001    /* ===========================================================
002     * JFreeChart : a free chart library for the Java(tm) platform
003     * ===========================================================
004     *
005     * (C) Copyright 2000-2005, 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     * DefaultPieDataset.java
029     * ----------------------
030     * (C) Copyright 2001-2005, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   Sam (oldman);
034     *
035     * $Id: DefaultPieDataset.java,v 1.6.2.2 2005/10/25 21:32:29 mungady Exp $
036     *
037     * Changes
038     * -------
039     * 17-Nov-2001 : Version 1 (DG);
040     * 22-Jan-2002 : Removed legend methods from dataset implementations (DG);
041     * 07-Apr-2002 : Modified implementation to guarantee data sequence to remain 
042     *               in the order categories are added (oldman);
043     * 23-Oct-2002 : Added getCategory(int) method and getItemCount() method, in 
044     *               line with changes to the PieDataset interface (DG);
045     * 04-Feb-2003 : Changed underlying data storage to DefaultKeyedValues (DG);
046     * 04-Mar-2003 : Inserted DefaultKeyedValuesDataset class into hierarchy (DG);
047     * 24-Apr-2003 : Switched places with DefaultKeyedValuesDataset (DG);
048     * 18-Aug-2003 : Implemented Cloneable (DG);
049     * 03-Mar-2005 : Implemented PublicCloneable (DG);
050     * 29-Jun-2005 : Added remove() method (DG);
051     * 
052     */
053    
054    package org.jfree.data.general;
055    
056    import java.io.Serializable;
057    import java.util.Collections;
058    import java.util.List;
059    
060    import org.jfree.data.DefaultKeyedValues;
061    import org.jfree.data.KeyedValues;
062    import org.jfree.data.UnknownKeyException;
063    import org.jfree.util.PublicCloneable;
064    
065    /**
066     * A default implementation of the {@link PieDataset} interface.
067     */
068    public class DefaultPieDataset extends AbstractDataset
069                                   implements PieDataset, 
070                                              Cloneable, PublicCloneable, 
071                                              Serializable {
072    
073        /** For serialization. */
074        private static final long serialVersionUID = 2904745139106540618L;
075        
076        /** Storage for the data. */
077        private DefaultKeyedValues data;
078    
079        /**
080         * Constructs a new dataset, initially empty.
081         */
082        public DefaultPieDataset() {
083            this.data = new DefaultKeyedValues();
084        }
085    
086        /**
087         * Creates a new dataset by copying data from a {@link KeyedValues} 
088         * instance.
089         *
090         * @param data  the data (<code>null</code> not permitted).
091         */
092        public DefaultPieDataset(KeyedValues data) {
093            if (data == null) {
094                throw new IllegalArgumentException("Null 'data' argument.");   
095            }
096            this.data = new DefaultKeyedValues();
097            for (int i = 0; i < data.getItemCount(); i++) {
098                this.data.addValue(data.getKey(i), data.getValue(i));
099            }
100        }
101    
102        /**
103         * Returns the number of items in the dataset.
104         *
105         * @return The item count.
106         */
107        public int getItemCount() {
108            return this.data.getItemCount();
109        }
110    
111        /**
112         * Returns the categories in the dataset.  The returned list is 
113         * unmodifiable.
114         *
115         * @return The categories in the dataset.
116         */
117        public List getKeys() {
118            return Collections.unmodifiableList(this.data.getKeys());
119        }
120    
121        /**
122         * Returns the key for an item.
123         *
124         * @param item  the item index (zero-based).
125         *
126         * @return The key.
127         */
128        public Comparable getKey(int item) {
129            Comparable result = null;
130            if (getItemCount() > item) {
131                result = this.data.getKey(item);
132            }
133            return result;
134        }
135    
136        /**
137         * Returns the index for a key.
138         *
139         * @param key  the key.
140         *
141         * @return The index, or <code>-1</code> if the key is unrecognised.
142         */
143        public int getIndex(Comparable key) {
144            return this.data.getIndex(key);
145        }
146    
147        /**
148         * Returns a value.
149         *
150         * @param item  the value index.
151         *
152         * @return The value (possibly <code>null</code>).
153         */
154        public Number getValue(int item) {
155    
156            Number result = null;
157            if (getItemCount() > item) {
158                result = this.data.getValue(item);
159            }
160            return result;
161    
162        }
163    
164        /**
165         * Returns the data value associated with a key.
166         *
167         * @param key  the key (<code>null</code> not permitted).
168         *
169         * @return The value (possibly <code>null</code>).
170         * 
171         * @throws UnknownKeyException if the key is not recognised.
172         */
173        public Number getValue(Comparable key) {
174            if (key == null) {
175                throw new IllegalArgumentException("Null 'key' argument.");
176            }
177            return this.data.getValue(key);
178        }
179    
180        /**
181         * Sets the data value for a key.
182         *
183         * @param key  the key.
184         * @param value  the value.
185         */
186        public void setValue(Comparable key, Number value) {
187            this.data.setValue(key, value);
188            fireDatasetChanged();
189        }
190    
191        /**
192         * Sets the data value for a key.
193         *
194         * @param key  the key.
195         * @param value  the value.
196         */
197        public void setValue(Comparable key, double value) {
198            setValue(key, new Double(value));
199        }
200        
201        /**
202         * Removes an item from the dataset and sends a {@link DatasetChangeEvent}
203         * to all registered listeners.
204         * 
205         * @param key  the key.
206         */
207        public void remove(Comparable key) {
208            this.data.removeValue(key);   
209            fireDatasetChanged();
210        }
211    
212        /**
213         * Tests if this object is equal to another.
214         *
215         * @param obj  the other object.
216         *
217         * @return A boolean.
218         */
219        public boolean equals(Object obj) {
220            if (obj == this) {
221                return true;
222            }
223    
224            if (!(obj instanceof PieDataset)) {
225                return false;
226            }
227            PieDataset that = (PieDataset) obj;
228            int count = getItemCount();
229            if (that.getItemCount() != count) {
230                return false;
231            }
232    
233            for (int i = 0; i < count; i++) {
234                Comparable k1 = getKey(i);
235                Comparable k2 = that.getKey(i);
236                if (!k1.equals(k2)) {
237                    return false;
238                }
239    
240                Number v1 = getValue(i);
241                Number v2 = that.getValue(i);
242                if (v1 == null) {
243                    if (v2 != null) {
244                        return false;
245                    }
246                }
247                else {
248                    if (!v1.equals(v2)) {
249                        return false;
250                    }
251                }
252            }
253            return true;
254    
255        }
256    
257        /**
258         * Returns a hash code.
259         * 
260         * @return A hash code.
261         */
262        public int hashCode() {
263            return this.data.hashCode();
264        }
265    
266        /**
267         * Returns a clone of the dataset.
268         * 
269         * @return A clone.
270         * 
271         * @throws CloneNotSupportedException This class will not throw this 
272         *         exception, but subclasses (if any) might.
273         */
274        public Object clone() throws CloneNotSupportedException {
275            DefaultPieDataset clone = (DefaultPieDataset) super.clone();
276            clone.data = (DefaultKeyedValues) this.data.clone();
277            return clone;    
278        }
279        
280    }