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     * XYItemLabelGenerator.java
029     * -------------------------
030     * (C) Copyright 2001-2005, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   -;
034     *
035     * $Id: XYItemLabelGenerator.java,v 1.1.2.1 2005/10/25 20:49:02 mungady Exp $
036     *
037     * Changes
038     * -------
039     * 13-Dec-2001 : Version 1 (DG);
040     * 16-Jan-2002 : Completed Javadocs (DG);
041     * 13-Jun-2002 : Correction to Javadoc comments (DG);
042     * 26-Sep-2002 : Fixed errors reported by Checkstyle (DG);
043     * 25-Feb-2004 : Renamed XYToolTipGenerator --> XYItemLabelGenerator (DG);
044     * 15-Apr-2004 : Moved the generateToolTip() method to a separate 
045     *               interface (DG);
046     * 11-May-2004 : Renamed XYItemLabelGenerator --> XYLabelGenerator (DG);
047     * 20-Apr-2005 : Reverted name change of 11-May-2004 (DG);
048     *
049     */
050    
051    package org.jfree.chart.labels;
052    
053    import org.jfree.data.xy.XYDataset;
054    
055    /**
056     * Interface for a label generator for plots that use data from an 
057     * {@link XYDataset}.
058     */
059    public interface XYItemLabelGenerator {
060    
061        /**
062         * Generates a label for the specified item. The label is typically a 
063         * formatted version of the data value, but any text can be used.
064         *
065         * @param dataset  the dataset (<code>null</code> not permitted).
066         * @param series  the series index (zero-based).
067         * @param item  the item index (zero-based).
068         *
069         * @return The label (possibly <code>null</code>).
070         */
071        public String generateLabel(XYDataset dataset, int series, int item);
072    
073    }