001/* ========================================================================
002 * JCommon : a free general purpose class 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/jcommon/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 * XmlReadHandler.java
029 * -------------------
030 * (C)opyright 2003, 2004, by Thomas Morgner and Contributors.
031 *
032 * Original Author:  Thomas Morgner;
033 * Contributor(s):   David Gilbert (for Object Refinery Limited);
034 *
035 * $Id: XmlReadHandler.java,v 1.3 2005/10/18 13:32:52 mungady Exp $
036 *
037 * Changes (from 25-Nov-2003)
038 * --------------------------
039 * 25-Nov-2003 : Added Javadocs (DG);
040 *  
041 */
042
043package org.jfree.xml.parser;
044
045import org.xml.sax.Attributes;
046import org.xml.sax.SAXException;
047
048/**
049 * A handler for reading an XML element.
050 */
051public interface XmlReadHandler {
052    
053    /**
054     * This method is called at the start of an element.
055     * 
056     * @param tagName  the tag name.
057     * @param attrs  the attributes.
058     * 
059     * @throws SAXException if there is a parsing error.
060     * @throws XmlReaderException if there is a reader error.
061     */
062    public void startElement(String tagName, Attributes attrs)
063        throws SAXException, XmlReaderException;
064    
065    /**
066     * This method is called to process the character data between element tags.
067     * 
068     * @param ch  the character buffer.
069     * @param start  the start index.
070     * @param length  the length.
071     * 
072     * @throws SAXException if there is a parsing error.
073     */
074    public void characters(char[] ch, int start, int length)
075        throws SAXException;
076    
077    /**
078     * This method is called at the end of an element.
079     * 
080     * @param tagName  the tag name.
081     * 
082     * @throws SAXException if there is a parsing error.
083     * @throws XmlReaderException if there is a reader error.
084     */
085    public void endElement(String tagName)
086        throws SAXException, XmlReaderException;
087    
088    /**
089     * Returns the object for this element or null, if this element does
090     * not create an object.
091     * 
092     * @return the object.
093     * 
094     * @throws XmlReaderException if there is a parsing error.
095     */
096    public Object getObject() throws XmlReaderException;
097    
098    /**
099     * Initialise.
100     * 
101     * @param rootHandler  the root handler.
102     * @param tagName  the tag name.
103     */
104    public void init(RootXmlReadHandler rootHandler, String tagName);
105
106}