Day11多态部分-5

package Day11;


public class Test_05 {


	public static void main(String[] args) {
		MainBoard mb = new MainBoard();
		mb.run();
 //		mb.useNetCard( );
//		mb.useSoundCard( );
		mb.useNetCard(new NetCard());//没必要创建引用了
		mb.useSoundCard(new soundCard());
	}
}
interface PCI {
	public void open();


	public void close();
}


class NetCard implements PCI {
	public void open() {
		System.out.println("启动网卡");
	}


	public void close() {
		System.out.println("关闭网卡");
	}
}


class soundCard implements PCI {
	public void open() {
		System.out.println("关闭声卡");
	}


	public void close() {
		System.out.println("关闭声卡");
	}
}


class MainBoard {
	public void run() {
		System.out.println("启动主板");
	}


	public void useNetCard(NetCard n) {//引用子类的方法
		n.open();
		n.close();
	}


	public void useSoundCard(soundCard n) {//引用
		n.open();
		n.close();
	}
	//接口型引用,指向自己的子类对象,接口不能创建对象,只能用子类
	public void usePCI(PCI p) {//PCI p= new NetCard()....
		if (p != null) {//如果有什么传入进来就显示什么
			p.open();
			p.close();
		}
	}
}