content: /* ===========================================================
   * JFreeChart : a free chart library for the Java(tm) platform
   * ===========================================================
   *
   * (C) Copyright 2000-2008, by Object Refinery Limited and Contributors.
   *
   * Project Info:  http://www.jfree.org/jfreechart/index.html
   *
   * This library is free software; you can redistribute it and/or modify it
   * under the terms of the GNU Lesser General Public License as published by
   * the Free Software Foundation; either version 2.1 of the License, or
   * (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
   * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
   * License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
   * USA.
   *
   * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
   * in the United States and other countries.]
   *
   * ----------------
   * ItemHandler.java
   * ----------------
   * (C) Copyright 2003-2008, by Object Refinery Limited and Contributors.
   *
   * Original Author:  David Gilbert (for Object Refinery Limited);
   * Contributor(s):   -;
   *
   * Changes
   * -------
   * 23-Jan-2003 : Version 1 (DG);
   *
   */
  
  package org.jfree.data.xml;
  
  import org.xml.sax.Attributes;
  import org.xml.sax.SAXException;
  import org.xml.sax.helpers.DefaultHandler;
  
  /**
   * A handler for reading key-value items.
   */
  public class ItemHandler extends DefaultHandler implements DatasetTags {
  
      /** The root handler. */
      private RootHandler root;
  
      /** The parent handler (can be the same as root, but not always). */
      private DefaultHandler parent;
  
      /** The key. */
      private Comparable key;
  
      /** The value. */
      private Number value;
  
      /**
       * Creates a new item handler.
       *
       * @param root  the root handler.
       * @param parent  the parent handler.
       */
      public ItemHandler(RootHandler root, DefaultHandler parent) {
          this.root = root;
          this.parent = parent;
          this.key = null;
          this.value = null;
      }
  
      /**
       * Returns the key that has been read by the handler, or <code>null</code>.
       *
       * @return The key.
       */
      public Comparable getKey() {
          return this.key;
      }
  
      /**
       * Sets the key.
       *
       * @param key  the key.
       */
      public void setKey(Comparable key) {
          this.key = key;
      }
  
      /**
       * Returns the key that has been read by the handler, or <code>null</code>.
       *
       * @return The value.
       */
      public Number getValue() {
          return this.value;
      }
  
      /**
       * Sets the value.
       *
       * @param value  the value.
       */
      public void setValue(Number value) {
          this.value = value;
      }
  
      /**
       * The start of an element.
       *
       * @param namespaceURI  the namespace.
       * @param localName  the element name.
       * @param qName  the element name.
       * @param atts  the attributes.
       *
       * @throws SAXException for errors.
       */
      public void startElement(String namespaceURI,
                               String localName,
                               String qName,
                               Attributes atts) throws SAXException {
  
          if (qName.equals(ITEM_TAG)) {
              KeyHandler subhandler = new KeyHandler(this.root, this);
              this.root.pushSubHandler(subhandler);
          }
          else if (qName.equals(VALUE_TAG)) {
              ValueHandler subhandler = new ValueHandler(this.root, this);
              this.root.pushSubHandler(subhandler);
          }
          else {
              throw new SAXException(
                  "Expected <Item> or <Value>...found " + qName
              );
          }
  
      }
  
      /**
       * The end of an element.
       *
       * @param namespaceURI  the namespace.
       * @param localName  the element name.
       * @param qName  the element name.
       */
      public void endElement(String namespaceURI,
                             String localName,
                             String qName) {
  
          if (this.parent instanceof PieDatasetHandler) {
              PieDatasetHandler handler = (PieDatasetHandler) this.parent;
              handler.addItem(this.key, this.value);
              this.root.popSubHandler();
          }
          else if (this.parent instanceof CategorySeriesHandler) {
              CategorySeriesHandler handler = (CategorySeriesHandler) this.parent;
              handler.addItem(this.key, this.value);
              this.root.popSubHandler();
          }
  
      }
  
  }
  