1 /*
2 * $Header: /u/cvs/Projects/EnhydraOrg/enhydra3x/Enhydra/modules/Tomcat/src/share/org/apache/tomcat/util/Attic/URLResourceReader.java,v 1.2 2000/02/26 02:32:34 shawn Exp $
3 * $Revision: 1.2 $
4 * $Date: 2000/02/26 02:32:34 $
5 *
6 * ====================================================================
7 *
8 * The Apache Software License, Version 1.1
9 *
10 * Copyright (c) 1999 The Apache Software Foundation. All rights
11 * reserved.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 *
17 * 1. Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 *
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in
22 * the documentation and/or other materials provided with the
23 * distribution.
24 *
25 * 3. The end-user documentation included with the redistribution, if
26 * any, must include the following acknowlegement:
27 * "This product includes software developed by the
28 * Apache Software Foundation (http://www.apache.org/)."
29 * Alternately, this acknowlegement may appear in the software itself,
30 * if and wherever such third-party acknowlegements normally appear.
31 *
32 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
33 * Foundation" must not be used to endorse or promote products derived
34 * from this software without prior written permission. For written
35 * permission, please contact apache@apache.org.
36 *
37 * 5. Products derived from this software may not be called "Apache"
38 * nor may "Apache" appear in their names without prior written
39 * permission of the Apache Group.
40 *
41 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
42 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
43 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
44 * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
45 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
46 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
47 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
48 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
49 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
50 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
51 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * SUCH DAMAGE.
53 * ====================================================================
54 *
55 * This software consists of voluntary contributions made by many
56 * individuals on behalf of the Apache Software Foundation. For more
57 * information on the Apache Software Foundation, please see
58 * <http://www.apache.org/>.
59 *
60 * [Additional notices, if required by prior licensing conditions]
61 *
62 */
63
64 package org.apache.tomcat.util;
65
66 import java.util.zip;
67 import java.net;
68 import java.util;
69 import java.io;
70
71 /**
72 * This implementation of URL Resource Reader assumes 2 types
73 * of base urls. A base url that ends with / is considered a
74 * resource folder, whereas a resource that does not end with
75 * / is considered a zip/jar resource folder.
76 *
77 * If the resource folder happens is a zip/jar archive, the
78 * entries are always cached.
79 * For non-zip base urls, one could specify whether or not it should
80 * be cached.
81 *
82 * @author Harish Prabandham
83 */
84 public class URLResourceReader {
85 private Hashtable resourceCache = new Hashtable();
86 private boolean iszip = true;
87 private URL url = null;
88 private boolean cache = true;
89
90 /**
91 * Creates a new URLResourceReader object. You can either give
92 * the URL of the zip/jar file or a base url where to
93 * look for additional resources. If the url ends with
94 * "/" then it is assumed to be a Base URL.
95 * @param The base url to look for the resources.
96 * @param If the base url is not a zip/jar, then true indicates
97 * that entries should be cached, false otherwise.
98 */
99 public URLResourceReader(URL baseurl, boolean cache) throws IOException {
100 this.url = baseurl;
101 this.cache = cache;
102 this.iszip = !url.getFile().endsWith("/");
103 if(this.iszip)
104 this.cache = true;
105 initialize();
106 }
107
108 /**
109 * equivalent to URLResourceReader(baseurl, false)
110 */
111 public URLResourceReader(URL baseurl) throws IOException {
112 this(baseurl, false);
113 }
114
115 /**
116 * Creates a new URLResourceReader object with the given
117 * input stream. The stream is assumed to be a zip/jar
118 * stream.
119 */
120 public URLResourceReader(InputStream is) throws IOException {
121 init(is);
122 }
123
124 private void initialize() throws IOException {
125 if(iszip) {
126 InputStream is = url.openStream();
127 init(is);
128 is.close();
129 }
130 }
131
132 private byte[] readFully(InputStream is) throws IOException {
133 byte[] buf = new byte[1024];
134 int num = 0;
135 ByteArrayOutputStream bout = new ByteArrayOutputStream();
136
137 while( (num = is.read(buf)) != -1) {
138 bout.write(buf, 0, num);
139 }
140
141 return bout.toByteArray();
142 }
143
144 private void init(InputStream is) throws IOException {
145 ZipInputStream zstream = new ZipInputStream(is);
146 ZipEntry entry;
147
148 while( (entry = zstream.getNextEntry()) != null) {
149 byte[] entryData = readFully(zstream);
150 if(cache)
151 resourceCache.put(entry.getName(), entryData);
152 zstream.closeEntry();
153 }
154
155 zstream.close();
156 }
157
158 /**
159 * Returns an Enumeration of all "known" resource names.
160 */
161 public Enumeration getResourceNames() {
162 return resourceCache.keys();
163 }
164
165 /**
166 * Returns an array of bytes read for this resource if the
167 * resource exists. This method blocks until the resource
168 * has been fully read. If the resource does not exist,
169 * this method returns null.
170 */
171 public byte[] getResource(String resource) {
172 // lookup the data in the cache...
173 byte[] data = (byte[]) resourceCache.get(resource);
174 if(data != null) {
175 return data;
176 }
177
178 // if the data was to come from a zip file that we
179 // already read fully & cached , then it is probably
180 // not there.
181 if(iszip) {
182 return null;
183 }
184
185 // Now the only choice left is to make a url connection.
186 try {
187 URL realURL = new URL(url.getProtocol(), url.getHost(),
188 url.getFile() + resource);
189 data = readFully(realURL.openStream());
190 // add it to cache if needed...
191 if(cache)
192 resourceCache.put(resource, data);
193 return data;
194 } catch(Exception e) {
195 return null;
196 }
197 }
198
199 public void close() {
200 resourceCache.clear();
201 resourceCache = null;
202 }
203 }
204
205
206
207
208
209
210
211