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.lang3;
019
020import java.nio.charset.Charset;
021import java.nio.charset.IllegalCharsetNameException;
022
023/**
024 * <p>Character encoding names required of every implementation of the Java platform.</p>
025 *
026 * <p>According to <a href="http://docs.oracle.com/javase/1.3/docs/api/java/lang/package-summary.html#charenc">JRE character
027 * encoding names</a>:</p>
028 *
029 * <p><cite>Every implementation of the Java platform is required to support the following character encodings.
030 * Consult the release documentation for your implementation to see if any other encodings are supported.
031 * </cite></p>
032 *
033 * @see <a href="http://download.oracle.com/javase/1.3/docs/guide/intl/encoding.doc.html">JRE character encoding names</a>
034 * @since 2.1
035 * @version $Id: CharEncoding.java 1459653 2013-03-22 07:37:03Z bayard $
036 */
037public class CharEncoding {
038
039    /**
040     * <p>ISO Latin Alphabet #1, also known as ISO-LATIN-1.</p>
041     *
042     * <p>Every implementation of the Java platform is required to support this character encoding.</p>
043     */
044    public static final String ISO_8859_1 = "ISO-8859-1";
045
046    /**
047     * <p>Seven-bit ASCII, also known as ISO646-US, also known as the Basic Latin block
048     * of the Unicode character set.</p>
049     *
050     * <p>Every implementation of the Java platform is required to support this character encoding.</p>
051     */
052    public static final String US_ASCII = "US-ASCII";
053
054    /**
055     * <p>Sixteen-bit Unicode Transformation Format, byte order specified by a mandatory initial
056     * byte-order mark (either order accepted on input, big-endian used on output).</p>
057     *
058     * <p>Every implementation of the Java platform is required to support this character encoding.</p>
059     */
060    public static final String UTF_16 = "UTF-16";
061
062    /**
063     * <p>Sixteen-bit Unicode Transformation Format, big-endian byte order.</p>
064     *
065     * <p>Every implementation of the Java platform is required to support this character encoding.</p>
066     */
067    public static final String UTF_16BE = "UTF-16BE";
068
069    /**
070     * <p>Sixteen-bit Unicode Transformation Format, little-endian byte order.</p>
071     *
072     * <p>Every implementation of the Java platform is required to support this character encoding.</p>
073     */
074    public static final String UTF_16LE = "UTF-16LE";
075
076    /**
077     * <p>Eight-bit Unicode Transformation Format.</p>
078     *
079     * <p>Every implementation of the Java platform is required to support this character encoding.</p>
080     */
081    public static final String UTF_8 = "UTF-8";
082
083    //-----------------------------------------------------------------------
084    /**
085     * <p>Returns whether the named charset is supported.</p>
086     *
087     * <p>This is similar to <a
088     * href="http://download.oracle.com/javase/1.4.2/docs/api/java/nio/charset/Charset.html#isSupported%28java.lang.String%29">
089     * java.nio.charset.Charset.isSupported(String)</a> but handles more formats</p>
090     *
091     * @param name  the name of the requested charset; may be either a canonical name or an alias, null returns false
092     * @return {@code true} if the charset is available in the current Java virtual machine
093     */
094    public static boolean isSupported(final String name) {
095        if (name == null) {
096            return false;
097        }
098        try {
099            return Charset.isSupported(name);
100        } catch (final IllegalCharsetNameException ex) {
101            return false;
102        }
103    }
104
105}