Source for org.jfree.data.xml.PieDatasetHandler

   1: /* ===========================================================
   2:  * JFreeChart : a free chart library for the Java(tm) platform
   3:  * ===========================================================
   4:  *
   5:  * (C) Copyright 2000-2007, 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 2003-2007, by Object Refinery Limited and Contributors.
  31:  *
  32:  * Original Author:  David Gilbert (for Object Refinery Limited);
  33:  * Contributor(s):   -;
  34:  *
  35:  * Changes
  36:  * -------
  37:  * 23-Jan-2003 : Version 1 (DG);
  38:  *
  39:  */
  40: 
  41: package org.jfree.data.xml;
  42: 
  43: import org.jfree.data.general.DefaultPieDataset;
  44: import org.jfree.data.general.PieDataset;
  45: import org.xml.sax.Attributes;
  46: import org.xml.sax.SAXException;
  47: import org.xml.sax.helpers.DefaultHandler;
  48: 
  49: /**
  50:  * A SAX handler for reading a {@link PieDataset} from an XML file.
  51:  */
  52: public class PieDatasetHandler extends RootHandler implements DatasetTags {
  53: 
  54:     /** The pie dataset under construction. */
  55:     private DefaultPieDataset dataset;
  56: 
  57:     /**
  58:      * Default constructor.
  59:      */
  60:     public PieDatasetHandler() {
  61:         this.dataset = null;
  62:     }
  63: 
  64:     /**
  65:      * Returns the dataset.
  66:      *
  67:      * @return The dataset.
  68:      */
  69:     public PieDataset getDataset() {
  70:         return this.dataset;
  71:     }
  72: 
  73:     /**
  74:      * Adds an item to the dataset under construction.
  75:      *
  76:      * @param key  the key.
  77:      * @param value  the value.
  78:      */
  79:     public void addItem(Comparable key, Number value) {
  80:         this.dataset.setValue(key, value);
  81:     }
  82: 
  83:     /**
  84:      * Starts an element.
  85:      *
  86:      * @param namespaceURI  the namespace.
  87:      * @param localName  the element name.
  88:      * @param qName  the element name.
  89:      * @param atts  the element attributes.
  90:      *
  91:      * @throws SAXException for errors.
  92:      */
  93:     public void startElement(String namespaceURI,
  94:                              String localName,
  95:                              String qName,
  96:                              Attributes atts) throws SAXException {
  97: 
  98:         DefaultHandler current = getCurrentHandler();
  99:         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: }