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1   /*
2    * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
3    *
4    * This software is open source.
5    * See the bottom of this file for the licence.
6    */
7   
8   package org.dom4j.bean;
9   
10  import org.dom4j.Attribute;
11  import org.dom4j.DocumentFactory;
12  import org.dom4j.Element;
13  import org.dom4j.QName;
14  import org.dom4j.tree.DefaultAttribute;
15  
16  import org.xml.sax.Attributes;
17  
18  /***
19   * <p>
20   * <code>BeanDocumentFactory</code> is a factory of DOM4J objects which may be
21   * BeanElements which are backed by JavaBeans and their properties.
22   * </p>
23   * 
24   * <p>
25   * The tree built allows full XPath expressions from anywhere on the tree.
26   * </p>
27   * 
28   * @author <a href="mailto:jstrachan@apache.org">James Strachan </a>
29   * @version $Revision: 1.14 $
30   */
31  public class BeanDocumentFactory extends DocumentFactory {
32      /*** The Singleton instance */
33      private static BeanDocumentFactory singleton = new BeanDocumentFactory();
34  
35      /***
36       * <p>
37       * Access to the singleton instance of this factory.
38       * </p>
39       * 
40       * @return the default singleon instance
41       */
42      public static DocumentFactory getInstance() {
43          return singleton;
44      }
45  
46      // Factory methods
47      public Element createElement(QName qname) {
48          Object bean = createBean(qname);
49  
50          if (bean == null) {
51              return new BeanElement(qname);
52          } else {
53              return new BeanElement(qname, bean);
54          }
55      }
56  
57      public Element createElement(QName qname, Attributes attributes) {
58          Object bean = createBean(qname, attributes);
59  
60          if (bean == null) {
61              return new BeanElement(qname);
62          } else {
63              return new BeanElement(qname, bean);
64          }
65      }
66  
67      public Attribute createAttribute(Element owner, QName qname, String value) {
68          return new DefaultAttribute(qname, value);
69      }
70  
71      // Implementation methods
72      protected Object createBean(QName qname) {
73          return null;
74      }
75  
76      protected Object createBean(QName qname, Attributes attributes) {
77          String value = attributes.getValue("class");
78  
79          if (value != null) {
80              try {
81                  Class beanClass = Class.forName(value, true,
82                          BeanDocumentFactory.class.getClassLoader());
83  
84                  return beanClass.newInstance();
85              } catch (Exception e) {
86                  handleException(e);
87              }
88          }
89  
90          return null;
91      }
92  
93      protected void handleException(Exception e) {
94          // ignore introspection exceptions
95          System.out.println("#### Warning: couldn't create bean: " + e);
96      }
97  }
98  
99  /*
100  * Redistribution and use of this software and associated documentation
101  * ("Software"), with or without modification, are permitted provided that the
102  * following conditions are met:
103  * 
104  * 1. Redistributions of source code must retain copyright statements and
105  * notices. Redistributions must also contain a copy of this document.
106  * 
107  * 2. Redistributions in binary form must reproduce the above copyright notice,
108  * this list of conditions and the following disclaimer in the documentation
109  * and/or other materials provided with the distribution.
110  * 
111  * 3. The name "DOM4J" must not be used to endorse or promote products derived
112  * from this Software without prior written permission of MetaStuff, Ltd. For
113  * written permission, please contact dom4j-info@metastuff.com.
114  * 
115  * 4. Products derived from this Software may not be called "DOM4J" nor may
116  * "DOM4J" appear in their names without prior written permission of MetaStuff,
117  * Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
118  * 
119  * 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
120  * 
121  * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND
122  * ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
123  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
124  * ARE DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE
125  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
126  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
127  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
128  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
129  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
130  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
131  * POSSIBILITY OF SUCH DAMAGE.
132  * 
133  * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
134  */