001/*
002 * Copyright 2001 (C) MetaStuff, Ltd. All Rights Reserved.
003 * 
004 * This software is open source. 
005 * See the bottom of this file for the licence.
006 * 
007 * $Id: BeanDocumentFactory.java,v 1.8 2001/08/09 13:35:14 jstrachan Exp $
008 */
009
010package org.dom4j.bean;
011
012import java.util.Map;
013
014import org.dom4j.DocumentFactory;
015import org.dom4j.Attribute;
016import org.dom4j.Element;
017import org.dom4j.QName;
018import org.dom4j.tree.DefaultAttribute;
019import org.dom4j.tree.DefaultElement;
020
021import org.xml.sax.Attributes;
022
023/** <p><code>BeanDocumentFactory</code> is a factory of DOM4J objects
024  * which may be BeanElements which are backed by JavaBeans 
025  * and their properties. </p>
026  *
027  * <p>The tree built allows full XPath expressions from anywhere on the 
028  * tree.</p>
029  *
030  * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
031  * @version $Revision: 1.8 $
032  */
033public class BeanDocumentFactory extends DocumentFactory {
034
035    /** The Singleton instance */
036    private static BeanDocumentFactory singleton = new BeanDocumentFactory();
037
038    /** <p>Access to the singleton instance of this factory.</p>
039      *
040      * @return the default singleon instance
041      */
042    public static DocumentFactory getInstance() {
043        return singleton;
044    }
045    
046    
047    // Factory methods
048    
049    public Element createElement(QName qname) {
050        Object bean = createBean( qname );
051        if ( bean == null ) {
052            return new BeanElement(qname);
053        }
054        else {
055            return new BeanElement(qname, bean);
056        }
057    }
058    
059    public Element createElement(QName qname, Attributes attributes) {
060        Object bean = createBean( qname, attributes );
061        if ( bean == null ) {
062            return new BeanElement(qname);
063        }
064        else {
065            return new BeanElement(qname, bean);
066        }
067    }
068    
069    public Attribute createAttribute(Element owner, QName qname, String value) {
070        return new DefaultAttribute(qname, value);
071    }
072    
073    
074    // Implementation methods
075    
076    protected Object createBean( QName qname ) {
077        return null;
078    }
079    
080    protected Object createBean( QName qname, Attributes attributes ) {
081        String value = attributes.getValue( "class" );
082        if ( value != null ) {
083            try {
084                Class beanClass = Class.forName( 
085                    value, 
086                    true, 
087                    BeanDocumentFactory.class.getClassLoader() 
088                );
089                return beanClass.newInstance();
090            }
091            catch (Exception e) {
092                handleException(e);
093            }
094        }
095        return null;
096    }
097    
098    protected void handleException(Exception e) {
099        // ignore introspection exceptions
100        System.out.println( "#### Warning: couldn't create bean: " + e );
101    }
102}
103
104
105
106
107/*
108 * Redistribution and use of this software and associated documentation
109 * ("Software"), with or without modification, are permitted provided
110 * that the following conditions are met:
111 *
112 * 1. Redistributions of source code must retain copyright
113 *    statements and notices.  Redistributions must also contain a
114 *    copy of this document.
115 *
116 * 2. Redistributions in binary form must reproduce the
117 *    above copyright notice, this list of conditions and the
118 *    following disclaimer in the documentation and/or other
119 *    materials provided with the distribution.
120 *
121 * 3. The name "DOM4J" must not be used to endorse or promote
122 *    products derived from this Software without prior written
123 *    permission of MetaStuff, Ltd.  For written permission,
124 *    please contact dom4j-info@metastuff.com.
125 *
126 * 4. Products derived from this Software may not be called "DOM4J"
127 *    nor may "DOM4J" appear in their names without prior written
128 *    permission of MetaStuff, Ltd. DOM4J is a registered
129 *    trademark of MetaStuff, Ltd.
130 *
131 * 5. Due credit should be given to the DOM4J Project
132 *    (http://dom4j.org/).
133 *
134 * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS
135 * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
136 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
137 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
138 * METASTUFF, LTD. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
139 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
140 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
141 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
142 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
143 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
144 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
145 * OF THE POSSIBILITY OF SUCH DAMAGE.
146 *
147 * Copyright 2001 (C) MetaStuff, Ltd. All Rights Reserved.
148 *
149 * $Id: BeanDocumentFactory.java,v 1.8 2001/08/09 13:35:14 jstrachan Exp $
150 */