001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2013, 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 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
025 * Other names may be trademarks of their respective owners.]
026 *
027 * ---------------
028 * XYZDataset.java
029 * ---------------
030 * (C) Copyright 2001-2008, by Object Refinery Limited.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * Changes
036 * -------
037 * 31-Oct-2001 : Initial version (DG);
038 * 05-May-2004 : Added getZ() method;
039 * 15-Jul-2004 : Switched getZ() and getZValue() methods (DG);
040 * 18-Aug-2004 : Moved from org.jfree.data --> org.jfree.data.xy (DG);
041 *
042 */
043
044package org.jfree.data.xy;
045
046/**
047 * The interface through which JFreeChart obtains data in the form of (x, y, z)
048 * items - used for XY and XYZ plots.
049 */
050public interface XYZDataset extends XYDataset {
051
052    /**
053     * Returns the z-value for the specified series and item.
054     *
055     * @param series  the series index (zero-based).
056     * @param item  the item index (zero-based).
057     *
058     * @return The z-value (possibly <code>null</code>).
059     */
060    public Number getZ(int series, int item);
061
062    /**
063     * Returns the z-value (as a double primitive) for an item within a series.
064     *
065     * @param series  the series (zero-based index).
066     * @param item  the item (zero-based index).
067     *
068     * @return The z-value.
069     */
070    public double getZValue(int series, int item);
071
072}