/*

* (3) Following the example in Transmogrify.java, create a Starship class

* containing an AlertStatus reference that can indicate three different states.

* Include methods to change the states.

*/

class AlertStatus {

public void alert() {}

}

class NormalStatus extends AlertStatus {

@Override

public void alert() { System.out.println("Normal"); }

}

class AlarmStatus extends AlertStatus {

@Override

public void alert() { System.out.println("Alarm"); }

}

class DangerStatus extends AlertStatus {

@Override

public void alert() { System.out.println("Danger"); }

}

class Starship {

private AlertStatus alertStatus = new NormalStatus();

public void changeStatus(AlertStatus status) { alertStatus = status; }

public void performAlert() { alertStatus.alert(); }

}

public class App {

public static void main(String[] args) {

Starship ship = new Starship();

ship.performAlert();

ship.changeStatus(new AlarmStatus());

ship.performAlert();

ship.changeStatus(new DangerStatus());

ship.performAlert();

}

}