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)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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 2002 (C) Intalio, Inc. All Rights Reserved.
42 *
43 * $Id$
44 */
45 package org.exolab.castor.net.util;
46
47 import org.exolab.castor.net.URIResolver;
48 import org.exolab.castor.net.URIException;
49 import org.exolab.castor.net.URILocation;
50
51 /**
52 * The default implementation of URIResolver
53 * @author <a href="mailto:kvisco@intalio.com">Keith Visco</a>
54 * @author <a href="mailto:blandin@intalio.com">Arnaud Blandin</a>
55 * @version $Revision$ $Date: 2003-03-03 02:57:21 -0700 (Mon, 03 Mar 2003) $
56 **/
57 public final class URIResolverImpl implements URIResolver {
58
59 private static final String HTTP_PROTOCOL = "http:";
60 private static final String FILE_PROTOCOL = "file:";
61
62 public URIResolverImpl() {
63 super();
64 } //-- URIResolver;
65
66 /**
67 * Resolves the given href and documentBase.
68 * The href can either be an absolute or a relative URI as defined by
69 * IETF RFC 2396:
70 * <ul>
71 * <li><b>Absolute</b> URI: [scheme]:'//'[authority][absolute path]</li>
72 * <li><b>Relative</b> URI: '//'[authority][absolute path] or [relative path]
73 * or [absolute path].</li>
74 * </ul>
75 *
76 * <p><b>Note</b>:
77 * <ol>
78 * <li>When [authority] is not used then '//' must not be used.</li>
79 * <li>An [absolute path] begins by a '/' sign.</li>
80 * </ol>
81 * For instance the following URIs are valid:
82 * <blockquote>
83 * <pre>
84 * file:/c:/Program Files/MyApp/myresource.xml
85 * file://usr/etc/myresource.xml
86 * http://www.castor.org/index.html
87 * ../relative/index.html
88 * </pre>
89 * </blockquote>
90 * However, the following <b>won't</b> be valid:
91 * <blockquote>
92 * <pre>
93 * file://c:/Program Files/MyApp/myresource.xml
94 * </pre>
95 * </blockquote>
96 *
97 * @return the URILocation for the URI
98 **/
99 public URILocation resolve(String href, String documentBase)
100 throws URIException
101 {
102 URILocation uriLocation = null;
103 boolean stripHostSeparator = (java.io.File.separatorChar == '\\');
104 //--true if the path in the href is absolute
105 boolean absolute = false;
106
107 //1--Is there a scheme? If yes the URI is absolute.
108 //NOTE: only HTTP and File protocols are currently supported.
109 if ( href.startsWith(HTTP_PROTOCOL) || href.startsWith(FILE_PROTOCOL) ) {
110 absolute = true;
111 }
112 //2-- handle relative URIs: '//'<authority>[absolute path]
113 //or [relative path] or [absolute path]
114 if (!absolute) {
115 if (stripHostSeparator) {
116 if (href.startsWith("//"))
117 absolute = true;
118 } else if (href.startsWith("///")) {
119 absolute = true;
120 }
121
122 }
123
124 //3--[relative path]
125 if (!absolute) {
126
127 if (href.startsWith("./"))
128 href = href.substring(2);
129
130 //--resolve using the document base
131 if (documentBase != null) {
132
133 //--resolve the previous directory
134 while (href.startsWith("../")) {
135 href = href.substring(3);
136 documentBase = documentBase.substring(0,documentBase.lastIndexOf('/'));
137 documentBase = documentBase.substring(0,documentBase.lastIndexOf('/')+1);
138 }
139 }//--documentBase != null
140 }
141
142 try {
143 uriLocation = new URILocationImpl(href, documentBase);
144 }
145 catch (RuntimeException ex) {
146 throw new URIException(ex.getMessage(), ex);
147 }
148 return uriLocation;
149 } //-- resolve
150
151 /**
152 * Resolves the given urn. An implementation of this
153 * method may return null if the URN could not be resolved.
154 *
155 * @return the URILocation for the URN
156 */
157 public URILocation resolveURN(String urn)
158 throws URIException
159 {
160 return null;
161 } //-- resolveURN
162
163 } //-- URIResolver