package bean;

public interface CD {
    void play();
}

package bean;

import org.springframework.stereotype.Component;

@Component// 该注解表示该类是一个组件类，并且spring会为这个类创建一个bean
public class CD1 implements CD {

    @Override
    public void play() {
        System.out.println("我是CD1");
    }

}

package bean;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

@Component("cdPlayer")   //声明这个类为组件类，spring会为这个类创建一个bean，这个bean的id为“cdPlayer”
public class CDPlayer {

    private CD cd;

    @Autowired   //自动装配注解，spring会自动注入一个CD类
    public CDPlayer(CD cd) {
        this.cd = cd;
    }

    public void play() {

        cd.play();
    }

}

package test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

import bean.CDConfig;
import bean.CDPlayer;

public class Test {
    public static void main(String[] args) {
        
        ApplicationContext context=new AnnotationConfigApplicationContext(CDConfig.class);
        CDPlayer cdplayer=(CDPlayer)context.getBean("cdPlayer");
        cdplayer.play(); 
    }
}