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     * StandardXYURLGenerator.java
029     * ---------------------------
030     * (C) Copyright 2002-2005, by Richard Atkinson and Contributors.
031     *
032     * Original Author:  Richard Atkinson;
033     * Contributors:     David Gilbert (for Object Refinery Limited);
034     *
035     * $Id: StandardXYURLGenerator.java,v 1.6.2.1 2005/10/25 20:59:31 mungady Exp $
036     *
037     * Changes:
038     * --------
039     * 05-Aug-2002 : Version 1, contributed by Richard Atkinson;
040     * 29-Aug-2002 : New constructor and member variables to customise series and 
041     *               item parameter names (RA);
042     * 09-Oct-2002 : Fixed errors reported by Checkstyle (DG);
043     * 23-Mar-2003 : Implemented Serializable (DG);
044     * 01-Mar-2004 : Added equals() method (DG);
045     * 13-Jan-2005 : Modified for XHTML 1.0 compliance (DG);
046     *
047     */
048    
049    package org.jfree.chart.urls;
050    
051    import java.io.Serializable;
052    
053    import org.jfree.data.xy.XYDataset;
054    import org.jfree.util.ObjectUtilities;
055    
056    /**
057     * A URL generator.
058     *
059     * @author Richard Atkinson
060     */
061    public class StandardXYURLGenerator implements XYURLGenerator, Serializable {
062        
063        /** For serialization. */
064        private static final long serialVersionUID = -1771624523496595382L;
065        
066        /** The default prefix. */
067        public static final String DEFAULT_PREFIX = "index.html";
068        
069        /** The default series parameter. */
070        public static final String DEFAULT_SERIES_PARAMETER = "series";
071        
072        /** The default item parameter. */
073        public static final String DEFAULT_ITEM_PARAMETER = "item";
074        
075        /** Prefix to the URL */
076        private String prefix;
077    
078        /** Series parameter name to go in each URL */
079        private String seriesParameterName;
080    
081        /** Item parameter name to go in each URL */
082        private String itemParameterName;
083    
084        /**
085         * Creates a new default generator.  This constructor is equivalent to
086         * calling <code>StandardXYURLGenerator("index.html", "series", "item");
087         * </code>.
088         */
089        public StandardXYURLGenerator() {
090            this(DEFAULT_PREFIX, DEFAULT_SERIES_PARAMETER, DEFAULT_ITEM_PARAMETER);
091        }
092    
093        /**
094         * Creates a new generator with the specified prefix.  This constructor 
095         * is equivalent to calling 
096         * <code>StandardXYURLGenerator(prefix, "series", "item");</code>.
097         *
098         * @param prefix  the prefix to the URL (<code>null</code> not permitted).
099         */
100        public StandardXYURLGenerator(String prefix) {
101            this(prefix, DEFAULT_SERIES_PARAMETER, DEFAULT_ITEM_PARAMETER);
102        }
103    
104        /**
105         * Constructor that overrides all the defaults
106         *
107         * @param prefix  the prefix to the URL (<code>null</code> not permitted).
108         * @param seriesParameterName  the name of the series parameter to go in 
109         *                             each URL (<code>null</code> not permitted).
110         * @param itemParameterName  the name of the item parameter to go in each
111         *                           URL (<code>null</code> not permitted).
112         */
113        public StandardXYURLGenerator(String prefix,
114                                      String seriesParameterName,
115                                      String itemParameterName) {
116            if (prefix == null) {
117                throw new IllegalArgumentException("Null 'prefix' argument.");
118            }
119            if (seriesParameterName == null) {
120                throw new IllegalArgumentException(
121                    "Null 'seriesParameterName' argument."
122                );
123            }
124            if (itemParameterName == null) {
125                throw new IllegalArgumentException(
126                    "Null 'itemParameterName' argument."
127                );
128            }
129            this.prefix = prefix;
130            this.seriesParameterName = seriesParameterName;
131            this.itemParameterName = itemParameterName;
132        }
133    
134        /**
135         * Generates a URL for a particular item within a series.
136         *
137         * @param dataset  the dataset.
138         * @param series  the series number (zero-based index).
139         * @param item  the item number (zero-based index).
140         *
141         * @return The generated URL.
142         */
143        public String generateURL(XYDataset dataset, int series, int item) {
144            String url = this.prefix;
145            boolean firstParameter = url.indexOf("?") == -1;
146            url += firstParameter ? "?" : "&amp;";
147            url += this.seriesParameterName + "=" + series
148                + "&amp;" + this.itemParameterName + "=" + item;
149            return url;
150        }
151    
152        /**
153         * Tests this generator for equality with an arbitrary object.
154         * 
155         * @param obj  the object (<code>null</code> permitted).
156         * 
157         * @return A boolean.
158         */
159        public boolean equals(Object obj) {
160            if (obj == this) {
161                return true;   
162            }
163            if (!(obj instanceof StandardXYURLGenerator)) {
164                return false;
165            }
166            StandardXYURLGenerator that = (StandardXYURLGenerator) obj;
167            if (!ObjectUtilities.equal(that.prefix, this.prefix)) {
168                return false;
169            }
170            if (!ObjectUtilities.equal(that.seriesParameterName, 
171                    this.seriesParameterName)) {
172                return false;
173            }
174            if (!ObjectUtilities.equal(that.itemParameterName, 
175                    this.itemParameterName)) {
176                return false;
177            }
178            return true;
179        }
180        
181    }