001    /*****************************************************************************
002     * Copyright (C) PicoContainer Organization. All rights reserved.            *
003     * ------------------------------------------------------------------------- *
004     * The software in this package is published under the terms of the BSD      *
005     * style license a copy of which has been included with this distribution in *
006     * the LICENSE.txt file.                                                     *
007     *                                                                           *
008     * Original code by                                                          *
009     *****************************************************************************/
010    package org.picocontainer.gems.monitors.prefuse;
011    
012    import java.util.HashSet;
013    import java.util.Set;
014    
015    import org.picocontainer.gems.monitors.ComponentDependencyMonitor.Dependency;
016    
017    /**
018     * Understands non-duplicated dependencies.
019     * 
020     * @author Peter Barry
021     * @author Kent R. Spillner
022     */
023    public final class DependencySet implements ComponentDependencyListener {
024    
025        private final Set uniqueDependencies = new HashSet();
026    
027        private final ComponentDependencyListener listener;
028    
029        public DependencySet(final ComponentDependencyListener listener) {
030            this.listener = listener;
031        }
032    
033        public void addDependency(final Dependency dependency) {
034            if (uniqueDependencies.add(dependency)) {
035                listener.addDependency(dependency);
036            }
037        }
038    
039        public Dependency[] getDependencies() {
040            return (Dependency[]) uniqueDependencies.toArray(new Dependency[uniqueDependencies.size()]);
041        }
042    }