001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-present, by David Gilbert 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 * XYToolTipGenerator.java
029 * -----------------------
030 * (C) Copyright 2001-present, by David Gilbert.
031 *
032 * Original Author:  David Gilbert;
033 * Contributor(s):   -;
034 *
035 */
036
037package org.jfree.chart.labels;
038
039import org.jfree.data.xy.XYDataset;
040
041/**
042 * Interface for a tooltip generator for plots that use data from an
043 * {@link XYDataset}.
044 */
045public interface XYToolTipGenerator {
046
047    /**
048     * Generates the tooltip text for the specified item.
049     *
050     * @param dataset  the dataset ({@code null} not permitted).
051     * @param series  the series index (zero-based).
052     * @param item  the item index (zero-based).
053     *
054     * @return The tooltip text (possibly {@code null}).
055     */
056    String generateToolTip(XYDataset dataset, int series, int item);
057
058}