import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

public abstract class ObservableObject implements Observable {
	private Set<Observer> observers = new HashSet<Observer>();

	@Override
	public void add(Observer o) {
		observers.add(o);	
		o.update(); // as to display current value
	}

	@Override
	public void notifyAllObservers() {
		Iterator<Observer> iter = observers.iterator();
		while (iter.hasNext()) {
			Observer o = iter.next();
			o.update();
		}

		/*
		 Koden over tilsvarer en vanlig for-loekke
		 Skrevet paa denne maaten for aa illustrere bruk av iterator

		 for (Observer o : observers) {
		  	o.update();
		 }
		*/
	}
}