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 * PieDatasetHandler.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.general.DefaultPieDataset;
044 import org.jfree.data.general.PieDataset;
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 PieDataset} from an XML file.
051 */
052 public class PieDatasetHandler extends RootHandler implements DatasetTags {
053
054 /** The pie dataset under construction. */
055 private DefaultPieDataset dataset;
056
057 /**
058 * Default constructor.
059 */
060 public PieDatasetHandler() {
061 this.dataset = null;
062 }
063
064 /**
065 * Returns the dataset.
066 *
067 * @return The dataset.
068 */
069 public PieDataset getDataset() {
070 return this.dataset;
071 }
072
073 /**
074 * Adds an item to the dataset under construction.
075 *
076 * @param key the key.
077 * @param value the value.
078 */
079 public void addItem(Comparable key, Number value) {
080 this.dataset.setValue(key, value);
081 }
082
083 /**
084 * Starts an element.
085 *
086 * @param namespaceURI the namespace.
087 * @param localName the element name.
088 * @param qName the element name.
089 * @param atts the element attributes.
090 *
091 * @throws SAXException for errors.
092 */
093 public void startElement(String namespaceURI,
094 String localName,
095 String qName,
096 Attributes atts) throws SAXException {
097
098 DefaultHandler current = getCurrentHandler();
099 if (current != this) {
100 current.startElement(namespaceURI, localName, qName, atts);
101 }
102 else if (qName.equals(PIEDATASET_TAG)) {
103 this.dataset = new DefaultPieDataset();
104 }
105 else if (qName.equals(ITEM_TAG)) {
106 ItemHandler subhandler = new ItemHandler(this, this);
107 getSubHandlers().push(subhandler);
108 subhandler.startElement(namespaceURI, localName, qName, atts);
109 }
110
111 }
112
113 /**
114 * The end of an element.
115 *
116 * @param namespaceURI the namespace.
117 * @param localName the element name.
118 * @param qName the element name.
119 *
120 * @throws SAXException for errors.
121 */
122 public void endElement(String namespaceURI,
123 String localName,
124 String qName) throws SAXException {
125
126 DefaultHandler current = getCurrentHandler();
127 if (current != this) {
128 current.endElement(namespaceURI, localName, qName);
129 }
130
131 }
132
133 }