001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2007, 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 * StandardCategorySeriesLabelGenerator.java
029 * -----------------------------------------
030 * (C) Copyright 2005-2007, by Object Refinery Limited.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * Changes
036 * -------
037 * 20-Apr-2005 : Version 1 (DG);
038 * ------------- JFREECHART 1.0.x ---------------------------------------------
039 * 03-May-2006 : Fixed equals() method (bug 1481102) (DG);
040 *
041 */
042
043package org.jfree.chart.labels;
044
045import java.io.Serializable;
046import java.text.MessageFormat;
047
048import org.jfree.data.category.CategoryDataset;
049import org.jfree.util.PublicCloneable;
050
051/**
052 * A standard series label generator for plots that use data from 
053 * a {@link org.jfree.data.category.CategoryDataset}.
054 */
055public class StandardCategorySeriesLabelGenerator implements 
056    CategorySeriesLabelGenerator, Cloneable, PublicCloneable, Serializable {
057
058    /** For serialization. */
059    private static final long serialVersionUID = 4630760091523940820L;
060    
061    /** The default item label format. */
062    public static final String DEFAULT_LABEL_FORMAT = "{0}";
063    
064    /** The format pattern. */
065    private String formatPattern;
066
067    /**
068     * Creates a default series label generator (uses 
069     * {@link #DEFAULT_LABEL_FORMAT}).
070     */
071    public StandardCategorySeriesLabelGenerator() {
072        this(DEFAULT_LABEL_FORMAT);
073    }
074    
075    /**
076     * Creates a new series label generator.
077     * 
078     * @param format  the format pattern (<code>null</code> not permitted).
079     */
080    public StandardCategorySeriesLabelGenerator(String format) {
081        if (format == null) {
082            throw new IllegalArgumentException("Null 'format' argument.");
083        }
084        this.formatPattern = format;
085    }
086
087    /**
088     * Generates a label for the specified series.
089     * 
090     * @param dataset  the dataset (<code>null</code> not permitted).
091     * @param series  the series.
092     * 
093     * @return A series label.
094     */
095    public String generateLabel(CategoryDataset dataset, int series) {
096        if (dataset == null) {
097            throw new IllegalArgumentException("Null 'dataset' argument.");
098        }
099        String label = MessageFormat.format(this.formatPattern, 
100                createItemArray(dataset, series));
101        return label;
102    }
103
104    /**
105     * Creates the array of items that can be passed to the 
106     * {@link MessageFormat} class for creating labels.
107     *
108     * @param dataset  the dataset (<code>null</code> not permitted).
109     * @param series  the series (zero-based index).
110     *
111     * @return The items (never <code>null</code>).
112     */
113    protected Object[] createItemArray(CategoryDataset dataset, int series) {
114        Object[] result = new Object[1];
115        result[0] = dataset.getRowKey(series).toString();
116        return result;
117    }
118
119    /**
120     * Returns an independent copy of the generator.
121     * 
122     * @return A clone.
123     * 
124     * @throws CloneNotSupportedException if cloning is not supported.
125     */
126    public Object clone() throws CloneNotSupportedException { 
127        return super.clone();
128    }
129    
130    /**
131     * Tests this object for equality with an arbitrary object.
132     *
133     * @param obj  the other object (<code>null</code> permitted).
134     *
135     * @return A boolean.
136     */
137    public boolean equals(Object obj) {
138        if (obj == this) {
139            return true;
140        }
141        if (!(obj instanceof StandardCategorySeriesLabelGenerator)) {
142            return false;
143        }
144        StandardCategorySeriesLabelGenerator that 
145                = (StandardCategorySeriesLabelGenerator) obj;
146        if (!this.formatPattern.equals(that.formatPattern)) {
147            return false;
148        }
149        return true;
150    }
151
152}