1 /*
2 * Copyright (c) 1996, 2010, 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
41 package java.util;
42
43 import sun.util.ResourceBundleEnumeration;
44
45 /**
46 * <code>ListResourceBundle</code> is an abstract subclass of
47 * <code>ResourceBundle</code> that manages resources for a locale
48 * in a convenient and easy to use list. See <code>ResourceBundle</code> for
49 * more information about resource bundles in general.
50 *
51 * <P>
52 * Subclasses must override <code>getContents</code> and provide an array,
53 * where each item in the array is a pair of objects.
54 * The first element of each pair is the key, which must be a
55 * <code>String</code>, and the second element is the value associated with
56 * that key.
57 *
58 * <p>
59 * The following <a name="sample">example</a> shows two members of a resource
60 * bundle family with the base name "MyResources".
61 * "MyResources" is the default member of the bundle family, and
62 * "MyResources_fr" is the French member.
63 * These members are based on <code>ListResourceBundle</code>
64 * (a related <a href="PropertyResourceBundle.html#sample">example</a> shows
65 * how you can add a bundle to this family that's based on a properties file).
66 * The keys in this example are of the form "s1" etc. The actual
67 * keys are entirely up to your choice, so long as they are the same as
68 * the keys you use in your program to retrieve the objects from the bundle.
69 * Keys are case-sensitive.
70 * <blockquote>
71 * <pre>
72 *
73 * public class MyResources extends ListResourceBundle {
74 * protected Object[][] getContents() {
75 * return new Object[][] {
76 * // LOCALIZE THIS
77 * {"s1", "The disk \"{1}\" contains {0}."}, // MessageFormat pattern
78 * {"s2", "1"}, // location of {0} in pattern
79 * {"s3", "My Disk"}, // sample disk name
80 * {"s4", "no files"}, // first ChoiceFormat choice
81 * {"s5", "one file"}, // second ChoiceFormat choice
82 * {"s6", "{0,number} files"}, // third ChoiceFormat choice
83 * {"s7", "3 Mar 96"}, // sample date
84 * {"s8", new Dimension(1,5)} // real object, not just string
85 * // END OF MATERIAL TO LOCALIZE
86 * };
87 * }
88 * }
89 *
90 * public class MyResources_fr extends ListResourceBundle {
91 * protected Object[][] getContents() {
92 * return new Object[][] = {
93 * // LOCALIZE THIS
94 * {"s1", "Le disque \"{1}\" {0}."}, // MessageFormat pattern
95 * {"s2", "1"}, // location of {0} in pattern
96 * {"s3", "Mon disque"}, // sample disk name
97 * {"s4", "ne contient pas de fichiers"}, // first ChoiceFormat choice
98 * {"s5", "contient un fichier"}, // second ChoiceFormat choice
99 * {"s6", "contient {0,number} fichiers"}, // third ChoiceFormat choice
100 * {"s7", "3 mars 1996"}, // sample date
101 * {"s8", new Dimension(1,3)} // real object, not just string
102 * // END OF MATERIAL TO LOCALIZE
103 * };
104 * }
105 * }
106 * </pre>
107 * </blockquote>
108 * @see ResourceBundle
109 * @see PropertyResourceBundle
110 * @since JDK1.1
111 */
112 public abstract class ListResourceBundle extends ResourceBundle {
113 /**
114 * Sole constructor. (For invocation by subclass constructors, typically
115 * implicit.)
116 */
117 public ListResourceBundle() {
118 }
119
120 // Implements java.util.ResourceBundle.handleGetObject; inherits javadoc specification.
121 public final Object handleGetObject(String key) {
122 // lazily load the lookup hashtable.
123 if (lookup == null) {
124 loadLookup();
125 }
126 if (key == null) {
127 throw new NullPointerException();
128 }
129 return lookup.get(key); // this class ignores locales
130 }
131
132 /**
133 * Returns an <code>Enumeration</code> of the keys contained in
134 * this <code>ResourceBundle</code> and its parent bundles.
135 *
136 * @return an <code>Enumeration</code> of the keys contained in
137 * this <code>ResourceBundle</code> and its parent bundles.
138 * @see #keySet()
139 */
140 public Enumeration<String> getKeys() {
141 // lazily load the lookup hashtable.
142 if (lookup == null) {
143 loadLookup();
144 }
145
146 ResourceBundle parent = this.parent;
147 return new ResourceBundleEnumeration(lookup.keySet(),
148 (parent != null) ? parent.getKeys() : null);
149 }
150
151 /**
152 * Returns a <code>Set</code> of the keys contained
153 * <em>only</em> in this <code>ResourceBundle</code>.
154 *
155 * @return a <code>Set</code> of the keys contained only in this
156 * <code>ResourceBundle</code>
157 * @since 1.6
158 * @see #keySet()
159 */
160 protected Set<String> handleKeySet() {
161 if (lookup == null) {
162 loadLookup();
163 }
164 return lookup.keySet();
165 }
166
167 /**
168 * Returns an array in which each item is a pair of objects in an
169 * <code>Object</code> array. The first element of each pair is
170 * the key, which must be a <code>String</code>, and the second
171 * element is the value associated with that key. See the class
172 * description for details.
173 *
174 * @return an array of an <code>Object</code> array representing a
175 * key-value pair.
176 */
177 abstract protected Object[][] getContents();
178
179 // ==================privates====================
180
181 /**
182 * We lazily load the lookup hashtable. This function does the
183 * loading.
184 */
185 private synchronized void loadLookup() {
186 if (lookup != null)
187 return;
188
189 Object[][] contents = getContents();
190 HashMap<String,Object> temp = new HashMap<>(contents.length);
191 for (int i = 0; i < contents.length; ++i) {
192 // key must be non-null String, value must be non-null
193 String key = (String) contents[i][0];
194 Object value = contents[i][1];
195 if (key == null || value == null) {
196 throw new NullPointerException();
197 }
198 temp.put(key, value);
199 }
200 lookup = temp;
201 }
202
203 private Map<String,Object> lookup = null;
204 }