package observer1;

import java.util.List;
import java.util.Observable;
import java.util.Observer;

/**
 * Implementation eines Observers.
 * 
 * @author  Ralf Kunze (rkunze@uos.de), Institut fuer Informatik, Universitaet Osnabrueck
 * @date 15.06.2007
 */
public class MultiplizierObserver implements Observer {

    private int result;
    
    /* (non-Javadoc)
     * @see java.util.Observer#update(java.util.Observable, java.lang.Object)
     */
    public void update(Observable o, Object arg) {
        if(arg instanceof List) {
            List l = (List)arg;
            result = 1;
            for(Object object: l) {
                if(object instanceof Integer) {
                    result *= (Integer)object;
                }
            }
            System.out.println("Neues Multiplikationsergebnis = " + result);
        }
    }

}