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 */ 017package org.apache.commons.codec; 018 019import java.nio.charset.Charset; 020 021/** 022 * Charsets required of every implementation of the Java platform. 023 * 024 * From the Java documentation <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard 025 * charsets</a>: 026 * <p> 027 * <cite>Every implementation of the Java platform is required to support the following character encodings. Consult the 028 * release documentation for your implementation to see if any other encodings are supported. Consult the release 029 * documentation for your implementation to see if any other encodings are supported. </cite> 030 * </p> 031 * 032 * <ul> 033 * <li><code>US-ASCII</code><br> 034 * Seven-bit ASCII, a.k.a. ISO646-US, a.k.a. the Basic Latin block of the Unicode character set.</li> 035 * <li><code>ISO-8859-1</code><br> 036 * ISO Latin Alphabet No. 1, a.k.a. ISO-LATIN-1.</li> 037 * <li><code>UTF-8</code><br> 038 * Eight-bit Unicode Transformation Format.</li> 039 * <li><code>UTF-16BE</code><br> 040 * Sixteen-bit Unicode Transformation Format, big-endian byte order.</li> 041 * <li><code>UTF-16LE</code><br> 042 * Sixteen-bit Unicode Transformation Format, little-endian byte order.</li> 043 * <li><code>UTF-16</code><br> 044 * Sixteen-bit Unicode Transformation Format, byte order specified by a mandatory initial byte-order mark (either order 045 * accepted on input, big-endian used on output.)</li> 046 * </ul> 047 * 048 * This perhaps would best belong in the Commons Lang project. Even if a similar class is defined in Commons Lang, it is 049 * not foreseen that Commons Codec would be made to depend on Commons Lang. 050 * 051 * <p> 052 * This class is immutable and thread-safe. 053 * </p> 054 * 055 * @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a> 056 * @since 1.7 057 * @version $Id: Charsets.html 928559 2014-11-10 02:53:54Z ggregory $ 058 */ 059public class Charsets { 060 061 // 062 // This class should only contain Charset instances for required encodings. This guarantees that it will load 063 // correctly and without delay on all Java platforms. 064 // 065 066 /** 067 * Returns the given Charset or the default Charset if the given Charset is null. 068 * 069 * @param charset 070 * A charset or null. 071 * @return the given Charset or the default Charset if the given Charset is null 072 */ 073 public static Charset toCharset(final Charset charset) { 074 return charset == null ? Charset.defaultCharset() : charset; 075 } 076 077 /** 078 * Returns a Charset for the named charset. If the name is null, return the default Charset. 079 * 080 * @param charset 081 * The name of the requested charset, may be null. 082 * @return a Charset for the named charset 083 * @throws java.nio.charset.UnsupportedCharsetException 084 * If the named charset is unavailable 085 */ 086 public static Charset toCharset(final String charset) { 087 return charset == null ? Charset.defaultCharset() : Charset.forName(charset); 088 } 089 090 /** 091 * CharEncodingISO Latin Alphabet No. 1, a.k.a. ISO-LATIN-1. 092 * <p> 093 * Every implementation of the Java platform is required to support this character encoding. 094 * 095 * @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a> 096 * @deprecated Use Java 7's {@link java.nio.charset.StandardCharsets} 097 */ 098 @Deprecated 099 public static final Charset ISO_8859_1 = Charset.forName(CharEncoding.ISO_8859_1); 100 101 /** 102 * Seven-bit ASCII, also known as ISO646-US, also known as the Basic Latin block of the Unicode character set. 103 * <p> 104 * Every implementation of the Java platform is required to support this character encoding. 105 * 106 * @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a> 107 * @deprecated Use Java 7's {@link java.nio.charset.StandardCharsets} 108 */ 109 @Deprecated 110 public static final Charset US_ASCII = Charset.forName(CharEncoding.US_ASCII); 111 112 /** 113 * Sixteen-bit Unicode Transformation Format, The byte order specified by a mandatory initial byte-order mark 114 * (either order accepted on input, big-endian used on output) 115 * <p> 116 * Every implementation of the Java platform is required to support this character encoding. 117 * 118 * @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a> 119 * @deprecated Use Java 7's {@link java.nio.charset.StandardCharsets} 120 */ 121 @Deprecated 122 public static final Charset UTF_16 = Charset.forName(CharEncoding.UTF_16); 123 124 /** 125 * Sixteen-bit Unicode Transformation Format, big-endian byte order. 126 * <p> 127 * Every implementation of the Java platform is required to support this character encoding. 128 * 129 * @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a> 130 * @deprecated Use Java 7's {@link java.nio.charset.StandardCharsets} 131 */ 132 @Deprecated 133 public static final Charset UTF_16BE = Charset.forName(CharEncoding.UTF_16BE); 134 135 /** 136 * Sixteen-bit Unicode Transformation Format, little-endian byte order. 137 * <p> 138 * Every implementation of the Java platform is required to support this character encoding. 139 * 140 * @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a> 141 * @deprecated Use Java 7's {@link java.nio.charset.StandardCharsets} 142 */ 143 @Deprecated 144 public static final Charset UTF_16LE = Charset.forName(CharEncoding.UTF_16LE); 145 146 /** 147 * Eight-bit Unicode Transformation Format. 148 * <p> 149 * Every implementation of the Java platform is required to support this character encoding. 150 * 151 * @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a> 152 * @deprecated Use Java 7's {@link java.nio.charset.StandardCharsets} 153 */ 154 @Deprecated 155 public static final Charset UTF_8 = Charset.forName(CharEncoding.UTF_8); 156}