package clock; import java.util.*; public class ClockTimer extends Observable { List observers; public int getHour() { return 0; } public int getMinute() { return 0; } public int getSeconds() { return 0; } public void addObserver(Object observer) { this.observers.add(observer); } public void tick() { this.notifyObservers(); } public ClockTimer() { super(); { this.observers = new ArrayList(); } } }