    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     * AbstractXYZDataset.java
    029     * -----------------------
    030     * (C) Copyright 2004, by Object Refinery Limited.
    031     *
    032     * Original Author:  David Gilbert (for Object Refinery Limited).
    033     * Contributor(s):   -;
    034     *
    035     * $Id: AbstractXYZDataset.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 getZ() and getZValue() (DG);
    041     *
    042     */
    043
    044    package org.jfree.data.xy;
    045
    046
    047    /**
    048     * An base class that you can use to create new implementations of the
    049     * {@link XYZDataset} interface.
    050     */
    051    public abstract class AbstractXYZDataset extends AbstractXYDataset
    052                                             implements XYZDataset {
    053
    054        /**
    055         * Returns the z-value (as a double primitive) for an item within a series.
    056         *
    057         * @param series  the series (zero-based index).
    058         * @param item  the item (zero-based index).
    059         *
    060         * @return The z-value.
    061         */
    062        public double getZValue(int series, int item) {
    063            double result = Double.NaN;
    064            Number z = getZ(series, item);
    065            if (z != null) {
    066                result = z.doubleValue();
    067            }
    068            return result;
    069        }
    070
    071    }