    001/* ===========================================================
    002 * JFreeChart : a free chart library for the Java(tm) platform
    003 * ===========================================================
    004 *
    005 * (C) Copyright 2000-2011, 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 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
    025 * Other names may be trademarks of their respective owners.]
    026 *
    027 * ----------------
    028 * ItemHandler.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
    041package org.jfree.data.xml;
    042
    043import org.xml.sax.Attributes;
    044import org.xml.sax.SAXException;
    045import org.xml.sax.helpers.DefaultHandler;
    046
    047/**
    048 * A handler for reading key-value items.
    049 */
    050public class ItemHandler extends DefaultHandler implements DatasetTags {
    051
    052    /** The root handler. */
    053    private RootHandler root;
    054
    055    /** The parent handler (can be the same as root, but not always). */
    056    private DefaultHandler parent;
    057
    058    /** The key. */
    059    private Comparable key;
    060
    061    /** The value. */
    062    private Number value;
    063
    064    /**
    065     * Creates a new item handler.
    066     *
    067     * @param root  the root handler.
    068     * @param parent  the parent handler.
    069     */
    070    public ItemHandler(RootHandler root, DefaultHandler parent) {
    071        this.root = root;
    072        this.parent = parent;
    073        this.key = null;
    074        this.value = null;
    075    }
    076
    077    /**
    078     * Returns the key that has been read by the handler, or <code>null</code>.
    079     *
    080     * @return The key.
    081     */
    082    public Comparable getKey() {
    083        return this.key;
    084    }
    085
    086    /**
    087     * Sets the key.
    088     *
    089     * @param key  the key.
    090     */
    091    public void setKey(Comparable key) {
    092        this.key = key;
    093    }
    094
    095    /**
    096     * Returns the key that has been read by the handler, or <code>null</code>.
    097     *
    098     * @return The value.
    099     */
    100    public Number getValue() {
    101        return this.value;
    102    }
    103
    104    /**
    105     * Sets the value.
    106     *
    107     * @param value  the value.
    108     */
    109    public void setValue(Number value) {
    110        this.value = value;
    111    }
    112
    113    /**
    114     * The start of an element.
    115     *
    116     * @param namespaceURI  the namespace.
    117     * @param localName  the element name.
    118     * @param qName  the element name.
    119     * @param atts  the attributes.
    120     *
    121     * @throws SAXException for errors.
    122     */
    123    public void startElement(String namespaceURI,
    124                             String localName,
    125                             String qName,
    126                             Attributes atts) throws SAXException {
    127
    128        if (qName.equals(ITEM_TAG)) {
    129            KeyHandler subhandler = new KeyHandler(this.root, this);
    130            this.root.pushSubHandler(subhandler);
    131        }
    132        else if (qName.equals(VALUE_TAG)) {
    133            ValueHandler subhandler = new ValueHandler(this.root, this);
    134            this.root.pushSubHandler(subhandler);
    135        }
    136        else {
    137            throw new SAXException(
    138                "Expected <Item> or <Value>...found " + qName
    139            );
    140        }
    141
    142    }
    143
    144    /**
    145     * The end of an element.
    146     *
    147     * @param namespaceURI  the namespace.
    148     * @param localName  the element name.
    149     * @param qName  the element name.
    150     */
    151    public void endElement(String namespaceURI,
    152                           String localName,
    153                           String qName) {
    154
    155        if (this.parent instanceof PieDatasetHandler) {
    156            PieDatasetHandler handler = (PieDatasetHandler) this.parent;
    157            handler.addItem(this.key, this.value);
    158            this.root.popSubHandler();
    159        }
    160        else if (this.parent instanceof CategorySeriesHandler) {
    161            CategorySeriesHandler handler = (CategorySeriesHandler) this.parent;
    162            handler.addItem(this.key, this.value);
    163            this.root.popSubHandler();
    164        }
    165
    166    }
    167
    168}