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1   /*
2    * Redistribution and use of this software and associated documentation
3    * ("Software"), with or without modification, are permitted provided
4    * that the following conditions are met:
5    *
6    * 1. Redistributions of source code must retain copyright
7    *    statements and notices.  Redistributions must also contain a
8    *    copy of this document.
9    *
10   * 2. Redistributions in binary form must reproduce the
11   *    above copyright notice, this list of conditions and the
12   *    following disclaimer in the documentation and/or other
13   *    materials provided with the distribution.
14   *
15   * 3. The name "Exolab" must not be used to endorse or promote
16   *    products derived from this Software without prior written
17   *    permission of Intalio, Inc.  For written permission,
18   *    please contact info@exolab.org.
19   *
20   * 4. Products derived from this Software may not be called "Exolab"
21   *    nor may "Exolab" appear in their names without prior written
22   *    permission of Intalio, Inc. Exolab is a registered
23   *    trademark of Intalio, Inc.
24   *
25   * 5. Due credit should be given to the Exolab Project
26   *    (http://www.exolab.org/).
27   *
28   * THIS SOFTWARE IS PROVIDED BY INTALIO, INC. AND CONTRIBUTORS
29   * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
30   * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
31   * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
32   * INTALIO, INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
33   * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
34   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
35   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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37   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
38   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
39   * OF THE POSSIBILITY OF SUCH DAMAGE.
40   *
41   * Copyright 1999, 2000 (C) Intalio, Inc. All Rights Reserved.
42   *
43   * $Id$
44   */
45  package org.exolab.castor.xml.util;
46  
47  import org.w3c.dom.Document;
48  import org.w3c.dom.Element;
49  import org.w3c.dom.Node;
50  import org.w3c.dom.ProcessingInstruction;
51  import org.w3c.dom.Text;
52  import org.xml.sax.AttributeList;
53  import org.xml.sax.HandlerBase;
54  import org.xml.sax.SAXException;
55  
56  import java.util.Stack;
57  
58  /**
59   * A class for converting a SAX events to DOM nodes.
60   *
61   * @author <a href="mailto:andrew.fawcett@coda.com">Andrew Fawcett</a>
62   */
63  public class SAX2DOMHandler extends HandlerBase {
64      
65      private Node _node;
66      
67      private Stack<Element> _parents = new Stack<Element>();
68  
69      /**
70       * Creates new instance of {@link SAX2DOMHandler} class.
71       *
72       * @param node the DOM node to use
73       */
74      public SAX2DOMHandler(Node node) {
75          _node = node;
76      }
77  
78      @Override
79      public void startElement(final String name, final AttributeList attributes) {
80          Node parent = _parents.size() > 0 ? (Node) _parents.peek() : _node;
81          final Document document = getDocument(parent);
82  
83          Element element = document.createElement(name);
84          int length = attributes.getLength();
85          for (int i = 0; i < length; i++) {
86              element.setAttribute(attributes.getName(i), attributes.getValue(i));
87          }
88          parent.appendChild(element);
89          _parents.push(element);
90      }
91  
92      @Override
93      public void characters(final char[] chars, final int offset, final int length) {
94          String data = new String(chars, offset, length);
95          Node parent = (_parents.size() > 0) ? (Node) _parents.peek() : _node;
96          Node last = parent.getLastChild();
97          if ((last != null) && (last.getNodeType() == Node.TEXT_NODE)) {
98              ((Text) last).appendData(data);
99          } else {
100             Text text = parent.getOwnerDocument().createTextNode(data);
101             parent.appendChild(text);
102         }
103     }
104 
105     @Override
106     public void endElement(final String name) {
107         _parents.pop();
108     }
109 
110     @Override
111     public void processingInstruction(String target, String data) throws SAXException {
112         // adds the given processing instruction to the document root
113         Document document = getDocument(_node);
114         ProcessingInstruction instruction = document.createProcessingInstruction(target, data);
115         document.insertBefore(instruction, document.getFirstChild());
116     }
117     
118     /**
119      * Returns the owning {@link Document} for the given {@link Node}.
120      * @param node A given node.
121      * @return the owning {@link Document} for the give node.
122      */
123     private Document getDocument(Node node) {
124         Document document;
125         if (node instanceof Document) {
126             document = (Document) node;
127         } else {
128             document = node.getOwnerDocument();
129         }
130         return document;
131     }
132 }