1 /*
2 * Copyright (c) 2005, 2012, 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 sun.util.resources;
42
43 import java.util.Enumeration;
44 import java.util.HashMap;
45 import java.util.HashSet;
46 import java.util.Map;
47 import java.util.ResourceBundle;
48 import java.util.Set;
49 import sun.util.ResourceBundleEnumeration;
50
51 /**
52 * Subclass of <code>ResourceBundle</code> which mimics
53 * <code>ListResourceBundle</code>, but provides more hooks
54 * for specialized subclass behavior. For general description,
55 * see {@link java.util.ListResourceBundle}.
56 * <p>
57 * This class leaves handleGetObject non-final, and
58 * adds a method createMap which allows subclasses to
59 * use specialized Map implementations.
60 */
61 public abstract class OpenListResourceBundle extends ResourceBundle {
62 /**
63 * Sole constructor. (For invocation by subclass constructors, typically
64 * implicit.)
65 */
66 protected OpenListResourceBundle() {
67 }
68
69 // Implements java.util.ResourceBundle.handleGetObject; inherits javadoc specification.
70 public Object handleGetObject(String key) {
71 if (key == null) {
72 throw new NullPointerException();
73 }
74
75 loadLookupTablesIfNecessary();
76 return lookup.get(key); // this class ignores locales
77 }
78
79 /**
80 * Implementation of ResourceBundle.getKeys.
81 */
82 public Enumeration<String> getKeys() {
83 ResourceBundle parent = this.parent;
84 return new ResourceBundleEnumeration(handleGetKeys(),
85 (parent != null) ? parent.getKeys() : null);
86 }
87
88 /**
89 * Returns a set of keys provided in this resource bundle
90 */
91 public Set<String> handleGetKeys() {
92 loadLookupTablesIfNecessary();
93
94 return lookup.keySet();
95 }
96
97 @Override
98 public Set<String> keySet() {
99 if (keyset != null) {
100 return keyset;
101 }
102 Set<String> ks = new HashSet<>();
103 ks.addAll(handleGetKeys());
104 if (parent != null) {
105 ks.addAll(parent.keySet());
106 }
107 synchronized (this) {
108 if (keyset == null) {
109 keyset = ks;
110 }
111 }
112 return keyset;
113 }
114
115 /**
116 * Returns the parent bundle
117 */
118 public OpenListResourceBundle getParent() {
119 return (OpenListResourceBundle)parent;
120 }
121
122 /**
123 * See ListResourceBundle class description.
124 */
125 abstract protected Object[][] getContents();
126
127 /**
128 * Load lookup tables if they haven't been loaded already.
129 */
130 void loadLookupTablesIfNecessary() {
131 if (lookup == null) {
132 loadLookup();
133 }
134 }
135
136 /**
137 * We lazily load the lookup hashtable. This function does the
138 * loading.
139 */
140 private void loadLookup() {
141 Object[][] contents = getContents();
142 Map<String, Object> temp = createMap(contents.length);
143 for (int i = 0; i < contents.length; ++i) {
144 // key must be non-null String, value must be non-null
145 String key = (String) contents[i][0];
146 Object value = contents[i][1];
147 if (key == null || value == null) {
148 throw new NullPointerException();
149 }
150 temp.put(key, value);
151 }
152 synchronized (this) {
153 if (lookup == null) {
154 lookup = temp;
155 }
156 }
157 }
158
159 /**
160 * Lets subclasses provide specialized Map implementations.
161 * Default uses HashMap.
162 */
163 protected Map<String, Object> createMap(int size) {
164 return new HashMap<>(size);
165 }
166
167 private volatile Map<String, Object> lookup = null;
168 private volatile Set<String> keyset;
169 }