/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package org.apache.commons.compress.utils;
import java.nio.charset.Charset;
/**
* Charsets required of every implementation of the Java platform.
*
* From the Java documentation <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard
* charsets</a>:
* <p>
* <cite>Every implementation of the Java platform is required to support the following character encodings. Consult the
* release documentation for your implementation to see if any other encodings are supported. Consult the release
* documentation for your implementation to see if any other encodings are supported. </cite>
* </p>
*
* <dl>
* <dt><code>US-ASCII</code></dt>
* <dd>Seven-bit ASCII, a.k.a. ISO646-US, a.k.a. the Basic Latin block of the Unicode character set.</dd>
* <dt><code>ISO-8859-1</code></dt>
* <dd>ISO Latin Alphabet No. 1, a.k.a. ISO-LATIN-1.</dd>
* <dt><code>UTF-8</code></dt>
* <dd>Eight-bit Unicode Transformation Format.</dd>
* <dt><code>UTF-16BE</code></dt>
* <dd>Sixteen-bit Unicode Transformation Format, big-endian byte order.</dd>
* <dt><code>UTF-16LE</code></dt>
* <dd>Sixteen-bit Unicode Transformation Format, little-endian byte order.</dd>
* <dt><code>UTF-16</code></dt>
* <dd>Sixteen-bit Unicode Transformation Format, byte order specified by a mandatory initial byte-order mark (either order
* accepted on input, big-endian used on output.)</dd>
* </dl>
*
* <p>This class best belongs in the Commons Lang or IO project. Even if a similar class is defined in another Commons
* component, it is not foreseen that Commons Compress would be made to depend on another Commons component.</p>
*
* @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
* @since 1.4
* @version $Id$
*/
public class Charsets {
//
// This class should only contain Charset instances for required encodings. This guarantees that it will load correctly and
// without delay on all Java platforms.
//
/**
* Returns the given Charset or the default Charset if the given Charset is null.
*
* @param charset
* A charset or null.
* @return the given Charset or the default Charset if the given Charset is null
*/
public static Charset toCharset(final Charset charset) {
return charset == null ? Charset.defaultCharset() : charset;
}
/**
* Returns a Charset for the named charset. If the name is null, return the default Charset.
*
* @param charset
* The name of the requested charset, may be null.
* @return a Charset for the named charset
* @throws java.nio.charset.UnsupportedCharsetException
* If the named charset is unavailable
* @throws java.nio.charset.IllegalCharsetNameException
* If the given charset name is illegal
*/
public static Charset toCharset(final String charset) {
return charset == null ? Charset.defaultCharset() : Charset.forName(charset);
}
/**
* CharsetNamesISO Latin Alphabet No. 1, a.k.a. ISO-LATIN-1.
* <p>
* Every implementation of the Java platform is required to support this character encoding.
* </p>
*
* @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
*/
public static final Charset ISO_8859_1 = Charset.forName(CharsetNames.ISO_8859_1);
/**
* <p>
* Seven-bit ASCII, also known as ISO646-US, also known as the Basic Latin block of the Unicode character set.
* </p>
* <p>
* Every implementation of the Java platform is required to support this character encoding.
* </p>
*
* @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
*/
public static final Charset US_ASCII = Charset.forName(CharsetNames.US_ASCII);
/**
* <p>
* Sixteen-bit Unicode Transformation Format, The byte order specified by a mandatory initial byte-order mark
* (either order accepted on input, big-endian used on output)
* </p>
* <p>
* Every implementation of the Java platform is required to support this character encoding.
* </p>
*
* @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
*/
public static final Charset UTF_16 = Charset.forName(CharsetNames.UTF_16);
/**
* <p>
* Sixteen-bit Unicode Transformation Format, big-endian byte order.
* </p>
* <p>
* Every implementation of the Java platform is required to support this character encoding.
* </p>
*
* @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
*/
public static final Charset UTF_16BE = Charset.forName(CharsetNames.UTF_16BE);
/**
* <p>
* Sixteen-bit Unicode Transformation Format, little-endian byte order.
* </p>
* <p>
* Every implementation of the Java platform is required to support this character encoding.
* </p>
*
* @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
*/
public static final Charset UTF_16LE = Charset.forName(CharsetNames.UTF_16LE);
/**
* <p>
* Eight-bit Unicode Transformation Format.
* </p>
* <p>
* Every implementation of the Java platform is required to support this character encoding.
* </p>
*
* @see <a href="http://docs.oracle.com/javase/6/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
*/
public static final Charset UTF_8 = Charset.forName(CharsetNames.UTF_8);
}