在Spring中如何使用动态代理?

package com.lxc.diy;

import org.aspectj.lang.annotation.After;

import org.aspectj.lang.annotation.Aspect;

import org.aspectj.lang.annotation.Before;

/**

  * @Aspect 标注这个了是一个切面

  * @Before("切入点") === <aop:before method="beforeLog" pointcut-ref="point" />

  * @After("切入点") === <aop:after method="afterLog" pointcut-ref="point" />

  */

@Aspect

public class diyNotePoint {

    @Before ( "execution(* com.lxc.service.UserServiceImp.*(..))" )

    public void before() {

        System.out.println( "前置切面" );

    }

    @After ( "execution(* com.lxc.service.UserServiceImp.*(..))" )

    public void after() {

        System.out.println( "后置切面" );

    }

}

package com.lxc.service;

public interface UserService {

     public void query();

     public void delete();

     public void edit();

     public void add();

}

package com.lxc.service;

public class UserServiceImp implements UserService{

     @Override

     public void query() {

         System.out.println( "query" );

     }

     @Override

     public void delete() {

         System.out.println( "delete" );

     }

     @Override

     public void edit() {

         System.out.println( "edit" );

     }

     @Override

     public void add() {

         System.out.println( "add" );

     }

}

<?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"

        xmlns:context= "http://www.springframework.org/schema/context"

        xsi:schemaLocation="http: //www.springframework.org/schema/beans

         https: //www.springframework.org/schema/beans/spring-beans.xsd

         http: //www.springframework.org/schema/context

         https: //www.springframework.org/schema/context/spring-context.xsd

         http: //www.springframework.org/schema/aop

         https: //www.springframework.org/schema/aop/spring-aop.xsd">

     <!--定义bean-->

     <bean id= "imp" class = "com.lxc.service.UserServiceImp" />

     <bean id= "diyNotePoint" class = "com.lxc.diy.diyNotePoint" />

     <!--添加：注解支持-->

     <aop:aspectj-autoproxy />

</beans>

import com.lxc.service.UserService;

import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Test {

     public static void main(String[] args) {

         ApplicationContext ctx = new ClassPathXmlApplicationContext( "beans.xml" );

         UserService userService = ctx.getBean( "imp" , UserService. class );

         userService.add();

     }

}