Source code: java/security/Provider.java
1 /* Provider.java -- Security provider information
2 Copyright (C) 1998, 1999, 2000, 2002 Free Software Foundation, Inc.
3
4 This file is part of GNU Classpath.
5
6 GNU Classpath is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
9 any later version.
10
11 GNU Classpath is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GNU Classpath; see the file COPYING. If not, write to the
18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
19 02110-1301 USA.
20
21 Linking this library statically or dynamically with other modules is
22 making a combined work based on this library. Thus, the terms and
23 conditions of the GNU General Public License cover the whole
24 combination.
25
26 As a special exception, the copyright holders of this library give you
27 permission to link this library with independent modules to produce an
28 executable, regardless of the license terms of these independent
29 modules, and to copy and distribute the resulting executable under
30 terms of your choice, provided that you also meet, for each linked
31 independent module, the terms and conditions of the license of that
32 module. An independent module is a module which is not derived from
33 or based on this library. If you modify this library, you may extend
34 this exception to your version of the library, but you are not
35 obligated to do so. If you do not wish to do so, delete this
36 exception statement from your version. */
37
38 package java.security;
39
40 import java.io.Serializable;
41 import java.util.Properties;
42
43 /**
44 * This class represents a Java security architecture service provider.
45 * The services provided by a such a provider can range from security
46 * algorithms to key generation.
47 * <p>
48 * Providers are installed by name and version number. There is one
49 * standard provider supplied with the class library. This is the
50 * "GNU" provider, which can also be accessed by the alias "SUN" for
51 * compatibility with the JDK.
52 *
53 * @version 0.0
54 *
55 * @author Aaron M. Renn (arenn@urbanophile.com)
56 */
57 public abstract class Provider extends Properties implements Serializable
58 {
59 private static final long serialVersionUID = -4298000515446427739L;
60
61 /**
62 * This is a textual description of the provider
63 */
64 private String info;
65
66 /**
67 * This is the name of the provider
68 */
69 private String name;
70
71 /**
72 * This is the version number of the provider
73 */
74 private double version;
75
76 /**
77 * This method initializes a new instance of <code>Provider</code> to have
78 * the specified name, version, and description information.
79 *
80 * @param name The name to assign to this <code>Provider</code>.
81 * @param version The version number for this <code>Provider</code>.
82 * @param info A textual description of this provider.
83 */
84 protected Provider(String name, double version, String info)
85 {
86 this.name = name;
87 this.version = version;
88 this.info = info;
89 }
90
91 /**
92 * This method returns the name assigned to this <code>Provider</code>.
93 *
94 * @return The <code>Provider</code>'s name.
95 */
96 public String getName()
97 {
98 return (name);
99 }
100
101 /**
102 * This method retunrs the version number of this <code>Provider</code>.
103 *
104 * @return The <code>Provider</code>'s version number.
105 */
106 public double getVersion()
107 {
108 return (version);
109 }
110
111 /**
112 * This method returns a textual description of the <code>Provider</code>.
113 *
114 * @return A description of the <code>Provider</code>.
115 */
116 public String getInfo()
117 {
118 return (info);
119 }
120
121 /**
122 * Sets the key property to have the specified value.
123 * <p>
124 * <bold>NOT IMPLEMENTED YET</bold>[
125 * First, if there is a security manager, its <code>checkSecurityAccess</code>
126 * method is called with the string "putProviderProperty."+name, where name is
127 * the provider name, to see if it's ok to set this provider's property
128 * values.
129 * If the default implementation of <code>checkSecurityAccess</code> is used
130 * (that is, that method is not overriden), then this results in a call to the
131 * security manager's <code>checkPermission</code> method with a
132 * <code>SecurityPermission("putProviderProperty."+name)</code>
133 * permission.<br>]
134 *
135 * @param key The property key.
136 * @param value The property value.
137 *
138 * @return The previous value of the specified property (<code>key</code>),
139 * or <code>null</code> if it did not have one.
140 * @throws SecurityException If a security manager exists and its
141 * {@link java.lang.SecurityManager.checkSecurityAccess(java.lang.String)}
142 * method denies access to set property values.
143 * @since Classpath 0.4+cvs, JDK 1.2
144 * @see java.lang.Object.equals(Object)
145 * @see java.util.Hashtable.get(Object)
146 */
147 public Object put(Object key, Object value)
148 {
149 return super.put(toCanonicalKey(key), value);
150 }
151
152 // overrides same in java.util.Hashtable
153 public Object get(Object key)
154 {
155 return super.get(toCanonicalKey(key));
156 }
157
158 /**
159 * This method removes the specified key entry (and its associated value)
160 * from the property mapping list.
161 *
162 * @param key The key to remove
163 *
164 * @return The previous value for this key, or <code>null</code> if no
165 * previous value.
166 */
167 public Object remove(Object key)
168 {
169 return super.remove(toCanonicalKey(key));
170 }
171
172 /**
173 * This method clears the entire property list such that it no longer
174 * contains the properties used to look up the services provided by
175 * the <code>Provider</code>.
176 */
177 public void clear()
178 {
179 super.clear();
180 }
181
182 /**
183 * This method returns a <code>String</code> representation of this
184 * object. This will include the <code>Provider</code> name and
185 * version number.
186 *
187 * @return A <code>String</code> representation of this object.
188 */
189 public String toString()
190 {
191 return (getClass().getName() + ": name=" + getName() + " version=" +
192 version);
193 }
194
195 private Object toCanonicalKey(Object key)
196 {
197 if (key.getClass().isAssignableFrom(String.class)) // is it ours?
198 return ((String) key).toUpperCase(); // use default locale
199 else
200 return key;
201 }
202 }