001 /* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2008, 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 2003-2008, by Object Refinery Limited and Contributors.
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): -;
034 *
035 * Changes
036 * -------
037 * 23-Jan-2003 : Version 1 (DG);
038 *
039 */
040
041 package org.jfree.data.xml;
042
043 import org.jfree.data.category.CategoryDataset;
044 import org.jfree.data.category.DefaultCategoryDataset;
045 import org.xml.sax.Attributes;
046 import org.xml.sax.SAXException;
047 import org.xml.sax.helpers.DefaultHandler;
048
049 /**
050 * A SAX handler for reading a {@link CategoryDataset} from an XML file.
051 */
052 public class CategoryDatasetHandler extends RootHandler implements DatasetTags {
053
054 /** The dataset under construction. */
055 private DefaultCategoryDataset dataset;
056
057 /**
058 * Creates a new handler.
059 */
060 public CategoryDatasetHandler() {
061 this.dataset = null;
062 }
063
064 /**
065 * Returns the dataset.
066 *
067 * @return The dataset.
068 */
069 public CategoryDataset getDataset() {
070 return this.dataset;
071 }
072
073 /**
074 * Adds an item to the dataset.
075 *
076 * @param rowKey the row key.
077 * @param columnKey the column key.
078 * @param value the value.
079 */
080 public void addItem(Comparable rowKey, Comparable columnKey, Number value) {
081 this.dataset.addValue(value, rowKey, columnKey);
082 }
083
084 /**
085 * The start of an element.
086 *
087 * @param namespaceURI the namespace.
088 * @param localName the element name.
089 * @param qName the element name.
090 * @param atts the element attributes.
091 *
092 * @throws SAXException for errors.
093 */
094 public void startElement(String namespaceURI,
095 String localName,
096 String qName,
097 Attributes atts) throws SAXException {
098
099 DefaultHandler current = getCurrentHandler();
100 if (current != this) {
101 current.startElement(namespaceURI, localName, qName, atts);
102 }
103 else if (qName.equals(CATEGORYDATASET_TAG)) {
104 this.dataset = new DefaultCategoryDataset();
105 }
106 else if (qName.equals(SERIES_TAG)) {
107 CategorySeriesHandler subhandler = new CategorySeriesHandler(this);
108 getSubHandlers().push(subhandler);
109 subhandler.startElement(namespaceURI, localName, qName, atts);
110 }
111 else {
112 throw new SAXException("Element not recognised: " + qName);
113 }
114
115 }
116
117 /**
118 * The end of an element.
119 *
120 * @param namespaceURI the namespace.
121 * @param localName the element name.
122 * @param qName the element name.
123 *
124 * @throws SAXException for errors.
125 */
126 public void endElement(String namespaceURI,
127 String localName,
128 String qName) throws SAXException {
129
130 DefaultHandler current = getCurrentHandler();
131 if (current != this) {
132 current.endElement(namespaceURI, localName, qName);
133 }
134
135 }
136
137 }