001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019
020package org.apache.commons.compress.utils;
021
022import java.nio.charset.Charset;
023import java.nio.charset.StandardCharsets;
024
025/**
026 * Charsets required of every implementation of the Java platform.
027 *
028 * From the Java documentation <a href="https://docs.oracle.com/javase/8/docs/api/java/nio/charset/Charset.html">Standard charsets</a>:
029 * <p>
030 * <cite>Every implementation of the Java platform is required to support the following character encodings. Consult the release documentation for your
031 * implementation to see if any other encodings are supported. Consult the release documentation for your implementation to see if any other encodings are
032 * supported. </cite>
033 * </p>
034 *
035 * <dl>
036 * <dt>{@code US-ASCII}</dt>
037 * <dd>Seven-bit ASCII, a.k.a. ISO646-US, a.k.a. the Basic Latin block of the Unicode character set.</dd>
038 * <dt>{@code ISO-8859-1}</dt>
039 * <dd>ISO Latin Alphabet No. 1, a.k.a. ISO-LATIN-1.</dd>
040 * <dt>{@code UTF-8}</dt>
041 * <dd>Eight-bit Unicode Transformation Format.</dd>
042 * <dt>{@code UTF-16BE}</dt>
043 * <dd>Sixteen-bit Unicode Transformation Format, big-endian byte order.</dd>
044 * <dt>{@code UTF-16LE}</dt>
045 * <dd>Sixteen-bit Unicode Transformation Format, little-endian byte order.</dd>
046 * <dt>{@code UTF-16}</dt>
047 * <dd>Sixteen-bit Unicode Transformation Format, byte order specified by a mandatory initial byte-order mark (either order accepted on input, big-endian used
048 * on output.)</dd>
049 * </dl>
050 *
051 * @see <a href="https://docs.oracle.com/javase/8/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
052 * @see StandardCharsets
053 * @since 1.4
054 * @deprecated Use {@link org.apache.commons.io.Charsets}.
055 */
056@Deprecated
057public class Charsets {
058
059    //
060    // This class should only contain Charset instances for required encodings. This guarantees that it will load correctly and
061    // without delay on all Java platforms.
062    //
063
064    /**
065     * ISO Latin Alphabet No. 1, a.k.a. ISO-LATIN-1.
066     * <p>
067     * Every implementation of the Java platform is required to support this character encoding.
068     * </p>
069     *
070     * @see <a href="https://docs.oracle.com/javase/8/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
071     * @deprecated replaced by {@link StandardCharsets} in Java 7
072     */
073    @Deprecated
074    public static final Charset ISO_8859_1 = StandardCharsets.ISO_8859_1;
075
076    /**
077     * <p>
078     * Seven-bit ASCII, also known as ISO646-US, also known as the Basic Latin block of the Unicode character set.
079     * </p>
080     * <p>
081     * Every implementation of the Java platform is required to support this character encoding.
082     * </p>
083     *
084     * @see <a href="https://docs.oracle.com/javase/8/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
085     * @deprecated replaced by {@link StandardCharsets} in Java 7
086     */
087    @Deprecated
088    public static final Charset US_ASCII = StandardCharsets.US_ASCII;
089
090    /**
091     * <p>
092     * Sixteen-bit Unicode Transformation Format, The byte order specified by a mandatory initial byte-order mark (either order accepted on input, big-endian
093     * used on output)
094     * </p>
095     * <p>
096     * Every implementation of the Java platform is required to support this character encoding.
097     * </p>
098     *
099     * @see <a href="https://docs.oracle.com/javase/8/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
100     * @deprecated replaced by {@link StandardCharsets} in Java 7
101     */
102    @Deprecated
103    public static final Charset UTF_16 = StandardCharsets.UTF_16;
104
105    /**
106     * <p>
107     * Sixteen-bit Unicode Transformation Format, big-endian byte order.
108     * </p>
109     * <p>
110     * Every implementation of the Java platform is required to support this character encoding.
111     * </p>
112     *
113     * @see <a href="https://docs.oracle.com/javase/8/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
114     * @deprecated replaced by {@link StandardCharsets} in Java 7
115     */
116    @Deprecated
117    public static final Charset UTF_16BE = StandardCharsets.UTF_16BE;
118
119    /**
120     * <p>
121     * Sixteen-bit Unicode Transformation Format, little-endian byte order.
122     * </p>
123     * <p>
124     * Every implementation of the Java platform is required to support this character encoding.
125     * </p>
126     *
127     * @see <a href="https://docs.oracle.com/javase/8/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
128     * @deprecated replaced by {@link StandardCharsets} in Java 7
129     */
130    @Deprecated
131    public static final Charset UTF_16LE = StandardCharsets.UTF_16LE;
132
133    /**
134     * <p>
135     * Eight-bit Unicode Transformation Format.
136     * </p>
137     * <p>
138     * Every implementation of the Java platform is required to support this character encoding.
139     * </p>
140     *
141     * @see <a href="https://docs.oracle.com/javase/8/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
142     * @deprecated replaced by {@link StandardCharsets} in Java 7
143     */
144    @Deprecated
145    public static final Charset UTF_8 = StandardCharsets.UTF_8;
146
147    /**
148     * Returns the given Charset or the default Charset if the given Charset is null.
149     *
150     * @param charset A charset or null.
151     * @return the given Charset or the default Charset if the given Charset is null
152     */
153    public static Charset toCharset(final Charset charset) {
154        return charset == null ? Charset.defaultCharset() : charset;
155    }
156
157    /**
158     * Returns a Charset for the named charset. If the name is null, return the default Charset.
159     *
160     * @param charset The name of the requested charset, may be null.
161     * @return a Charset for the named charset
162     * @throws java.nio.charset.UnsupportedCharsetException If the named charset is unavailable
163     * @throws java.nio.charset.IllegalCharsetNameException If the given charset name is illegal
164     */
165    public static Charset toCharset(final String charset) {
166        return charset == null ? Charset.defaultCharset() : Charset.forName(charset);
167    }
168
169    /**
170     * Constructs a new instance.
171     */
172    public Charsets() {
173        // empty
174    }
175}