Java tutorial
/* =========================================================== * JFreeChart : a free chart library for the Java(tm) platform * =========================================================== * * (C) Copyright 2000-2013, by Object Refinery Limited and Contributors. * * Project Info: http://www.jfree.org/jfreechart/index.html * * This library is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 of the License, or * (at your option) any later version. * * This library is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public * License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, * USA. * * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. * Other names may be trademarks of their respective owners.] * * ----------------------- * AbstractXYZDataset.java * ----------------------- * (C) Copyright 2004-2008, by Object Refinery Limited. * * Original Author: David Gilbert (for Object Refinery Limited). * Contributor(s): -; * * Changes * ------- * 05-May-2004 : Version 1 (DG); * 15-Jul-2004 : Switched getZ() and getZValue() (DG); * */ package org.jfree.data.xy; /** * An base class that you can use to create new implementations of the * {@link XYZDataset} interface. */ public abstract class AbstractXYZDataset extends AbstractXYDataset implements XYZDataset { /** * Returns the z-value (as a double primitive) for an item within a series. * * @param series the series (zero-based index). * @param item the item (zero-based index). * * @return The z-value. */ @Override public double getZValue(int series, int item) { double result = Double.NaN; Number z = getZ(series, item); if (z != null) { result = z.doubleValue(); } return result; } }