001    /*
002    @license.text@
003     */
004    package biz.hammurapi.util;
005    
006    /**
007     * Observer of observable
008     * @author Pavel Vlasov
009     * @revision $Revision$
010     */
011    public interface Observer {
012            
013            /**
014             * Callback method.
015             * @param observable Observable
016             * @param arg Additional argument describing type of change.
017             */
018        void update(Observable observable, Object arg);
019    }