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     * StandardXYSeriesLabelGenerator.java
029     * -----------------------------------
030     * (C) Copyright 2004, 2005, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   -;
034     *
035     * $Id: StandardXYSeriesLabelGenerator.java,v 1.5.2.1 2005/10/25 20:49:02 mungady Exp $
036     *
037     * Changes
038     * -------
039     * 16-Nov-2004 : Version 1 (DG);
040     *
041     */
042    
043    package org.jfree.chart.labels;
044    
045    import java.io.Serializable;
046    import java.text.MessageFormat;
047    
048    import org.jfree.data.xy.XYDataset;
049    import org.jfree.util.PublicCloneable;
050    
051    /**
052     * A standard series label generator for plots that use data from 
053     * an {@link org.jfree.data.xy.XYDataset}.
054     */
055    public class StandardXYSeriesLabelGenerator implements XYSeriesLabelGenerator, 
056                                                           Cloneable, 
057                                                           PublicCloneable,
058                                                           Serializable {
059    
060        /** For serialization. */
061        private static final long serialVersionUID = 1916017081848400024L;
062        
063        /** The default item label format. */
064        public static final String DEFAULT_LABEL_FORMAT = "{0}";
065        
066        /** The format pattern. */
067        private String formatPattern;
068    
069        /**
070         * Creates a default series label generator (uses 
071         * {@link #DEFAULT_LABEL_FORMAT}).
072         */
073        public StandardXYSeriesLabelGenerator() {
074            this(DEFAULT_LABEL_FORMAT);
075        }
076        
077        /**
078         * Creates a new series label generator.
079         * 
080         * @param format  the format pattern (<code>null</code> not permitted).
081         */
082        public StandardXYSeriesLabelGenerator(String format) {
083            if (format == null) {
084                throw new IllegalArgumentException("Null 'format' argument.");
085            }
086            this.formatPattern = format;
087        }
088    
089        /**
090         * Generates a label for the specified series.  This label will be
091         * used for the chart legend.
092         * 
093         * @param dataset  the dataset (<code>null</code> not permitted).
094         * @param series  the series.
095         * 
096         * @return A series label.
097         */
098        public String generateLabel(XYDataset dataset, int series) {
099            if (dataset == null) {
100                throw new IllegalArgumentException("Null 'dataset' argument.");
101            }
102            String label = MessageFormat.format(
103                this.formatPattern, createItemArray(dataset, series)
104            );
105            return label;
106        }
107    
108        /**
109         * Creates the array of items that can be passed to the 
110         * {@link MessageFormat} class for creating labels.
111         *
112         * @param dataset  the dataset (<code>null</code> not permitted).
113         * @param series  the series (zero-based index).
114         *
115         * @return The items (never <code>null</code>).
116         */
117        protected Object[] createItemArray(XYDataset dataset, int series) {
118            Object[] result = new Object[1];
119            result[0] = dataset.getSeriesKey(series).toString();
120            return result;
121        }
122    
123        /**
124         * Returns an independent copy of the generator.
125         * 
126         * @return A clone.
127         * 
128         * @throws CloneNotSupportedException if cloning is not supported.
129         */
130        public Object clone() throws CloneNotSupportedException { 
131            return super.clone();
132        }
133        
134        /**
135         * Tests this object for equality with an arbitrary object.
136         *
137         * @param obj  the other object (<code>null</code> permitted).
138         *
139         * @return A boolean.
140         */
141        public boolean equals(Object obj) {
142            if (obj == this) {
143                return true;
144            }
145            if (!(obj instanceof StandardXYSeriesLabelGenerator)) {
146                return false;
147            }
148            if (!super.equals(obj)) {
149                return false;
150            }
151            return true;
152        }
153    
154    }