Source for org.jfree.data.xml.PieDatasetHandler

   1: /* ===========================================================
   2:  * JFreeChart : a free chart library for the Java(tm) platform
   3:  * ===========================================================
   4:  *
   5:  * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
   6:  *
   7:  * Project Info:  http://www.jfree.org/jfreechart/index.html
   8:  *
   9:  * This library is free software; you can redistribute it and/or modify it 
  10:  * under the terms of the GNU Lesser General Public License as published by 
  11:  * the Free Software Foundation; either version 2.1 of the License, or 
  12:  * (at your option) any later version.
  13:  *
  14:  * This library is distributed in the hope that it will be useful, but 
  15:  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
  16:  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
  17:  * License for more details.
  18:  *
  19:  * You should have received a copy of the GNU Lesser General Public
  20:  * License along with this library; if not, write to the Free Software
  21:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
  22:  * USA.  
  23:  *
  24:  * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
  25:  * in the United States and other countries.]
  26:  *
  27:  * ----------------------
  28:  * PieDatasetHandler.java
  29:  * ----------------------
  30:  * (C) Copyright 2003-2005, by Object Refinery Limited and Contributors.
  31:  *
  32:  * Original Author:  David Gilbert (for Object Refinery Limited);
  33:  * Contributor(s):   -;
  34:  *
  35:  * $Id: PieDatasetHandler.java,v 1.3.2.1 2005/10/25 21:36:10 mungady Exp $
  36:  *
  37:  * Changes (from 21-Jun-2001)
  38:  * --------------------------
  39:  * 23-Jan-2003 : Version 1 (DG);
  40:  *
  41:  */
  42: 
  43: package org.jfree.data.xml;
  44: 
  45: import org.jfree.data.general.DefaultPieDataset;
  46: import org.jfree.data.general.PieDataset;
  47: import org.xml.sax.Attributes;
  48: import org.xml.sax.SAXException;
  49: import org.xml.sax.helpers.DefaultHandler;
  50: 
  51: /**
  52:  * A SAX handler for reading a {@link PieDataset} from an XML file.
  53:  */
  54: public class PieDatasetHandler extends RootHandler implements DatasetTags {
  55: 
  56:     /** The pie dataset under construction. */
  57:     private DefaultPieDataset dataset;
  58: 
  59:     /**
  60:      * Default constructor.
  61:      */
  62:     public PieDatasetHandler() {
  63:         this.dataset = null;
  64:     }
  65: 
  66:     /**
  67:      * Returns the dataset.
  68:      *
  69:      * @return The dataset.
  70:      */
  71:     public PieDataset getDataset() {
  72:         return this.dataset;
  73:     }
  74: 
  75:     /**
  76:      * Adds an item to the dataset under construction.
  77:      *
  78:      * @param key  the key.
  79:      * @param value  the value.
  80:      */
  81:     public void addItem(Comparable key, Number value) {
  82:         this.dataset.setValue(key, value);
  83:     }
  84: 
  85:     /**
  86:      * Starts an element.
  87:      *
  88:      * @param namespaceURI  the namespace.
  89:      * @param localName  the element name.
  90:      * @param qName  the element name.
  91:      * @param atts  the element attributes.
  92:      *
  93:      * @throws SAXException for errors.
  94:      */
  95:     public void startElement(String namespaceURI,
  96:                              String localName,
  97:                              String qName,
  98:                              Attributes atts) throws SAXException {
  99: 
 100:         DefaultHandler current = getCurrentHandler();
 101:         if (current != this) {
 102:             current.startElement(namespaceURI, localName, qName, atts);
 103:         }
 104:         else if (qName.equals(PIEDATASET_TAG)) {
 105:             this.dataset = new DefaultPieDataset();
 106:         }
 107:         else if (qName.equals(ITEM_TAG)) {
 108:             ItemHandler subhandler = new ItemHandler(this, this);
 109:             getSubHandlers().push(subhandler);
 110:             subhandler.startElement(namespaceURI, localName, qName, atts);
 111:         }
 112: 
 113:     }
 114: 
 115:     /**
 116:      * The end of an element.
 117:      *
 118:      * @param namespaceURI  the namespace.
 119:      * @param localName  the element name.
 120:      * @param qName  the element name.
 121:      *
 122:      * @throws SAXException for errors.
 123:      */
 124:     public void endElement(String namespaceURI,
 125:                            String localName,
 126:                            String qName) throws SAXException {
 127: 
 128:         DefaultHandler current = getCurrentHandler();
 129:         if (current != this) {
 130:             current.endElement(namespaceURI, localName, qName);
 131:         }
 132: 
 133:     }
 134: 
 135: }