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 * ItemHandler.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: ItemHandler.java,v 1.3.2.1 2005/10/25 21:36:10 mungady Exp $ 036 * 037 * Changes (from 21-Jun-2001) 038 * -------------------------- 039 * 23-Jan-2003 : Version 1 (DG); 040 * 041 */ 042 043 package org.jfree.data.xml; 044 045 import org.xml.sax.Attributes; 046 import org.xml.sax.SAXException; 047 import org.xml.sax.helpers.DefaultHandler; 048 049 /** 050 * A handler for reading key-value items. 051 */ 052 public class ItemHandler extends DefaultHandler implements DatasetTags { 053 054 /** The root handler. */ 055 private RootHandler root; 056 057 /** The parent handler (can be the same as root, but not always). */ 058 private DefaultHandler parent; 059 060 /** The key. */ 061 private Comparable key; 062 063 /** The value. */ 064 private Number value; 065 066 /** 067 * Creates a new item handler. 068 * 069 * @param root the root handler. 070 * @param parent the parent handler. 071 */ 072 public ItemHandler(RootHandler root, DefaultHandler parent) { 073 this.root = root; 074 this.parent = parent; 075 this.key = null; 076 this.value = null; 077 } 078 079 /** 080 * Returns the key that has been read by the handler, or <code>null</code>. 081 * 082 * @return The key. 083 */ 084 public Comparable getKey() { 085 return this.key; 086 } 087 088 /** 089 * Sets the key. 090 * 091 * @param key the key. 092 */ 093 public void setKey(Comparable key) { 094 this.key = key; 095 } 096 097 /** 098 * Returns the key that has been read by the handler, or <code>null</code>. 099 * 100 * @return The value. 101 */ 102 public Number getValue() { 103 return this.value; 104 } 105 106 /** 107 * Sets the value. 108 * 109 * @param value the value. 110 */ 111 public void setValue(Number value) { 112 this.value = value; 113 } 114 115 /** 116 * The start of an element. 117 * 118 * @param namespaceURI the namespace. 119 * @param localName the element name. 120 * @param qName the element name. 121 * @param atts the attributes. 122 * 123 * @throws SAXException for errors. 124 */ 125 public void startElement(String namespaceURI, 126 String localName, 127 String qName, 128 Attributes atts) throws SAXException { 129 130 if (qName.equals(ITEM_TAG)) { 131 KeyHandler subhandler = new KeyHandler(this.root, this); 132 this.root.pushSubHandler(subhandler); 133 } 134 else if (qName.equals(VALUE_TAG)) { 135 ValueHandler subhandler = new ValueHandler(this.root, this); 136 this.root.pushSubHandler(subhandler); 137 } 138 else { 139 throw new SAXException( 140 "Expected <Item> or <Value>...found " + qName 141 ); 142 } 143 144 } 145 146 /** 147 * The end of an element. 148 * 149 * @param namespaceURI the namespace. 150 * @param localName the element name. 151 * @param qName the element name. 152 */ 153 public void endElement(String namespaceURI, 154 String localName, 155 String qName) { 156 157 if (this.parent instanceof PieDatasetHandler) { 158 PieDatasetHandler handler = (PieDatasetHandler) this.parent; 159 handler.addItem(this.key, this.value); 160 this.root.popSubHandler(); 161 } 162 else if (this.parent instanceof CategorySeriesHandler) { 163 CategorySeriesHandler handler = (CategorySeriesHandler) this.parent; 164 handler.addItem(this.key, this.value); 165 this.root.popSubHandler(); 166 } 167 168 } 169 170 }