1 /*
2 * Copyright (c) 1996, 2006, 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 /*
27 * (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved
28 * (C) Copyright IBM Corp. 1996 - 1998 - All Rights Reserved
29 *
30 * The original version of this source code and documentation
31 * is copyrighted and owned by Taligent, Inc., a wholly-owned
32 * subsidiary of IBM. These materials are provided under terms
33 * of a License Agreement between Taligent and Sun. This technology
34 * is protected by multiple US and International patents.
35 *
36 * This notice and attribution to Taligent may not be removed.
37 * Taligent is a registered trademark of Taligent, Inc.
38 */
39
40 package java.util;
41
42 import java.io.InputStream;
43 import java.io.Reader;
44 import java.io.IOException;
45 import sun.util.ResourceBundleEnumeration;
46
47 /**
48 * <code>PropertyResourceBundle</code> is a concrete subclass of
49 * <code>ResourceBundle</code> that manages resources for a locale
50 * using a set of static strings from a property file. See
51 * {@link ResourceBundle ResourceBundle} for more information about resource
52 * bundles.
53 *
54 * <p>
55 * Unlike other types of resource bundle, you don't subclass
56 * <code>PropertyResourceBundle</code>. Instead, you supply properties
57 * files containing the resource data. <code>ResourceBundle.getBundle</code>
58 * will automatically look for the appropriate properties file and create a
59 * <code>PropertyResourceBundle</code> that refers to it. See
60 * {@link ResourceBundle#getBundle(java.lang.String, java.util.Locale, java.lang.ClassLoader) ResourceBundle.getBundle}
61 * for a complete description of the search and instantiation strategy.
62 *
63 * <p>
64 * The following <a name="sample">example</a> shows a member of a resource
65 * bundle family with the base name "MyResources".
66 * The text defines the bundle "MyResources_de",
67 * the German member of the bundle family.
68 * This member is based on <code>PropertyResourceBundle</code>, and the text
69 * therefore is the content of the file "MyResources_de.properties"
70 * (a related <a href="ListResourceBundle.html#sample">example</a> shows
71 * how you can add bundles to this family that are implemented as subclasses
72 * of <code>ListResourceBundle</code>).
73 * The keys in this example are of the form "s1" etc. The actual
74 * keys are entirely up to your choice, so long as they are the same as
75 * the keys you use in your program to retrieve the objects from the bundle.
76 * Keys are case-sensitive.
77 * <blockquote>
78 * <pre>
79 * # MessageFormat pattern
80 * s1=Die Platte \"{1}\" enthält {0}.
81 *
82 * # location of {0} in pattern
83 * s2=1
84 *
85 * # sample disk name
86 * s3=Meine Platte
87 *
88 * # first ChoiceFormat choice
89 * s4=keine Dateien
90 *
91 * # second ChoiceFormat choice
92 * s5=eine Datei
93 *
94 * # third ChoiceFormat choice
95 * s6={0,number} Dateien
96 *
97 * # sample date
98 * s7=3. März 1996
99 * </pre>
100 * </blockquote>
101 *
102 * <p>
103 * <strong>Note:</strong> PropertyResourceBundle can be constructed either
104 * from an InputStream or a Reader, which represents a property file.
105 * Constructing a PropertyResourceBundle instance from an InputStream requires
106 * that the input stream be encoded in ISO-8859-1. In that case, characters
107 * that cannot be represented in ISO-8859-1 encoding must be represented by Unicode Escapes
108 * as defined in section 3.3 of
109 * <cite>The Java™ Language Specification</cite>
110 * whereas the other constructor which takes a Reader does not have that limitation.
111 *
112 * @see ResourceBundle
113 * @see ListResourceBundle
114 * @see Properties
115 * @since JDK1.1
116 */
117 public class PropertyResourceBundle extends ResourceBundle {
118 /**
119 * Creates a property resource bundle from an {@link java.io.InputStream
120 * InputStream}. The property file read with this constructor
121 * must be encoded in ISO-8859-1.
122 *
123 * @param stream an InputStream that represents a property file
124 * to read from.
125 * @throws IOException if an I/O error occurs
126 * @throws NullPointerException if <code>stream</code> is null
127 */
128 public PropertyResourceBundle (InputStream stream) throws IOException {
129 Properties properties = new Properties();
130 properties.load(stream);
131 lookup = new HashMap(properties);
132 }
133
134 /**
135 * Creates a property resource bundle from a {@link java.io.Reader
136 * Reader}. Unlike the constructor
137 * {@link #PropertyResourceBundle(java.io.InputStream) PropertyResourceBundle(InputStream)},
138 * there is no limitation as to the encoding of the input property file.
139 *
140 * @param reader a Reader that represents a property file to
141 * read from.
142 * @throws IOException if an I/O error occurs
143 * @throws NullPointerException if <code>reader</code> is null
144 * @since 1.6
145 */
146 public PropertyResourceBundle (Reader reader) throws IOException {
147 Properties properties = new Properties();
148 properties.load(reader);
149 lookup = new HashMap(properties);
150 }
151
152 // Implements java.util.ResourceBundle.handleGetObject; inherits javadoc specification.
153 public Object handleGetObject(String key) {
154 if (key == null) {
155 throw new NullPointerException();
156 }
157 return lookup.get(key);
158 }
159
160 /**
161 * Returns an <code>Enumeration</code> of the keys contained in
162 * this <code>ResourceBundle</code> and its parent bundles.
163 *
164 * @return an <code>Enumeration</code> of the keys contained in
165 * this <code>ResourceBundle</code> and its parent bundles.
166 * @see #keySet()
167 */
168 public Enumeration<String> getKeys() {
169 ResourceBundle parent = this.parent;
170 return new ResourceBundleEnumeration(lookup.keySet(),
171 (parent != null) ? parent.getKeys() : null);
172 }
173
174 /**
175 * Returns a <code>Set</code> of the keys contained
176 * <em>only</em> in this <code>ResourceBundle</code>.
177 *
178 * @return a <code>Set</code> of the keys contained only in this
179 * <code>ResourceBundle</code>
180 * @since 1.6
181 * @see #keySet()
182 */
183 protected Set<String> handleKeySet() {
184 return lookup.keySet();
185 }
186
187 // ==================privates====================
188
189 private Map<String,Object> lookup;
190 }