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 * CategoryDatasetHandler.java
029 * ---------------------------
030 * (C) Copyright 2003-2005, by Object Refinery Limited and Contributors.
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): -;
034 *
035 * $Id: CategoryDatasetHandler.java,v 1.3.2.1 2005/10/25 21:36:10 mungady Exp $
036 *
037 * Changes
038 * -------
039 * 23-Jan-2003 : Version 1 (DG);
040 *
041 */
042
043 package org.jfree.data.xml;
044
045 import org.jfree.data.category.CategoryDataset;
046 import org.jfree.data.category.DefaultCategoryDataset;
047 import org.xml.sax.Attributes;
048 import org.xml.sax.SAXException;
049 import org.xml.sax.helpers.DefaultHandler;
050
051 /**
052 * A SAX handler for reading a {@link CategoryDataset} from an XML file.
053 */
054 public class CategoryDatasetHandler extends RootHandler implements DatasetTags {
055
056 /** The dataset under construction. */
057 private DefaultCategoryDataset dataset;
058
059 /**
060 * Creates a new handler.
061 */
062 public CategoryDatasetHandler() {
063 this.dataset = null;
064 }
065
066 /**
067 * Returns the dataset.
068 *
069 * @return The dataset.
070 */
071 public CategoryDataset getDataset() {
072 return this.dataset;
073 }
074
075 /**
076 * Adds an item to the dataset.
077 *
078 * @param rowKey the row key.
079 * @param columnKey the column key.
080 * @param value the value.
081 */
082 public void addItem(Comparable rowKey, Comparable columnKey, Number value) {
083 this.dataset.addValue(value, rowKey, columnKey);
084 }
085
086 /**
087 * The start of an element.
088 *
089 * @param namespaceURI the namespace.
090 * @param localName the element name.
091 * @param qName the element name.
092 * @param atts the element attributes.
093 *
094 * @throws SAXException for errors.
095 */
096 public void startElement(String namespaceURI,
097 String localName,
098 String qName,
099 Attributes atts) throws SAXException {
100
101 DefaultHandler current = getCurrentHandler();
102 if (current != this) {
103 current.startElement(namespaceURI, localName, qName, atts);
104 }
105 else if (qName.equals(CATEGORYDATASET_TAG)) {
106 this.dataset = new DefaultCategoryDataset();
107 }
108 else if (qName.equals(SERIES_TAG)) {
109 CategorySeriesHandler subhandler = new CategorySeriesHandler(this);
110 getSubHandlers().push(subhandler);
111 subhandler.startElement(namespaceURI, localName, qName, atts);
112 }
113 else {
114 throw new SAXException("Element not recognised: " + qName);
115 }
116
117 }
118
119 /**
120 * The end of an element.
121 *
122 * @param namespaceURI the namespace.
123 * @param localName the element name.
124 * @param qName the element name.
125 *
126 * @throws SAXException for errors.
127 */
128 public void endElement(String namespaceURI,
129 String localName,
130 String qName) throws SAXException {
131
132 DefaultHandler current = getCurrentHandler();
133 if (current != this) {
134 current.endElement(namespaceURI, localName, qName);
135 }
136
137 }
138
139 }