1 /* 2 * Copyright (c) 2001, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 /** 27 * Defines charsets, decoders, and encoders, for translating between 28 * bytes and Unicode characters. 29 * 30 * <table class="striped" style="margin-left:2em; text-align:left"> 31 * <caption style="display:none">Summary of charsets, decoders, and encoders in this package</caption> 32 * <thead> 33 * <tr><th scope="col">Class name</th> 34 * <th scope="col">Description 35 * </thead> 36 * <tbody> 37 * <tr><th scope="row">{@link java.nio.charset.Charset}</th> 38 * <td>A named mapping between characters and bytes</td></tr> 39 * <tr><th scope="row">{@link java.nio.charset.CharsetDecoder}</th> 40 * <td>Decodes bytes into characters</td></tr> 41 * <tr><th scope="row">{@link java.nio.charset.CharsetEncoder}</th> 42 * <td>Encodes characters into bytes</td></tr> 43 * <tr><th scope="row">{@link java.nio.charset.CoderResult}</th> 44 * <td>Describes coder results</td></tr> 45 * <tr><th scope="row">{@link java.nio.charset.CodingErrorAction}</th> 46 * <td>Describes actions to take when coding errors are detected</td></tr> 47 * </tbody> 48 * </table> 49 * 50 * <p> A <i>charset</i> is named mapping between sequences of 51 * sixteen-bit Unicode characters and sequences of bytes, in the sense 52 * defined in <a 53 * href="http://www.ietf.org/rfc/rfc2278.txt"><i>RFC 2278</i></a>. 54 * A <i>decoder</i> is an engine which transforms bytes in a specific 55 * charset into characters, and an <i>encoder</i> is an engine which 56 * transforms characters into bytes. Encoders and decoders operate on 57 * byte and character buffers. They are collectively referred to as 58 * <i>coders</i>. 59 * 60 * <p> The {@link java.nio.charset.Charset} class defines methods for 61 * creating coders for a given charset and for retrieving the various 62 * names associated with a charset. It also defines static methods 63 * for testing whether a particular charset is supported, for locating 64 * charset instances by name, and for constructing a map that contains 65 * every charset for which support is available in the current Java 66 * virtual machine. 67 * 68 * <p> Most users will not use these classes directly; instead they 69 * will use the existing charset-related constructors and methods in 70 * the {@link java.lang.String} class, together with the existing 71 * {@link java.io.InputStreamReader} and {@link 72 * java.io.OutputStreamWriter} classes, all of whose implementations 73 * have been reworked to make use of the charset facilities defined in 74 * this package. A small number of changes have been made to the 75 * {@link java.io.InputStreamReader} and {@link 76 * java.io.OutputStreamWriter} classes in order to allow explicit 77 * charset objects to be specified in the construction of instances of 78 * those classes. 79 * 80 * <p> Support for new charsets can be made available via the 81 * interface defined in the {@link 82 * java.nio.charset.spi.CharsetProvider} class in the {@link 83 * java.nio.charset.spi} package. 84 * 85 * <p> Unless otherwise noted, passing a {@code null} argument to a 86 * constructor or method in any class or interface in this package 87 * will cause a {@link java.lang.NullPointerException 88 * NullPointerException} to be thrown. 89 * 90 * 91 * @since 1.4 92 * @author Mark Reinhold 93 * @author JSR-51 Expert Group 94 */ 95 package java.nio.charset; 96