多态-接口回调Demo

class zhu {
public static void main(String[] args) {
Connect c = new JDBC();//创建对象时使用接口的上转型
c.add(user);
c.delete(user);
}
}
interface Connect{//接口
public static void add(User user);
public static void delete(User user);
}
class JDBC implements Connect{
void open(User user){}
void close(User user){}
}
class H implements Connect{
void open(User user){}
void close(User user){}
}

class zhu {
public static void main(String[] args) {
MainBorad mb = new MainBorad();
mb.add(new NetCard());
}
}

class MianBorad{
public void run(){
System.out.pritfln("MainBoard run");
}
public void add(PIC p){
p.open();
p.close();
}
}
interface PIC{
public static void open();
public static void close();
}
class NetCard implements PIC{
public void open(){

}
public void close(){

}
}
class VoiceCard implements PIC{
public void open(){

}
public void close(){

}
}