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1   /*
2    * Copyright (c) 1996, 2013, 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}\" enth&auml;lt {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. M&auml;rz 1996
99   * </pre>
100  * </blockquote>
101  *
102  * <p>
103  * The implementation of a {@code PropertyResourceBundle} subclass must be
104  * thread-safe if it's simultaneously used by multiple threads. The default
105  * implementations of the non-abstract methods in this class are thread-safe.
106  *
107  * <p>
108  * <strong>Note:</strong> PropertyResourceBundle can be constructed either
109  * from an InputStream or a Reader, which represents a property file.
110  * Constructing a PropertyResourceBundle instance from an InputStream requires
111  * that the input stream be encoded in ISO-8859-1.  In that case, characters
112  * that cannot be represented in ISO-8859-1 encoding must be represented by Unicode Escapes
113  * as defined in section 3.3 of
114  * <cite>The Java&trade; Language Specification</cite>
115  * whereas the other constructor which takes a Reader does not have that limitation.
116  *
117  * @see ResourceBundle
118  * @see ListResourceBundle
119  * @see Properties
120  * @since JDK1.1
121  */
122 public class PropertyResourceBundle extends ResourceBundle {
123     /**
124      * Creates a property resource bundle from an {@link java.io.InputStream
125      * InputStream}.  The property file read with this constructor
126      * must be encoded in ISO-8859-1.
127      *
128      * @param stream an InputStream that represents a property file
129      *        to read from.
130      * @throws IOException if an I/O error occurs
131      * @throws NullPointerException if <code>stream</code> is null
132      * @throws IllegalArgumentException if {@code stream} contains a
133      *     malformed Unicode escape sequence.
134      */
135     @SuppressWarnings({"unchecked", "rawtypes"})
136     public PropertyResourceBundle (InputStream stream) throws IOException {
137         Properties properties = new Properties();
138         properties.load(stream);
139         lookup = new HashMap(properties);
140     }
141 
142     /**
143      * Creates a property resource bundle from a {@link java.io.Reader
144      * Reader}.  Unlike the constructor
145      * {@link #PropertyResourceBundle(java.io.InputStream) PropertyResourceBundle(InputStream)},
146      * there is no limitation as to the encoding of the input property file.
147      *
148      * @param reader a Reader that represents a property file to
149      *        read from.
150      * @throws IOException if an I/O error occurs
151      * @throws NullPointerException if <code>reader</code> is null
152      * @throws IllegalArgumentException if a malformed Unicode escape sequence appears
153      *     from {@code reader}.
154      * @since 1.6
155      */
156     @SuppressWarnings({"unchecked", "rawtypes"})
157     public PropertyResourceBundle (Reader reader) throws IOException {
158         Properties properties = new Properties();
159         properties.load(reader);
160         lookup = new HashMap(properties);
161     }
162 
163     // Implements java.util.ResourceBundle.handleGetObject; inherits javadoc specification.
164     public Object handleGetObject(String key) {
165         if (key == null) {
166             throw new NullPointerException();
167         }
168         return lookup.get(key);
169     }
170 
171     /**
172      * Returns an <code>Enumeration</code> of the keys contained in
173      * this <code>ResourceBundle</code> and its parent bundles.
174      *
175      * @return an <code>Enumeration</code> of the keys contained in
176      *         this <code>ResourceBundle</code> and its parent bundles.
177      * @see #keySet()
178      */
179     public Enumeration<String> getKeys() {
180         ResourceBundle parent = this.parent;
181         return new ResourceBundleEnumeration(lookup.keySet(),
182                 (parent != null) ? parent.getKeys() : null);
183     }
184 
185     /**
186      * Returns a <code>Set</code> of the keys contained
187      * <em>only</em> in this <code>ResourceBundle</code>.
188      *
189      * @return a <code>Set</code> of the keys contained only in this
190      *         <code>ResourceBundle</code>
191      * @since 1.6
192      * @see #keySet()
193      */
194     protected Set<String> handleKeySet() {
195         return lookup.keySet();
196     }
197 
198     // ==================privates====================
199 
200     private Map<String,Object> lookup;
201 }