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• IUserService

package com.qfedu.aop07;import java.util.List;/** * Created by HuangCong on 2020/2/26. */public interface IUserService {       List

• UserServiceImpl实现类：

package com.qfedu.aop07;import org.springframework.stereotype.Component;import java.util.List;/** * Created by HuangCong on 2020/2/26. */@Component("us")public class UserServiceImpl implements IUserService {       @Override    public List

• MyAspect：切面类

package com.qfedu.aop07;/** * Created by HuangCong on 2020/2/28. */public class MyAspect {       public void before() {           System.out.println("=========Before=========");    }    public void after() {           System.out.println("=========After==========");    }}

• UserServiceImpl2

package com.qfedu.aop07;import org.springframework.stereotype.Component;import java.util.ArrayList;import java.util.List;@Component("us2")public class UserServiceImpl2 implements IUserService {       @Override    public List

• MyBeanPostProcessor类

package com.qfedu.aop07;import org.springframework.beans.BeansException;import org.springframework.beans.factory.config.BeanPostProcessor;import org.springframework.cglib.proxy.InvocationHandler;import org.springframework.cglib.proxy.Proxy;import org.springframework.lang.Nullable;import java.lang.reflect.Method;/** * 配置了包扫描之后，该类会初始化两个对象EventListenerMethodProcessor和DefaultEventListenerFactory，再外加我们自己的组件对象 * 所以会发现有一个before和一个after打印 * 我还专门加了一个UserServiceImpl2，你会发现将有二个before和二个after的打印（注意看看该类上的Component注解是否启用） */public class MyBeanPostProcessor implements BeanPostProcessor {       @Nullable    @Override    public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {           System.out.println("=======Before======" + bean);        return bean;    }    @Nullable    @Override    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {           System.out.println("========After======" + bean);        return Proxy.newProxyInstance(MyBeanPostProcessor.class.getClassLoader(), bean.getClass().getInterfaces(), new InvocationHandler() {               @Override            public Object invoke(Object o, Method method, Object[] objects) throws Throwable {                   MyAspect ma = new MyAspect();                ma.before();                Object obj = method.invoke(bean, objects);                ma.after();                return obj;            }        });    }}

• beans_aop07.xml:XML文件配置

• TestAOP07

package com.qfedu.aop07;import org.junit.Test;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;/** * Created by HuangCong on 2020/2/28. */public class TestAOP07 {       @Test    public void testAOP06() {           ApplicationContext context = new ClassPathXmlApplicationContext("beans_aop07.xml");        IUserService us = context.getBean("us", IUserService.class);        Object obj = new Object();        us.getAllUser();        us.saveUser(obj);        us.deleteUser(1);        us.updateUser(obj);    }}