001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2008, by Object Refinery Limited and Contributors.
006 *
007 * Project Info:  http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
022 * USA.
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
025 * in the United States and other countries.]
026 *
027 * -----------------------------
028 * StandardEntityCollection.java
029 * -----------------------------
030 * (C) Copyright 2001-2008, by Object Refinery Limited.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * Changes
036 * -------
037 * 23-May-2002 : Version 1 (DG);
038 * 26-Jun-2002 : Added iterator() method (DG);
039 * 03-Oct-2002 : Fixed errors reported by Checkstyle (DG);
040 * 19-May-2004 : Implemented Serializable (DG);
041 * 29-Sep-2004 : Renamed addEntity() --> add() and addEntities()
042 *               --> addAll() (DG);
043 * 19-Jan-2005 : Changed storage from Collection --> List (DG);
044 * 20-May-2005 : Fixed bug 1113521 - inefficiency in getEntity() method (DG);
045 * ------------- JFREECHART 1.0.x ---------------------------------------------
046 * 01-Dec-2006 : Implemented PublicCloneable and fixed clone() method (DG);
047 *
048 */
049
050package org.jfree.chart.entity;
051
052import java.io.Serializable;
053import java.util.Collection;
054import java.util.Collections;
055import java.util.Iterator;
056import java.util.List;
057
058import org.jfree.util.ObjectUtilities;
059import org.jfree.util.PublicCloneable;
060
061/**
062 * A standard implementation of the {@link EntityCollection} interface.
063 */
064public class StandardEntityCollection implements EntityCollection,
065        Cloneable, PublicCloneable, Serializable {
066
067    /** For serialization. */
068    private static final long serialVersionUID = 5384773031184897047L;
069
070    /** Storage for the entities. */
071    private List entities;
072
073    /**
074     * Constructs a new entity collection (initially empty).
075     */
076    public StandardEntityCollection() {
077        this.entities = new java.util.ArrayList();
078    }
079
080    /**
081     * Returns the number of entities in the collection.
082     *
083     * @return The entity count.
084     */
085    public int getEntityCount() {
086        return this.entities.size();
087    }
088
089    /**
090     * Returns a chart entity from the collection.
091     *
092     * @param index  the entity index.
093     *
094     * @return The entity.
095     *
096     * @see #add(ChartEntity)
097     */
098    public ChartEntity getEntity(int index) {
099        return (ChartEntity) this.entities.get(index);
100    }
101
102    /**
103     * Clears all the entities from the collection.
104     */
105    public void clear() {
106        this.entities.clear();
107    }
108
109    /**
110     * Adds an entity to the collection.
111     *
112     * @param entity  the entity (<code>null</code> not permitted).
113     */
114    public void add(ChartEntity entity) {
115        if (entity == null) {
116            throw new IllegalArgumentException("Null 'entity' argument.");
117        }
118        this.entities.add(entity);
119    }
120
121    /**
122     * Adds all the entities from the specified collection.
123     *
124     * @param collection  the collection of entities (<code>null</code> not
125     *     permitted).
126     */
127    public void addAll(EntityCollection collection) {
128        this.entities.addAll(collection.getEntities());
129    }
130
131    /**
132     * Returns the last entity in the list with an area that encloses the
133     * specified coordinates, or <code>null</code> if there is no such entity.
134     *
135     * @param x  the x coordinate.
136     * @param y  the y coordinate.
137     *
138     * @return The entity (possibly <code>null</code>).
139     */
140    public ChartEntity getEntity(double x, double y) {
141        int entityCount = this.entities.size();
142        for (int i = entityCount - 1; i >= 0; i--) {
143            ChartEntity entity = (ChartEntity) this.entities.get(i);
144            if (entity.getArea().contains(x, y)) {
145                return entity;
146            }
147        }
148        return null;
149    }
150
151    /**
152     * Returns the entities in an unmodifiable collection.
153     *
154     * @return The entities.
155     */
156    public Collection getEntities() {
157        return Collections.unmodifiableCollection(this.entities);
158    }
159
160    /**
161     * Returns an iterator for the entities in the collection.
162     *
163     * @return An iterator.
164     */
165    public Iterator iterator() {
166        return this.entities.iterator();
167    }
168
169    /**
170     * Tests this object for equality with an arbitrary object.
171     *
172     * @param obj  the object to test against (<code>null</code> permitted).
173     *
174     * @return A boolean.
175     */
176    public boolean equals(Object obj) {
177        if (obj == this) {
178            return true;
179        }
180        if (obj instanceof StandardEntityCollection) {
181            StandardEntityCollection that = (StandardEntityCollection) obj;
182            return ObjectUtilities.equal(this.entities, that.entities);
183        }
184        return false;
185    }
186
187    /**
188     * Returns a clone of this entity collection.
189     *
190     * @return A clone.
191     *
192     * @throws CloneNotSupportedException if the object cannot be cloned.
193     */
194    public Object clone() throws CloneNotSupportedException {
195        StandardEntityCollection clone
196                = (StandardEntityCollection) super.clone();
197        clone.entities = new java.util.ArrayList(this.entities.size());
198        for (int i = 0; i < this.entities.size(); i++) {
199            ChartEntity entity = (ChartEntity) this.entities.get(i);
200            clone.entities.add(entity.clone());
201        }
202        return clone;
203    }
204
205}