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     * StandardXYURLGenerator.java
029     * ---------------------------
030     * (C) Copyright 2002-2007, by Richard Atkinson and Contributors.
031     *
032     * Original Author:  Richard Atkinson;
033     * Contributors:     David Gilbert (for Object Refinery Limited);
034     *
035     * Changes:
036     * --------
037     * 05-Aug-2002 : Version 1, contributed by Richard Atkinson;
038     * 29-Aug-2002 : New constructor and member variables to customise series and 
039     *               item parameter names (RA);
040     * 09-Oct-2002 : Fixed errors reported by Checkstyle (DG);
041     * 23-Mar-2003 : Implemented Serializable (DG);
042     * 01-Mar-2004 : Added equals() method (DG);
043     * 13-Jan-2005 : Modified for XHTML 1.0 compliance (DG);
044     * ------------- JFREECHART 1.0.x ---------------------------------------------
045     * 02-Feb-2007 : Removed author tags from all over JFreeChart sources (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    public class StandardXYURLGenerator implements XYURLGenerator, Serializable {
060        
061        /** For serialization. */
062        private static final long serialVersionUID = -1771624523496595382L;
063        
064        /** The default prefix. */
065        public static final String DEFAULT_PREFIX = "index.html";
066        
067        /** The default series parameter. */
068        public static final String DEFAULT_SERIES_PARAMETER = "series";
069        
070        /** The default item parameter. */
071        public static final String DEFAULT_ITEM_PARAMETER = "item";
072        
073        /** Prefix to the URL */
074        private String prefix;
075    
076        /** Series parameter name to go in each URL */
077        private String seriesParameterName;
078    
079        /** Item parameter name to go in each URL */
080        private String itemParameterName;
081    
082        /**
083         * Creates a new default generator.  This constructor is equivalent to
084         * calling <code>StandardXYURLGenerator("index.html", "series", "item");
085         * </code>.
086         */
087        public StandardXYURLGenerator() {
088            this(DEFAULT_PREFIX, DEFAULT_SERIES_PARAMETER, DEFAULT_ITEM_PARAMETER);
089        }
090    
091        /**
092         * Creates a new generator with the specified prefix.  This constructor 
093         * is equivalent to calling 
094         * <code>StandardXYURLGenerator(prefix, "series", "item");</code>.
095         *
096         * @param prefix  the prefix to the URL (<code>null</code> not permitted).
097         */
098        public StandardXYURLGenerator(String prefix) {
099            this(prefix, DEFAULT_SERIES_PARAMETER, DEFAULT_ITEM_PARAMETER);
100        }
101    
102        /**
103         * Constructor that overrides all the defaults
104         *
105         * @param prefix  the prefix to the URL (<code>null</code> not permitted).
106         * @param seriesParameterName  the name of the series parameter to go in 
107         *                             each URL (<code>null</code> not permitted).
108         * @param itemParameterName  the name of the item parameter to go in each
109         *                           URL (<code>null</code> not permitted).
110         */
111        public StandardXYURLGenerator(String prefix,
112                                      String seriesParameterName,
113                                      String itemParameterName) {
114            if (prefix == null) {
115                throw new IllegalArgumentException("Null 'prefix' argument.");
116            }
117            if (seriesParameterName == null) {
118                throw new IllegalArgumentException(
119                        "Null 'seriesParameterName' argument.");
120            }
121            if (itemParameterName == null) {
122                throw new IllegalArgumentException(
123                        "Null 'itemParameterName' argument.");
124            }
125            this.prefix = prefix;
126            this.seriesParameterName = seriesParameterName;
127            this.itemParameterName = itemParameterName;
128        }
129    
130        /**
131         * Generates a URL for a particular item within a series.
132         *
133         * @param dataset  the dataset.
134         * @param series  the series number (zero-based index).
135         * @param item  the item number (zero-based index).
136         *
137         * @return The generated URL.
138         */
139        public String generateURL(XYDataset dataset, int series, int item) {
140            String url = this.prefix;
141            boolean firstParameter = url.indexOf("?") == -1;
142            url += firstParameter ? "?" : "&amp;";
143            url += this.seriesParameterName + "=" + series
144                    + "&amp;" + this.itemParameterName + "=" + item;
145            return url;
146        }
147    
148        /**
149         * Tests this generator for equality with an arbitrary object.
150         * 
151         * @param obj  the object (<code>null</code> permitted).
152         * 
153         * @return A boolean.
154         */
155        public boolean equals(Object obj) {
156            if (obj == this) {
157                return true;   
158            }
159            if (!(obj instanceof StandardXYURLGenerator)) {
160                return false;
161            }
162            StandardXYURLGenerator that = (StandardXYURLGenerator) obj;
163            if (!ObjectUtilities.equal(that.prefix, this.prefix)) {
164                return false;
165            }
166            if (!ObjectUtilities.equal(that.seriesParameterName, 
167                    this.seriesParameterName)) {
168                return false;
169            }
170            if (!ObjectUtilities.equal(that.itemParameterName, 
171                    this.itemParameterName)) {
172                return false;
173            }
174            return true;
175        }
176        
177    }