1 /*
2 * Copyright (c) 2014, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package sun.net.www.protocol.jrt;
27
28 import java.io.ByteArrayInputStream;
29 import java.io.IOException;
30 import java.io.InputStream;
31 import java.net.MalformedURLException;
32 import java.net.URL;
33 import java.security.AccessController;
34 import java.security.Permission;
35 import java.security.PrivilegedAction;
36
37 import jdk.internal.jimage.ImageLocation;
38 import jdk.internal.jimage.ImageReader;
39 import jdk.internal.jimage.ImageReaderFactory;
40
41 import jdk.internal.loader.URLClassPath;
42 import jdk.internal.loader.Resource;
43 import sun.net.www.ParseUtil;
44 import sun.net.www.URLConnection;
45
46 /**
47 * URLConnection implementation that can be used to connect to resources
48 * contained in the runtime image.
49 */
50 public class JavaRuntimeURLConnection extends URLConnection {
51
52 // ImageReader to access resources in jimage
53 private static final ImageReader reader;
54 static {
55 PrivilegedAction<ImageReader> pa = ImageReaderFactory::getImageReader;
56 reader = AccessController.doPrivileged(pa);
57 }
58
59 // the module and resource name in the URL
60 private final String module;
61 private final String name;
62
63 // the Resource when connected
64 private volatile Resource resource;
65
66 JavaRuntimeURLConnection(URL url) throws IOException {
67 super(url);
68 String path = url.getPath();
69 if (path.isEmpty() || path.charAt(0) != '/')
70 throw new MalformedURLException(url + " missing path or /");
71 if (path.length() == 1) {
72 this.module = null;
73 this.name = null;
74 } else {
75 int pos = path.indexOf('/', 1);
76 if (pos == -1) {
77 this.module = path.substring(1);
78 this.name = null;
79 } else {
80 this.module = path.substring(1, pos);
81 this.name = ParseUtil.decode(path.substring(pos+1));
82 }
83 }
84 }
85
86 /**
87 * Finds a resource in a module, returning {@code null} if the resource
88 * is not found.
89 */
90 private static Resource findResource(String module, String name) {
91 if (reader != null) {
92 URL url = toJrtURL(module, name);
93 ImageLocation location = reader.findLocation(module, name);
94 if (location != null && URLClassPath.checkURL(url) != null) {
95 return new Resource() {
96 @Override
97 public String getName() {
98 return name;
99 }
100 @Override
101 public URL getURL() {
102 return url;
103 }
104 @Override
105 public URL getCodeSourceURL() {
106 return toJrtURL(module);
107 }
108 @Override
109 public InputStream getInputStream() throws IOException {
110 byte[] resource = reader.getResource(location);
111 return new ByteArrayInputStream(resource);
112 }
113 @Override
114 public int getContentLength() {
115 long size = location.getUncompressedSize();
116 return (size > Integer.MAX_VALUE) ? -1 : (int) size;
117 }
118 };
119 }
120 }
121 return null;
122 }
123
124 @Override
125 public synchronized void connect() throws IOException {
126 if (!connected) {
127 if (name == null) {
128 String s = (module == null) ? "" : module;
129 throw new IOException("cannot connect to jrt:/" + s);
130 }
131 resource = findResource(module, name);
132 if (resource == null)
133 throw new IOException(module + "/" + name + " not found");
134 connected = true;
135 }
136 }
137
138 @Override
139 public InputStream getInputStream() throws IOException {
140 connect();
141 return resource.getInputStream();
142 }
143
144 @Override
145 public long getContentLengthLong() {
146 try {
147 connect();
148 return resource.getContentLength();
149 } catch (IOException ioe) {
150 return -1L;
151 }
152 }
153
154 @Override
155 public int getContentLength() {
156 long len = getContentLengthLong();
157 return len > Integer.MAX_VALUE ? -1 : (int)len;
158 }
159
160 @Override
161 public Permission getPermission() {
162 return new RuntimePermission("accessSystemModules");
163 }
164
165 /**
166 * Returns a jrt URL for the given module and resource name.
167 */
168 private static URL toJrtURL(String module, String name) {
169 try {
170 return new URL("jrt:/" + module + "/" + name);
171 } catch (MalformedURLException e) {
172 throw new InternalError(e);
173 }
174 }
175
176 /**
177 * Returns a jrt URL for the given module.
178 */
179 private static URL toJrtURL(String module) {
180 try {
181 return new URL("jrt:/" + module);
182 } catch (MalformedURLException e) {
183 throw new InternalError(e);
184 }
185 }
186 }