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Java > Open Source Codes > org > dom4j > io > SAXValidator


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.io;
9
10 import java.io.IOException JavaDoc;
11
12 import org.dom4j.Document;
13
14 import org.xml.sax.ContentHandler JavaDoc;
15 import org.xml.sax.ErrorHandler JavaDoc;
16 import org.xml.sax.SAXException JavaDoc;
17 import org.xml.sax.XMLReader JavaDoc;
18 import org.xml.sax.helpers.DefaultHandler JavaDoc;
19
20 /**
21  * <p>
22  * <code>SAXValidator</code> validates an XML document by writing the document
23  * to a text buffer and parsing it with a validating SAX parser. This could be
24  * implemented much more efficiently by validating against the dom4j object
25  * model directly but at least allows the reuse of existing SAX based validating
26  * parsers.
27  * </p>
28  *
29  * @author <a HREF="mailto:james.strachan@metastuff.com">James Strachan </a>
30  * @version $Revision: 1.10 $
31  */
32 public class SAXValidator {
33     /** <code>XMLReader</code> used to parse the SAX events */
34     private XMLReader JavaDoc xmlReader;
35
36     /** ErrorHandler class to use */
37     private ErrorHandler JavaDoc errorHandler;
38
39     public SAXValidator() {
40     }
41
42     public SAXValidator(XMLReader JavaDoc xmlReader) {
43         this.xmlReader = xmlReader;
44     }
45
46     /**
47      * Validates the given <code>Document</code> by writing it to a validating
48      * SAX Parser.
49      *
50      * @param document
51      * is the Document to validate
52      *
53      * @throws SAXException
54      * if a validation error occurs
55      * @throws RuntimeException
56      * DOCUMENT ME!
57      */
58     public void validate(Document document) throws SAXException JavaDoc {
59         if (document != null) {
60             XMLReader JavaDoc reader = getXMLReader();
61
62             if (errorHandler != null) {
63                 reader.setErrorHandler(errorHandler);
64             }
65
66             try {
67                 reader.parse(new DocumentInputSource(document));
68             } catch (IOException JavaDoc e) {
69                 throw new RuntimeException JavaDoc("Caught and exception that should "
70                         + "never happen: " + e);
71             }
72         }
73     }
74
75     // Properties
76 // -------------------------------------------------------------------------
77
78     /**
79      * DOCUMENT ME!
80      *
81      * @return the <code>XMLReader</code> used to parse SAX events
82      *
83      * @throws SAXException
84      * DOCUMENT ME!
85      */
86     public XMLReader JavaDoc getXMLReader() throws SAXException JavaDoc {
87         if (xmlReader == null) {
88             xmlReader = createXMLReader();
89             configureReader();
90         }
91
92         return xmlReader;
93     }
94
95     /**
96      * Sets the <code>XMLReader</code> used to parse SAX events
97      *
98      * @param reader
99      * is the <code>XMLReader</code> to parse SAX events
100      *
101      * @throws SAXException
102      * DOCUMENT ME!
103      */
104     public void setXMLReader(XMLReader JavaDoc reader) throws SAXException JavaDoc {
105         this.xmlReader = reader;
106         configureReader();
107     }
108
109     /**
110      * DOCUMENT ME!
111      *
112      * @return the <code>ErrorHandler</code> used by SAX
113      */
114     public ErrorHandler JavaDoc getErrorHandler() {
115         return errorHandler;
116     }
117
118     /**
119      * Sets the <code>ErrorHandler</code> used by the SAX
120      * <code>XMLReader</code>.
121      *
122      * @param errorHandler
123      * is the <code>ErrorHandler</code> used by SAX
124      */
125     public void setErrorHandler(ErrorHandler JavaDoc errorHandler) {
126         this.errorHandler = errorHandler;
127     }
128
129     // Implementation methods
130 // -------------------------------------------------------------------------
131
132     /**
133      * Factory Method to allow alternate methods of creating and configuring
134      * XMLReader objects
135      *
136      * @return DOCUMENT ME!
137      *
138      * @throws SAXException
139      * DOCUMENT ME!
140      */
141     protected XMLReader JavaDoc createXMLReader() throws SAXException JavaDoc {
142         return SAXHelper.createXMLReader(true);
143     }
144
145     /**
146      * Configures the XMLReader before use
147      *
148      * @throws SAXException
149      * DOCUMENT ME!
150      */
151     protected void configureReader() throws SAXException JavaDoc {
152         ContentHandler JavaDoc handler = xmlReader.getContentHandler();
153
154         if (handler == null) {
155             xmlReader.setContentHandler(new DefaultHandler JavaDoc());
156         }
157
158         // configure validation support
159 xmlReader.setFeature("http://xml.org/sax/features/validation", true);
160
161         // configure namespace support
162 xmlReader.setFeature("http://xml.org/sax/features/namespaces", true);
163         xmlReader.setFeature("http://xml.org/sax/features/namespace-prefixes",
164                 false);
165     }
166 }
167
168 /*
169  * Redistribution and use of this software and associated documentation
170  * ("Software"), with or without modification, are permitted provided that the
171  * following conditions are met:
172  *
173  * 1. Redistributions of source code must retain copyright statements and
174  * notices. Redistributions must also contain a copy of this document.
175  *
176  * 2. Redistributions in binary form must reproduce the above copyright notice,
177  * this list of conditions and the following disclaimer in the documentation
178  * and/or other materials provided with the distribution.
179  *
180  * 3. The name "DOM4J" must not be used to endorse or promote products derived
181  * from this Software without prior written permission of MetaStuff, Ltd. For
182  * written permission, please contact dom4j-info@metastuff.com.
183  *
184  * 4. Products derived from this Software may not be called "DOM4J" nor may
185  * "DOM4J" appear in their names without prior written permission of MetaStuff,
186  * Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
187  *
188  * 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
189  *
190  * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND
191  * ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
192  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
193  * ARE DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE
194  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
195  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
196  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
197  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
198  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
199  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
200  * POSSIBILITY OF SUCH DAMAGE.
201  *
202  * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
203  */
204
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