001 /* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2008, 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 * CategoryItemLabelGenerator.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 * 26-Sep-2002 : Fixed errors reported by Checkstyle (DG);
040 * 24-Oct-2002 : Method now specifies category index (DG);
041 * 05-Nov-2002 : Replaced reference to CategoryDataset with TableDataset (DG);
042 * 21-Jan-2003 : TableDataset merged with CategoryDataset (DG);
043 * 10-Apr-2003 : Changed CategoryDataset --> KeyedValues2DDataset (DG);
044 * 01-May-2003 : Added generateValueLabel() method (with a plan to renaming
045 * this interface to reflect its more general use) (DG);
046 * 09-Jun-2003 : Renamed CategoryToolTipGenerator
047 * --> CategoryItemLabelGenerator (DG);
048 * 13-Aug-2003 : Added clone() method (DG);
049 * 12-Feb-2004 : Removed clone() method (DG);
050 * 15-Apr-2004 : Moved generateToolTip() method into CategoryToolTipGenerator
051 * interface (DG);
052 * 11-May-2004 : Renamed CategoryItemLabelGenerator
053 * --> CategoryLabelGenerator (DG);
054 * 31-Jan-2005 : Added generateRowLabel() and generateColumnLabel()
055 * methods (DG);
056 * 20-Apr-2005 : Reverted name change of 11-May-2004 (DG);
057 *
058 */
059
060 package org.jfree.chart.labels;
061
062 import org.jfree.data.category.CategoryDataset;
063
064 /**
065 * A <i>category item label generator</i> is an object that can be assigned to a
066 * {@link org.jfree.chart.renderer.category.CategoryItemRenderer} and that
067 * assumes responsibility for creating text items to be used as labels for the
068 * items in a {@link org.jfree.chart.plot.CategoryPlot}.
069 * <p>
070 * To assist with cloning charts, classes that implement this interface should
071 * also implement the {@link org.jfree.util.PublicCloneable} interface.
072 */
073 public interface CategoryItemLabelGenerator {
074
075 /**
076 * Generates a label for the specified row.
077 *
078 * @param dataset the dataset (<code>null</code> not permitted).
079 * @param row the row index (zero-based).
080 *
081 * @return The label.
082 */
083 public String generateRowLabel(CategoryDataset dataset, int row);
084
085 /**
086 * Generates a label for the specified row.
087 *
088 * @param dataset the dataset (<code>null</code> not permitted).
089 * @param column the column index (zero-based).
090 *
091 * @return The label.
092 */
093 public String generateColumnLabel(CategoryDataset dataset, int column);
094
095 /**
096 * Generates a label for the specified item. The label is typically a
097 * formatted version of the data value, but any text can be used.
098 *
099 * @param dataset the dataset (<code>null</code> not permitted).
100 * @param row the row index (zero-based).
101 * @param column the column index (zero-based).
102 *
103 * @return The label (possibly <code>null</code>).
104 */
105 public String generateLabel(CategoryDataset dataset, int row, int column);
106
107 }