    001/* ===========================================================
    002 * JFreeChart : a free chart library for the Java(tm) platform
    003 * ===========================================================
    004 *
    005 * (C) Copyright 2000-2011, 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 * XYItemLabelGenerator.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 * 13-Dec-2001 : Version 1 (DG);
    038 * 16-Jan-2002 : Completed Javadocs (DG);
    039 * 13-Jun-2002 : Correction to Javadoc comments (DG);
    040 * 26-Sep-2002 : Fixed errors reported by Checkstyle (DG);
    041 * 25-Feb-2004 : Renamed XYToolTipGenerator --> XYItemLabelGenerator (DG);
    042 * 15-Apr-2004 : Moved the generateToolTip() method to a separate
    043 *               interface (DG);
    044 * 11-May-2004 : Renamed XYItemLabelGenerator --> XYLabelGenerator (DG);
    045 * 20-Apr-2005 : Reverted name change of 11-May-2004 (DG);
    046 *
    047 */
    048
    049package org.jfree.chart.labels;
    050
    051import org.jfree.data.xy.XYDataset;
    052
    053/**
    054 * Interface for a label generator for plots that use data from an
    055 * {@link XYDataset}.
    056 */
    057public interface XYItemLabelGenerator {
    058
    059    /**
    060     * Generates a label for the specified item. The label is typically a
    061     * formatted version of the data value, but any text can be used.
    062     *
    063     * @param dataset  the dataset (<code>null</code> not permitted).
    064     * @param series  the series index (zero-based).
    065     * @param item  the item index (zero-based).
    066     *
    067     * @return The label (possibly <code>null</code>).
    068     */
    069    public String generateLabel(XYDataset dataset, int series, int item);
    070
    071}