001    /*
002    @license.text@
003     */
004    package biz.hammurapi.util;
005    
006    /**
007     * Classes which want broadcast changes in them 
008     * should implement this interface.
009     * @author Pavel Vlasov
010     * @revision $Revision$
011     */
012    public interface Observable {
013            
014            /**
015             * Adds observer to a collection of observers.
016             * @param observer
017             */
018        void addObserver(Observer observer);
019        
020        /**
021         * Removes observer from observers collection.
022         * @param observer
023         */
024        void removeObserver(Observer observer);
025    }