abstract class Door{
public abstract void open();
public abstract void close();
}
interface Alarmable{
void alarm();
}
class SafetyDoor extends Door implements Alarmable{
public void open() {
System.out.println("安全门打开");
}
public void close() {
System.out.println("安全门关闭");
}
public void alarm() {
System.out.println("安全门报警");
}
}
public class testDoor {
public static void main(String[] args) {
// TODO Auto-generated method stub
Door d = new SafetyDoor();
d.open();
}
}