/*

 * Copyright (c) 1996, 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

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/*

 * (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved

 * (C) Copyright IBM Corp. 1996 - 1998 - All Rights Reserved

 *

 * The original version of this source code and documentation

 * is copyrighted and owned by Taligent, Inc., a wholly-owned

 * subsidiary of IBM. These materials are provided under terms

 * of a License Agreement between Taligent and Sun. This technology

 * is protected by multiple US and International patents.

 *

 * This notice and attribution to Taligent may not be removed.

 * Taligent is a registered trademark of Taligent, Inc.

 */

package java.util;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.Reader;

import java.io.IOException;

import java.nio.charset.MalformedInputException;

import java.nio.charset.StandardCharsets;

import java.nio.charset.UnmappableCharacterException;

import sun.security.action.GetPropertyAction;

import sun.util.PropertyResourceBundleCharset;

import sun.util.ResourceBundleEnumeration;

/**

 * <code>PropertyResourceBundle</code> is a concrete subclass of

 * <code>ResourceBundle</code> that manages resources for a locale

 * using a set of static strings from a property file. See

 * {@link ResourceBundle ResourceBundle} for more information about resource

 * bundles.

 *

 * <p>

 * Unlike other types of resource bundle, you don't subclass

 * <code>PropertyResourceBundle</code>.  Instead, you supply properties

 * files containing the resource data.  <code>ResourceBundle.getBundle</code>

 * will automatically look for the appropriate properties file and create a

 * <code>PropertyResourceBundle</code> that refers to it. See

 * {@link ResourceBundle#getBundle(String, Locale, ClassLoader) ResourceBundle.getBundle}

 * for a complete description of the search and instantiation strategy.

 *

 * <p>

 * The following <a id="sample">example</a> shows a member of a resource

 * bundle family with the base name "MyResources".

 * The text defines the bundle "MyResources_de",

 * the German member of the bundle family.

 * This member is based on <code>PropertyResourceBundle</code>, and the text

 * therefore is the content of the file "MyResources_de.properties"

 * (a related <a href="ListResourceBundle.html#sample">example</a> shows

 * how you can add bundles to this family that are implemented as subclasses

 * of <code>ListResourceBundle</code>).

 * The keys in this example are of the form "s1" etc. The actual

 * keys are entirely up to your choice, so long as they are the same as

 * the keys you use in your program to retrieve the objects from the bundle.

 * Keys are case-sensitive.

 * <blockquote>

 * <pre>

 * # MessageFormat pattern

 * s1=Die Platte \"{1}\" enthält {0}.

 *

 * # location of {0} in pattern

 * s2=1

 *

 * # sample disk name

 * s3=Meine Platte

 *

 * # first ChoiceFormat choice

 * s4=keine Dateien

 *

 * # second ChoiceFormat choice

 * s5=eine Datei

 *

 * # third ChoiceFormat choice

 * s6={0,number} Dateien

 *

 * # sample date

 * s7=3. März 1996

 * </pre>

 * </blockquote>

 *

 * @apiNote

 * {@code PropertyResourceBundle} can be constructed either

 * from an {@code InputStream} or a {@code Reader}, which represents a property file.

 * Constructing a {@code PropertyResourceBundle} instance from an {@code InputStream}

 * requires that the input stream be encoded in {@code UTF-8}. By default, if a

 * {@link java.nio.charset.MalformedInputException} or an

 * {@link java.nio.charset.UnmappableCharacterException} occurs on reading the

 * input stream, then the {@code PropertyResourceBundle} instance resets to the state

 * before the exception, re-reads the input stream in {@code ISO-8859-1}, and

 * continues reading. If the system property

 * {@code java.util.PropertyResourceBundle.encoding} is set to either

 * "ISO-8859-1" or "UTF-8", the input stream is solely read in that encoding,

 * and throws the exception if it encounters an invalid sequence.

 * If "ISO-8859-1" is specified, characters that cannot be represented in

 * ISO-8859-1 encoding must be represented by Unicode Escapes as defined in section

 * 3.3 of <cite>The Java&trade; Language Specification</cite>

 * whereas the other constructor which takes a {@code Reader} does not have that limitation.

 * Other encoding values are ignored for this system property.

 * The system property is read and evaluated when initializing this class.

 * Changing or removing the property has no effect after the initialization.

 *

 * @implSpec

 * The implementation of a {@code PropertyResourceBundle} subclass must be

 * thread-safe if it's simultaneously used by multiple threads. The default

 * implementations of the non-abstract methods in this class are thread-safe.

 *

 * @see ResourceBundle

 * @see ListResourceBundle

 * @see Properties

 * @since 1.1

 */

public class PropertyResourceBundle extends ResourceBundle {

    // Check whether the strict encoding is specified.

    // The possible encoding is either "ISO-8859-1" or "UTF-8".

    private static final String encoding = GetPropertyAction

        .privilegedGetProperty("java.util.PropertyResourceBundle.encoding", "")

        .toUpperCase(Locale.ROOT);

    /**

     * Creates a property resource bundle from an {@link java.io.InputStream

     * InputStream}. This constructor reads the property file in UTF-8 by default.

     * If a {@link java.nio.charset.MalformedInputException} or an

     * {@link java.nio.charset.UnmappableCharacterException} occurs on reading the

     * input stream, then the PropertyResourceBundle instance resets to the state

     * before the exception, re-reads the input stream in {@code ISO-8859-1} and

     * continues reading. If the system property

     * {@code java.util.PropertyResourceBundle.encoding} is set to either

     * "ISO-8859-1" or "UTF-8", the input stream is solely read in that encoding,

     * and throws the exception if it encounters an invalid sequence. Other

     * encoding values are ignored for this system property.

     * The system property is read and evaluated when initializing this class.

     * Changing or removing the property has no effect after the initialization.

     *

     * @param stream an InputStream that represents a property file

     *        to read from.

     * @throws IOException if an I/O error occurs

     * @throws NullPointerException if <code>stream</code> is null

     * @throws IllegalArgumentException if {@code stream} contains a

     *     malformed Unicode escape sequence.

     * @throws MalformedInputException if the system property

     *     {@code java.util.PropertyResourceBundle.encoding} is set to "UTF-8"

     *     and {@code stream} contains an invalid UTF-8 byte sequence.

     * @throws UnmappableCharacterException if the system property

     *     {@code java.util.PropertyResourceBundle.encoding} is set to "UTF-8"

     *     and {@code stream} contains an unmappable UTF-8 byte sequence.

     */

    @SuppressWarnings({"unchecked", "rawtypes"})

    public PropertyResourceBundle (InputStream stream) throws IOException {

        this(new InputStreamReader(stream,

            "ISO-8859-1".equals(encoding) ?

                StandardCharsets.ISO_8859_1.newDecoder() :

                new PropertyResourceBundleCharset("UTF-8".equals(encoding)).newDecoder()));

    }

    /**

     * Creates a property resource bundle from a {@link java.io.Reader

     * Reader}.  Unlike the constructor

     * {@link #PropertyResourceBundle(java.io.InputStream) PropertyResourceBundle(InputStream)},

     * there is no limitation as to the encoding of the input property file.

     *

     * @param reader a Reader that represents a property file to

     *        read from.

     * @throws IOException if an I/O error occurs

     * @throws NullPointerException if <code>reader</code> is null

     * @throws IllegalArgumentException if a malformed Unicode escape sequence appears

     *     from {@code reader}.

     * @since 1.6

     */

    @SuppressWarnings({"unchecked", "rawtypes"})

    public PropertyResourceBundle (Reader reader) throws IOException {

        Properties properties = new Properties();

        properties.load(reader);

        lookup = new HashMap(properties);

    }

    // Implements java.util.ResourceBundle.handleGetObject; inherits javadoc specification.

    public Object handleGetObject(String key) {

        if (key == null) {

            throw new NullPointerException();

        }

        return lookup.get(key);

    }

    /**

     * Returns an <code>Enumeration</code> of the keys contained in

     * this <code>ResourceBundle</code> and its parent bundles.

     *

     * @return an <code>Enumeration</code> of the keys contained in

     *         this <code>ResourceBundle</code> and its parent bundles.

     * @see #keySet()

     */

    public Enumeration<String> getKeys() {

        ResourceBundle parent = this.parent;

        return new ResourceBundleEnumeration(lookup.keySet(),

                (parent != null) ? parent.getKeys() : null);

    }

    /**

     * Returns a <code>Set</code> of the keys contained

     * <em>only</em> in this <code>ResourceBundle</code>.

     *

     * @return a <code>Set</code> of the keys contained only in this

     *         <code>ResourceBundle</code>

     * @since 1.6

     * @see #keySet()

     */

    protected Set<String> handleKeySet() {

        return lookup.keySet();

    }

    // ==================privates====================

    private final Map<String,Object> lookup;

}