1.創建一個接口USB
public interface USB {
void open();
void close();
}
2.創建一個類UPan實現接口USB
public class UPan implements USB{
public void open(){
System.out.println("upan open");
}
public void close(){
System.out.println("upan close");
}
}
3.使用Upan
public class BookPC {
public static void main(String[] args) {
useUSB(new UPan());
}
public static void useUSB(USB u){
u.open();
u.close();
}
}