren tauren = (Tauren) applicationContext.getBean("tauren",Tauren.class);//注意使用目标类
        tauren.buyHP();
        tauren.buyMP();
        tauren.combat();
    }
}