1 /*
2 * Copyright (c) 1999, 2011, 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 com.sun.naming.internal;
27
28 import java.io.InputStream;
29 import java.io.IOException;
30 import java.net.MalformedURLException;
31 import java.net.URL;
32 import java.util.StringTokenizer;
33 import java.util.Vector;
34
35 import javax.naming.NamingEnumeration;
36
37 /**
38 * VersionHelper was used by JNDI to accommodate differences between
39 * JDK 1.1.x and the Java 2 platform. As this is no longer necessary
40 * since JNDI's inclusion in the platform, this class currently
41 * serves as a set of utilities for performing system-level things,
42 * such as class-loading and reading system properties.
43 *
44 * @author Rosanna Lee
45 * @author Scott Seligman
46 */
47
48 public abstract class VersionHelper {
49 private static VersionHelper helper = null;
50
51 final static String[] PROPS = new String[] {
52 javax.naming.Context.INITIAL_CONTEXT_FACTORY,
53 javax.naming.Context.OBJECT_FACTORIES,
54 javax.naming.Context.URL_PKG_PREFIXES,
55 javax.naming.Context.STATE_FACTORIES,
56 javax.naming.Context.PROVIDER_URL,
57 javax.naming.Context.DNS_URL,
58 // The following shouldn't create a runtime dependence on ldap package.
59 javax.naming.ldap.LdapContext.CONTROL_FACTORIES
60 };
61
62 public final static int INITIAL_CONTEXT_FACTORY = 0;
63 public final static int OBJECT_FACTORIES = 1;
64 public final static int URL_PKG_PREFIXES = 2;
65 public final static int STATE_FACTORIES = 3;
66 public final static int PROVIDER_URL = 4;
67 public final static int DNS_URL = 5;
68 public final static int CONTROL_FACTORIES = 6;
69
70 VersionHelper() {} // Disallow anyone from creating one of these.
71
72 static {
73 helper = new VersionHelper12();
74 }
75
76 public static VersionHelper getVersionHelper() {
77 return helper;
78 }
79
80 public abstract Class<?> loadClass(String className)
81 throws ClassNotFoundException;
82
83 abstract Class<?> loadClass(String className, ClassLoader cl)
84 throws ClassNotFoundException;
85
86 public abstract Class<?> loadClass(String className, String codebase)
87 throws ClassNotFoundException, MalformedURLException;
88
89 /*
90 * Returns a JNDI property from the system properties. Returns
91 * null if the property is not set, or if there is no permission
92 * to read it.
93 */
94 abstract String getJndiProperty(int i);
95
96 /*
97 * Reads each property in PROPS from the system properties, and
98 * returns their values -- in order -- in an array. For each
99 * unset property, the corresponding array element is set to null.
100 * Returns null if there is no permission to call System.getProperties().
101 */
102 abstract String[] getJndiProperties();
103
104 /*
105 * Returns the resource of a given name associated with a particular
106 * class (never null), or null if none can be found.
107 */
108 abstract InputStream getResourceAsStream(Class<?> c, String name);
109
110 /*
111 * Returns an input stream for a file in <java.home>/lib,
112 * or null if it cannot be located or opened.
113 *
114 * @param filename The file name, sans directory.
115 */
116 abstract InputStream getJavaHomeLibStream(String filename);
117
118 /*
119 * Returns an enumeration (never null) of InputStreams of the
120 * resources of a given name associated with a particular class
121 * loader. Null represents the bootstrap class loader in some
122 * Java implementations.
123 */
124 abstract NamingEnumeration<InputStream> getResources(
125 ClassLoader cl, String name)
126 throws IOException;
127
128 /*
129 * Returns the context class loader associated with the current thread.
130 * Null indicates the bootstrap class loader in some Java implementations.
131 *
132 * @throws SecurityException if the class loader is not accessible.
133 */
134 abstract ClassLoader getContextClassLoader();
135
136 static protected URL[] getUrlArray(String codebase)
137 throws MalformedURLException {
138 // Parse codebase into separate URLs
139 StringTokenizer parser = new StringTokenizer(codebase);
140 Vector<String> vec = new Vector<>(10);
141 while (parser.hasMoreTokens()) {
142 vec.addElement(parser.nextToken());
143 }
144 String[] url = new String[vec.size()];
145 for (int i = 0; i < url.length; i++) {
146 url[i] = vec.elementAt(i);
147 }
148
149 URL[] urlArray = new URL[url.length];
150 for (int i = 0; i < urlArray.length; i++) {
151 urlArray[i] = new URL(url[i]);
152 }
153 return urlArray;
154 }
155 }