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     * CategoryToolTipGenerator.java
029     * -----------------------------
030     * (C) Copyright 2001-2004, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   -;
034     *
035     * $Id: CategoryToolTipGenerator.java,v 1.3.2.1 2005/10/25 20:49:02 mungady Exp $
036     *
037     * Changes
038     * -------
039     * 15-Apr-2004 : Separated tool tip method from CategoryItemLabelGenerator 
040     *               interface (DG);
041     *
042     */
043    
044    package org.jfree.chart.labels;
045    
046    import org.jfree.data.category.CategoryDataset;
047    
048    /**
049     * A <i>category tool tip generator</i> is an object that can be assigned to a 
050     * {@link org.jfree.chart.renderer.category.CategoryItemRenderer} and that 
051     * assumes responsibility for creating text items to be used as tooltips for the
052     * items in a {@link org.jfree.chart.plot.CategoryPlot}. 
053     * <p>
054     * To assist with cloning charts, classes that implement this interface should 
055     * also implement the <code>org.jfree.util.PublicCloneable</code> interface (in
056     * JCommon).
057     */
058    public interface CategoryToolTipGenerator {
059    
060        /**
061         * Generates the tool tip text for an item in a dataset.  Note: in the 
062         * current dataset implementation, each row is a series, and each column 
063         * contains values for a particular category.
064         *
065         * @param dataset  the dataset (<code>null</code> not permitted).
066         * @param row  the row index (zero-based).
067         * @param column  the column index (zero-based).
068         *
069         * @return The tooltip text (possibly <code>null</code>).
070         */
071        public String generateToolTip(CategoryDataset dataset, int row, int column);
072        
073    }