001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.codec;
019
020import java.nio.charset.Charset;
021import java.nio.charset.StandardCharsets;
022
023/**
024 * Character encoding names required of every implementation of the Java platform.
025 *
026 * From the Java documentation for {@link Charset}:
027 * <p>
028 * <cite>Every implementation of the Java platform is required to support the following character encodings. Consult the
029 * release documentation for your implementation to see if any other encodings are supported. Consult the release
030 * documentation for your implementation to see if any other encodings are supported.</cite>
031 * </p>
032 *
033 * <ul>
034 * <li>{@code US-ASCII}<p>
035 * Seven-bit ASCII, a.k.a. ISO646-US, a.k.a. the Basic Latin block of the Unicode character set.</p></li>
036 * <li>{@code ISO-8859-1}<p>
037 * ISO Latin Alphabet No. 1, a.k.a. ISO-LATIN-1.</p></li>
038 * <li>{@code UTF-8}<p>
039 * Eight-bit Unicode Transformation Format.</p></li>
040 * <li>{@code UTF-16BE}<p>
041 * Sixteen-bit Unicode Transformation Format, big-endian byte order.</p></li>
042 * <li>{@code UTF-16LE}<p>
043 * Sixteen-bit Unicode Transformation Format, little-endian byte order.</p></li>
044 * <li>{@code UTF-16}<p>
045 * Sixteen-bit Unicode Transformation Format, byte order specified by a mandatory initial byte-order mark (either order
046 * accepted on input, big-endian used on output.)</p></li>
047 * </ul>
048 *
049 * This perhaps would best belong in the [lang] project. Even if a similar interface is defined in [lang], it is not
050 * foreseen that [codec] would be made to depend on [lang].
051 *
052 * <p>
053 * This class is immutable and thread-safe.
054 * </p>
055 *
056 * @see Charset
057 * @since 1.4
058 */
059public class CharEncoding {
060
061    /**
062     * CharEncodingISO Latin Alphabet No. 1, a.k.a. ISO-LATIN-1.
063     * <p>
064     * Every implementation of the Java platform is required to support this character encoding.
065     * </p>
066     *
067     * @see Charset
068     */
069    public static final String ISO_8859_1 = StandardCharsets.ISO_8859_1.name();
070
071    /**
072     * Seven-bit ASCII, also known as ISO646-US, also known as the Basic Latin block of the Unicode character set.
073     * <p>
074     * Every implementation of the Java platform is required to support this character encoding.
075     * </p>
076     *
077     * @see Charset
078     */
079    public static final String US_ASCII = StandardCharsets.US_ASCII.name();
080
081    /**
082     * Sixteen-bit Unicode Transformation Format, The byte order specified by a mandatory initial byte-order mark
083     * (either order accepted on input, big-endian used on output)
084     * <p>
085     * Every implementation of the Java platform is required to support this character encoding.
086     * </p>
087     *
088     * @see Charset
089     */
090    public static final String UTF_16 = StandardCharsets.UTF_16.name();
091
092    /**
093     * Sixteen-bit Unicode Transformation Format, big-endian byte order.
094     * <p>
095     * Every implementation of the Java platform is required to support this character encoding.
096     * </p>
097     *
098     * @see Charset
099     */
100    public static final String UTF_16BE = StandardCharsets.UTF_16BE.name();
101
102    /**
103     * Sixteen-bit Unicode Transformation Format, little-endian byte order.
104     * <p>
105     * Every implementation of the Java platform is required to support this character encoding.
106     * </p>
107     *
108     * @see Charset
109     */
110    public static final String UTF_16LE = StandardCharsets.UTF_16LE.name();
111
112    /**
113     * Eight-bit Unicode Transformation Format.
114     * <p>
115     * Every implementation of the Java platform is required to support this character encoding.
116     * </p>
117     *
118     * @see Charset
119     */
120    public static final String UTF_8 = StandardCharsets.UTF_8.name();
121
122    /**
123     * TODO Make private in 2.0.
124     *
125     * @deprecated TODO Make private in 2.0.
126     */
127    @Deprecated
128    public CharEncoding() {
129        // empty
130    }
131
132}