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 * CategoryToPieDataset.java
029 * -------------------------
030 * (C) Copyright 2003-2008, by Object Refinery Limited.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   Christian W. Zuckschwerdt;
034 *
035 * Changes
036 * -------
037 * 23-Jan-2003 : Version 1 (DG);
038 * 30-Jul-2003 : Pass through DatasetChangeEvent (CZ);
039 * 29-Jan-2004 : Replaced 'extract' int with TableOrder (DG);
040 * 11-Jan-2005 : Removed deprecated code in preparation for the 1.0.0
041 *               release (DG);
042 * ------------- JFREECHART 1.0.0 RELEASED ------------------------------------
043 * 26-Jul-2006 : Added serialVersionUID, changed constructor to allow null
044 *               for source, and added getSource(), getExtractType() and
045 *               getExtractIndex() methods - see feature request 1477915 (DG);
046 *
047 */
048
049package org.jfree.data.category;
050
051import java.util.Collections;
052import java.util.List;
053
054import org.jfree.data.general.AbstractDataset;
055import org.jfree.data.general.DatasetChangeEvent;
056import org.jfree.data.general.DatasetChangeListener;
057import org.jfree.data.general.PieDataset;
058import org.jfree.util.TableOrder;
059
060/**
061 * A {@link PieDataset} implementation that obtains its data from one row or
062 * column of a {@link CategoryDataset}.
063 */
064public class CategoryToPieDataset extends AbstractDataset
065        implements PieDataset, DatasetChangeListener {
066
067    /** For serialization. */
068    static final long serialVersionUID = 5516396319762189617L;
069
070    /** The source. */
071    private CategoryDataset source;
072
073    /** The extract type. */
074    private TableOrder extract;
075
076    /** The row or column index. */
077    private int index;
078
079    /**
080     * An adaptor class that converts any {@link CategoryDataset} into a
081     * {@link PieDataset}, by taking the values from a single row or column.
082     * <p>
083     * If <code>source</code> is <code>null</code>, the created dataset will
084     * be empty.
085     *
086     * @param source  the source dataset (<code>null</code> permitted).
087     * @param extract  extract data from rows or columns? (<code>null</code>
088     *                 not permitted).
089     * @param index  the row or column index.
090     */
091    public CategoryToPieDataset(CategoryDataset source,
092                                TableOrder extract,
093                                int index) {
094        if (extract == null) {
095            throw new IllegalArgumentException("Null 'extract' argument.");
096        }
097        this.source = source;
098        if (this.source != null) {
099            this.source.addChangeListener(this);
100        }
101        this.extract = extract;
102        this.index = index;
103    }
104
105    /**
106     * Returns the underlying dataset.
107     *
108     * @return The underlying dataset (possibly <code>null</code>).
109     *
110     * @since 1.0.2
111     */
112    public CategoryDataset getUnderlyingDataset() {
113        return this.source;
114    }
115
116    /**
117     * Returns the extract type, which determines whether data is read from
118     * one row or one column of the underlying dataset.
119     *
120     * @return The extract type.
121     *
122     * @since 1.0.2
123     */
124    public TableOrder getExtractType() {
125        return this.extract;
126    }
127
128    /**
129     * Returns the index of the row or column from which to extract the data.
130     *
131     * @return The extract index.
132     *
133     * @since 1.0.2
134     */
135    public int getExtractIndex() {
136        return this.index;
137    }
138
139    /**
140     * Returns the number of items (values) in the collection.  If the
141     * underlying dataset is <code>null</code>, this method returns zero.
142     *
143     * @return The item count.
144     */
145    public int getItemCount() {
146        int result = 0;
147        if (this.source != null) {
148            if (this.extract == TableOrder.BY_ROW) {
149                result = this.source.getColumnCount();
150            }
151            else if (this.extract == TableOrder.BY_COLUMN) {
152                result = this.source.getRowCount();
153            }
154        }
155        return result;
156    }
157
158    /**
159     * Returns a value from the dataset.
160     *
161     * @param item  the item index (zero-based).
162     *
163     * @return The value (possibly <code>null</code>).
164     *
165     * @throws IndexOutOfBoundsException if <code>item</code> is not in the
166     *     range <code>0</code> to <code>getItemCount() - 1</code>.
167     */
168    public Number getValue(int item) {
169        Number result = null;
170        if (item < 0 || item >= getItemCount()) {
171            // this will include the case where the underlying dataset is null
172            throw new IndexOutOfBoundsException(
173                    "The 'item' index is out of bounds.");
174        }
175        if (this.extract == TableOrder.BY_ROW) {
176            result = this.source.getValue(this.index, item);
177        }
178        else if (this.extract == TableOrder.BY_COLUMN) {
179            result = this.source.getValue(item, this.index);
180        }
181        return result;
182    }
183
184    /**
185     * Returns the key at the specified index.
186     *
187     * @param index  the item index (in the range <code>0</code> to
188     *     <code>getItemCount() - 1</code>).
189     *
190     * @return The key.
191     *
192     * @throws IndexOutOfBoundsException if <code>index</code> is not in the
193     *     specified range.
194     */
195    public Comparable getKey(int index) {
196        Comparable result = null;
197        if (index < 0 || index >= getItemCount()) {
198            // this includes the case where the underlying dataset is null
199            throw new IndexOutOfBoundsException("Invalid 'index': " + index);
200        }
201        if (this.extract == TableOrder.BY_ROW) {
202            result = this.source.getColumnKey(index);
203        }
204        else if (this.extract == TableOrder.BY_COLUMN) {
205            result = this.source.getRowKey(index);
206        }
207        return result;
208    }
209
210    /**
211     * Returns the index for a given key, or <code>-1</code> if there is no
212     * such key.
213     *
214     * @param key  the key.
215     *
216     * @return The index for the key, or <code>-1</code>.
217     */
218    public int getIndex(Comparable key) {
219        int result = -1;
220        if (this.source != null) {
221            if (this.extract == TableOrder.BY_ROW) {
222                result = this.source.getColumnIndex(key);
223            }
224            else if (this.extract == TableOrder.BY_COLUMN) {
225                result = this.source.getRowIndex(key);
226            }
227        }
228        return result;
229    }
230
231    /**
232     * Returns the keys for the dataset.
233     * <p>
234     * If the underlying dataset is <code>null</code>, this method returns an
235     * empty list.
236     *
237     * @return The keys.
238     */
239    public List getKeys() {
240        List result = Collections.EMPTY_LIST;
241        if (this.source != null) {
242            if (this.extract == TableOrder.BY_ROW) {
243                result = this.source.getColumnKeys();
244            }
245            else if (this.extract == TableOrder.BY_COLUMN) {
246                result = this.source.getRowKeys();
247            }
248        }
249        return result;
250    }
251
252    /**
253     * Returns the value for a given key.  If the key is not recognised, the
254     * method should return <code>null</code> (but note that <code>null</code>
255     * can be associated with a valid key also).
256     *
257     * @param key  the key.
258     *
259     * @return The value (possibly <code>null</code>).
260     */
261    public Number getValue(Comparable key) {
262        Number result = null;
263        int keyIndex = getIndex(key);
264        if (keyIndex != -1) {
265            if (this.extract == TableOrder.BY_ROW) {
266                result = this.source.getValue(this.index, keyIndex);
267            }
268            else if (this.extract == TableOrder.BY_COLUMN) {
269                result = this.source.getValue(keyIndex, this.index);
270            }
271        }
272        return result;
273    }
274
275    /**
276     * Sends a {@link DatasetChangeEvent} to all registered listeners, with
277     * this (not the underlying) dataset as the source.
278     *
279     * @param event  the event (ignored, a new event with this dataset as the
280     *     source is sent to the listeners).
281     */
282    public void datasetChanged(DatasetChangeEvent event) {
283        fireDatasetChanged();
284    }
285
286    /**
287     * Tests this dataset for equality with an arbitrary object, returning
288     * <code>true</code> if <code>obj</code> is a dataset containing the same
289     * keys and values in the same order as this dataset.
290     *
291     * @param obj  the object to test (<code>null</code> permitted).
292     *
293     * @return A boolean.
294     */
295    public boolean equals(Object obj) {
296        if (obj == this) {
297            return true;
298        }
299        if (!(obj instanceof PieDataset)) {
300            return false;
301        }
302        PieDataset that = (PieDataset) obj;
303        int count = getItemCount();
304        if (that.getItemCount() != count) {
305            return false;
306        }
307        for (int i = 0; i < count; i++) {
308            Comparable k1 = getKey(i);
309            Comparable k2 = that.getKey(i);
310            if (!k1.equals(k2)) {
311                return false;
312            }
313
314            Number v1 = getValue(i);
315            Number v2 = that.getValue(i);
316            if (v1 == null) {
317                if (v2 != null) {
318                    return false;
319                }
320            }
321            else {
322                if (!v1.equals(v2)) {
323                    return false;
324                }
325            }
326        }
327        return true;
328    }
329
330}