// **********************************************************************// // <copyright>// //  BBN Technologies//  10 Moulton Street//  Cambridge, MA 02138//  (617) 873-8000// //  Copyright (C) BBNT Solutions LLC. All rights reserved.// // </copyright>// **********************************************************************// // $Source: /cvs/distapps/openmap/src/openmap/com/bbn/openmap/proj/ProjectionStackSupport.java,v $// $RCSfile: ProjectionStackSupport.java,v $// $Revision: 1.3.2.1 $// $Date: 2004/10/14 18:27:38 $// $Author: dietrick $// // **********************************************************************package com.bbn.openmap.proj;import com.bbn.openmap.util.Debug;import java.util.ArrayList;import java.util.Iterator;/** * This is a utility class that can be used by beans that need support * for handling ProjectionListeners and firing ProjectionEvents. You * can use an instance of this class as a member field of your bean * and delegate work to it. */public class ProjectionStackSupport implements java.io.Serializable {    transient private ArrayList triggers;    /**     * Construct a ProjectionStackSupport.     */    public ProjectionStackSupport() {}    /**     * Add a ProjectionStackTrigger.     *      * @param pt ProjectionStackTrigger     */    public synchronized void add(ProjectionStackTrigger pt) {        if (triggers == null) {            triggers = new ArrayList();        }        if (!triggers.contains(pt)) {            triggers.add(pt);        }    }    /**     * Remove a ProjectionStackTrigger.     *      * @param pt ProjectionStackTrigger     */    public synchronized void remove(ProjectionStackTrigger pt) {        if (triggers == null) {            return;        }        triggers.remove(pt);    }    /**     * Return a cloned list of Triggers.     *      * @return Vector of triggers, null if none have been added.     */    public synchronized ArrayList getTriggers() {        if (triggers == null) {            return null;        }        return (ArrayList) triggers.clone();    }    public int size() {        return triggers.size();    }    /**     * Send a status to all registered triggers.     *      * @param enableBackProjections there is at least one past     *        projection in the back cache.     * @param enableForwardProjections there is at least one future     *        projection in the forward cache. Used when a past     *        projection is being used.     */    public void fireStackStatus(boolean enableBackProjections,                                boolean enableForwardProjections) {        ProjectionStackTrigger target;        ArrayList targets = getTriggers();        if (triggers == null) {            return;        }        Iterator iterator = targets.iterator();        while (iterator.hasNext()) {            target = (ProjectionStackTrigger) iterator.next();            if (Debug.debugging("projectionstack")) {                Debug.output("ProjectionStackSupport.fireStackStatus(): target is: "                        + target);            }            target.updateProjectionStackStatus(enableBackProjections,                    enableForwardProjections);        }    }}