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     * AbstractXYDataset.java
029     * ----------------------
030     * (C) Copyright 2004, 2005, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited).
033     * Contributor(s):   -;
034     *
035     * $Id: AbstractXYDataset.java,v 1.2.2.1 2005/10/25 21:36:51 mungady Exp $
036     *
037     * Changes
038     * -------
039     * 05-May-2004 : Version 1 (DG);
040     * 15-Jul-2004 : Switched getX() with getXValue() and getY() with 
041     *               getYValue() (DG);
042     * 18-Aug-2004 : Moved from org.jfree.data --> org.jfree.data.xy (DG);
043     * 
044     */
045    
046    package org.jfree.data.xy;
047    
048    import org.jfree.data.DomainOrder;
049    import org.jfree.data.general.AbstractSeriesDataset;
050    
051    /**
052     * An base class that you can use to create new implementations of the 
053     * {@link XYDataset} interface.
054     */
055    public abstract class AbstractXYDataset extends AbstractSeriesDataset 
056                                            implements XYDataset {
057    
058        /**
059         * Returns the order of the domain (X) values.
060         * 
061         * @return The domain order.
062         */
063        public DomainOrder getDomainOrder() {
064            return DomainOrder.NONE;
065        }
066        
067        /**
068         * Returns the x-value (as a double primitive) for an item within a series.
069         * 
070         * @param series  the series index (zero-based).
071         * @param item  the item index (zero-based).
072         * 
073         * @return The value.
074         */
075        public double getXValue(int series, int item) {
076            double result = Double.NaN;
077            Number x = getX(series, item);
078            if (x != null) {
079                result = x.doubleValue();   
080            }
081            return result;   
082        }
083    
084        /**
085         * Returns the y-value (as a double primitive) for an item within a series.
086         * 
087         * @param series  the series index (zero-based).
088         * @param item  the item index (zero-based).
089         * 
090         * @return The value.
091         */
092        public double getYValue(int series, int item) {
093            double result = Double.NaN;
094            Number y = getY(series, item);
095            if (y != null) {
096                result = y.doubleValue();   
097            }
098            return result;   
099        }
100    
101    }