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     * XYBarDataset.java
029     * -----------------
030     * (C) Copyright 2004, 2005, by Object Refinery Limited and Contributors.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   -;
034     *
035     * $Id: XYBarDataset.java,v 1.4.2.1 2005/10/25 21:36:51 mungady Exp $
036     *
037     * Changes
038     * -------
039     * 02-Mar-2004 : Version 1 (DG);
040     * 05-May-2004 : Now extends AbstractIntervalXYDataset (DG);
041     * 15-Jul-2004 : Switched getX() with getXValue() and getY() with 
042     *               getYValue() (DG);
043     *
044     */
045    
046    package org.jfree.data.xy;
047    
048    import org.jfree.data.general.DatasetChangeEvent;
049    import org.jfree.data.general.DatasetChangeListener;
050    
051    /**
052     * A dataset wrapper class that converts a standard {@link XYDataset} into an
053     * {@link IntervalXYDataset} suitable for use in creating XY bar charts.
054     */
055    public class XYBarDataset extends AbstractIntervalXYDataset
056                              implements IntervalXYDataset, DatasetChangeListener {
057        
058        /** The underlying dataset. */
059        private XYDataset underlying;
060        
061        /** The bar width. */
062        private double barWidth;
063        
064        /**
065         * Creates a new dataset.
066         * 
067         * @param underlying  the underlying dataset.
068         * @param barWidth  the width of the bars.
069         */
070        public XYBarDataset(XYDataset underlying, double barWidth) {
071            this.underlying = underlying;   
072            this.underlying.addChangeListener(this);
073            this.barWidth = barWidth;
074        }
075    
076        /**
077         * Returns the number of series in the dataset.
078         *
079         * @return The series count.
080         */
081        public int getSeriesCount() {
082            return this.underlying.getSeriesCount();   
083        }
084    
085        /**
086         * Returns the key for a series.
087         *
088         * @param series  the series index (zero-based).
089         *
090         * @return The series key.
091         */
092        public Comparable getSeriesKey(int series) {
093            return this.underlying.getSeriesKey(series);   
094        }
095        
096        /**
097         * Returns the number of items in a series.
098         *
099         * @param series  the series index (zero-based).
100         *
101         * @return The item count.
102         */
103        public int getItemCount(int series) {
104            return this.underlying.getItemCount(series);   
105        }
106    
107        /**
108         * Returns the x-value for an item within a series.  The x-values may or 
109         * may not be returned in ascending order, that is up to the class 
110         * implementing the interface.
111         *
112         * @param series  the series index (zero-based).
113         * @param item  the item index (zero-based).
114         *
115         * @return The x-value.
116         */
117        public Number getX(int series, int item) {
118            return this.underlying.getX(series, item);   
119        }
120    
121        /**
122         * Returns the y-value for an item within a series.
123         *
124         * @param series  the series index (zero-based).
125         * @param item  the item index (zero-based).
126         *
127         * @return The y-value (possibly <code>null</code>).
128         */
129        public Number getY(int series, int item) {
130            return this.underlying.getY(series, item);   
131        }
132    
133        /**
134         * Returns the starting X value for the specified series and item.
135         *
136         * @param series  the series index (zero-based).
137         * @param item  the item index (zero-based).
138         *
139         * @return The value.
140         */
141        public Number getStartX(int series, int item) {
142            Number result = null;
143            Number xnum = this.underlying.getX(series, item);
144            if (xnum != null) {
145                 result = new Double(xnum.doubleValue() - this.barWidth / 2.0);   
146            }
147            return result;   
148        }
149    
150        /**
151         * Returns the ending X value for the specified series and item.
152         *
153         * @param series  the series index (zero-based).
154         * @param item  the item index (zero-based).
155         *
156         * @return The value.
157         */
158        public Number getEndX(int series, int item) {
159            Number result = null;
160            Number xnum = this.underlying.getX(series, item);
161            if (xnum != null) {
162                 result = new Double(xnum.doubleValue() + this.barWidth / 2.0);   
163            }
164            return result;   
165        }
166    
167        /**
168         * Returns the starting Y value for the specified series and item.
169         *
170         * @param series  the series index (zero-based).
171         * @param item  the item index (zero-based).
172         *
173         * @return The value.
174         */
175        public Number getStartY(int series, int item) {
176            return this.underlying.getY(series, item);   
177        }
178    
179        /**
180         * Returns the ending Y value for the specified series and item.
181         *
182         * @param series  the series index (zero-based).
183         * @param item  the item index (zero-based).
184         *
185         * @return The value.
186         */
187        public Number getEndY(int series, int item) {
188            return this.underlying.getY(series, item);   
189        }
190    
191        /**
192         * Receives notification of an dataset change event.
193         *
194         * @param event  information about the event.
195         */
196        public void datasetChanged(DatasetChangeEvent event) {
197            this.notifyListeners(event);
198        }
199    
200    }