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1   /*
2    * Redistribution and use of this software and associated documentation ("Software"), with or
3    * without modification, are permitted provided that the following conditions are met:
4    *
5    * 1. Redistributions of source code must retain copyright statements and notices. Redistributions
6    * must also contain a copy of this document.
7    *
8    * 2. Redistributions in binary form must reproduce the above copyright notice, this list of
9    * conditions and the following disclaimer in the documentation and/or other materials provided with
10   * the distribution.
11   *
12   * 3. The name "Exolab" must not be used to endorse or promote products derived from this Software
13   * without prior written permission of Intalio, Inc. For written permission, please contact
14   * info@exolab.org.
15   *
16   * 4. Products derived from this Software may not be called "Exolab" nor may "Exolab" appear in
17   * their names without prior written permission of Intalio, Inc. Exolab is a registered trademark of
18   * Intalio, Inc.
19   *
20   * 5. Due credit should be given to the Exolab Project (http://www.exolab.org/).
21   *
22   * THIS SOFTWARE IS PROVIDED BY INTALIO, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR
23   * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
24   * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTALIO, INC. OR ITS
25   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
28   * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
29   * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30   *
31   * Copyright 2004 (C) Intalio, Inc. All Rights Reserved.
32   *
33   *
34   */
35  package org.exolab.castor.xml.util;
36  
37  import org.exolab.castor.xml.Namespaces;
38  import org.exolab.castor.xml.NamespacesStack;
39  import org.xml.sax.Attributes;
40  import org.xml.sax.ContentHandler;
41  import org.xml.sax.DocumentHandler;
42  import org.xml.sax.Locator;
43  import org.xml.sax.SAXException;
44  import org.xml.sax.helpers.AttributeListImpl;
45  
46  /**
47   * A ContentHandler implementation that wraps a DocumentHandler. This ContentHandler was written for
48   * the Marshaller and expects that QNames are non-null in calls to startElement and endElement
49   * methods as well as inside the Attributes list.
50   *
51   * @author <a href="mailto:kvisco@intalio.com">Keith Visco</a>
52   * @version $Revision$ $Date: 2004-09-10 12:15:10 -0600 (Fri, 10 Sep 2004) $
53   */
54  public class DocumentHandlerAdapter implements ContentHandler {
55  
56    private static final String CDATA = "CDATA";
57  
58    private DocumentHandler _handler = null;
59  
60    /**
61     * Represents the namespaces stack.
62     */
63    private NamespacesStack namespacesStack = null;
64  
65    private boolean _createNamespaceScope = true;
66  
67    /**
68     * Creates a new DocumentHandlerAdapter
69     *
70     * @param handler the DocumentHandler to wrap (non-null).
71     */
72    public DocumentHandlerAdapter(DocumentHandler handler) {
73      if (handler == null) {
74        throw new IllegalArgumentException("The argument 'handler' must not be null.");
75      }
76      _handler = handler;
77      namespacesStack = new NamespacesStack();
78    }
79  
80    /**
81     * @see org.xml.sax.ContentHandler#characters(char[], int, int)
82     */
83    public void characters(char[] chars, int start, int length) throws SAXException {
84      _handler.characters(chars, start, length);
85    }
86  
87    /**
88     * @see org.xml.sax.ContentHandler#endDocument()
89     */
90    public void endDocument() throws SAXException {
91      _handler.endDocument();
92    }
93  
94    /**
95     * @see org.xml.sax.ContentHandler#endElement(java.lang.String, java.lang.String,
96     *      java.lang.String)
97     */
98    public void endElement(String uri, String localName, String qName) throws SAXException {
99      _handler.endElement(qName);
100     namespacesStack.removeNamespaceScope();
101   }
102 
103   /**
104    * @see org.xml.sax.ContentHandler#endPrefixMapping(java.lang.String)
105    */
106   public void endPrefixMapping(String prefix) throws SAXException {
107     // -- do nothing here, this is handled in endElement
108     // -- by simply removing the current namespace scope
109 
110   }
111 
112   /**
113    * @see org.xml.sax.ContentHandler#ignorableWhitespace(char[], int, int)
114    */
115   public void ignorableWhitespace(char[] chars, int start, int length) throws SAXException {
116     _handler.ignorableWhitespace(chars, start, length);
117   }
118 
119   /**
120    * @see org.xml.sax.ContentHandler#processingInstruction(java.lang.String, java.lang.String)
121    */
122   public void processingInstruction(String target, String data) throws SAXException {
123     _handler.processingInstruction(target, data);
124   }
125 
126   /**
127    * @see org.xml.sax.ContentHandler#setDocumentLocator(org.xml.sax.Locator)
128    */
129   public void setDocumentLocator(Locator locator) {
130     _handler.setDocumentLocator(locator);
131   }
132 
133   /**
134    * @see org.xml.sax.ContentHandler#skippedEntity(java.lang.String)
135    */
136   public void skippedEntity(String arg0) throws SAXException {
137     // -- do nothing
138   }
139 
140   /**
141    * @see org.xml.sax.ContentHandler#startDocument()
142    */
143   public void startDocument() throws SAXException {
144     _handler.startDocument();
145   }
146 
147   /**
148    * @see org.xml.sax.ContentHandler#startElement(java.lang.String, java.lang.String,
149    *      java.lang.String, org.xml.sax.Attributes)
150    */
151   public void startElement(String uri, String localName, String qName, Attributes atts)
152       throws SAXException {
153     AttributeListImpl attList = new AttributeListImpl();
154 
155     // -- Create a new namespace scope if necessary and
156     // -- make sure the flag is reset to true
157     if (_createNamespaceScope) {
158       // -- no current namespaces, but we create a new scope
159       // -- to make things easier in the endElement method
160       namespacesStack.addNewNamespaceScope();
161     } else {
162       _createNamespaceScope = true;
163       namespacesStack.declareAsAttributes(attList, true);
164     }
165 
166     // -- copy Attributes to AttributeList
167     for (int i = 0; i < atts.getLength(); i++) {
168       attList.addAttribute(atts.getQName(i), CDATA, atts.getValue(i));
169     }
170 
171     _handler.startElement(qName, attList);
172 
173   }
174 
175   /**
176    * @see org.xml.sax.ContentHandler#startPrefixMapping(java.lang.String, java.lang.String)
177    */
178   public void startPrefixMapping(String prefix, String uri) throws SAXException {
179     if (_createNamespaceScope) {
180       namespacesStack.addNewNamespaceScope();
181       _createNamespaceScope = false;
182     }
183 
184     namespacesStack.addNamespace(prefix, uri);
185   }
186 }