| /* |
| * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /** |
| * Defines buffers, which are containers for data, and provides an |
| * overview of the other NIO packages. |
| * |
| * |
| * <p> The central abstractions of the NIO APIs are: </p> |
| * |
| * <ul> |
| * |
| * <li><p> <a href="#buffers"><i>Buffers</i></a>, which are containers for data; |
| * </p></li> |
| * |
| * <li><p> <a |
| * href="charset/package-summary.html"><i>Charsets</i></a> and their |
| * associated <i>decoders</i> and <i>encoders</i>, <br> which |
| * translate between bytes and Unicode characters; </p></li> |
| * |
| * <li><p> <a |
| * href="channels/package-summary.html"><i>Channels</i></a> of |
| * various types, which represent connections <br> to entities |
| * capable of performing I/O operations; and </p></li> |
| * |
| * <li><p> <i>Selectors</i> and <i>selection keys</i>, which |
| * together with <br> <i>selectable channels</i> define a <a |
| * href="channels/package-summary.html#multiplex">multiplexed, |
| * non-blocking <br> I/O</a> facility. </p></li> |
| * |
| * </ul> |
| * |
| * <p> The {@code java.nio} package defines the buffer classes, which |
| * are used throughout the NIO APIs. The charset API is defined in |
| * the {@link java.nio.charset} package, and the channel and selector |
| * APIs are defined in the {@link java.nio.channels} package. Each of |
| * these subpackages has its own service-provider (SPI) subpackage, |
| * the contents of which can be used to extend the platform's default |
| * implementations or to construct alternative implementations. |
| * |
| * <a id="buffers"> </a> |
| * |
| * <table class="striped" style="margin-left:2em; text-align:left"> |
| * <caption style="display:none">Description of the various buffers</caption> |
| * <thead> |
| * <tr><th scope="col">Buffers</th> |
| * <th scope="col">Description</th></tr> |
| * </thead> |
| * <tbody> |
| * <tr><th scope="row">{@link java.nio.Buffer}</th> |
| * <td>Position, limit, and capacity; |
| * clear, flip, rewind, and mark/reset</td></tr> |
| * <tr><th scope="row"> |
| * <span style="padding-left:1em">{@link java.nio.ByteBuffer}</span></th> |
| * <td>Get/put, compact, views; allocate, wrap</td></tr> |
| * <tr><th scope="row"> |
| * <span style="padding-left:2em">{@link java.nio.MappedByteBuffer}</span></th> |
| * <td>A byte buffer mapped to a file</td></tr> |
| * <tr><th scope="row"> |
| * <span style="padding-left:1em">{@link java.nio.CharBuffer}</span></th> |
| * <td>Get/put, compact; allocate, wrap</td></tr> |
| * <tr><th scope="row"> |
| * <span style="padding-left:1em">{@link java.nio.DoubleBuffer}</span></th> |
| * <td>Get/put, compact; allocate, wrap</td></tr> |
| * <tr><th scope="row"> |
| * <span style="padding-left:1em">{@link java.nio.FloatBuffer}</span></th> |
| * <td>Get/put, compact; allocate, wrap</td></tr> |
| * <tr><th scope="row"> |
| * <span style="padding-left:1em">{@link java.nio.IntBuffer}</span></th> |
| * <td>Get/put, compact; allocate, wrap</td></tr> |
| * <tr><th scope="row"> |
| * <span style="padding-left:1em">{@link java.nio.LongBuffer}</span></th> |
| * <td>Get/put, compact; allocate, wrap</td></tr> |
| * <tr><th scope="row"> |
| * <span style="padding-left:1em">{@link java.nio.ShortBuffer}</span></th> |
| * <td>Get/put, compact; allocate, wrap</td></tr> |
| * <tr><th scope="row">{@link java.nio.ByteOrder}</th> |
| * <td>Typesafe enumeration for byte orders</td></tr> |
| * </tbody> |
| * </table> |
| * |
| * <p> A <i>buffer</i> is a container for a fixed amount of data of a |
| * specific primitive type. In addition to its content a buffer has a |
| * <i>position</i>, which is the index of the next element to be read |
| * or written, and a <i>limit</i>, which is the index of the first |
| * element that should not be read or written. The base {@link |
| * java.nio.Buffer} class defines these properties as well as methods |
| * for <i>clearing</i>, <i>flipping</i>, and <i>rewinding</i>, for |
| * <i>marking</i> the current position, and for <i>resetting</i> the |
| * position to the previous mark. |
| * |
| * <p> There is a buffer class for each non-boolean primitive type. |
| * Each class defines a family of <i>get</i> and <i>put</i> methods |
| * for moving data out of and in to a buffer, methods for |
| * <i>compacting</i>, <i>duplicating</i>, and <i>slicing</i> a buffer, |
| * and static methods for <i>allocating</i> a new buffer as well as |
| * for <i>wrapping</i> an existing array into a buffer. |
| * |
| * <p> Byte buffers are distinguished in that they can be used as the |
| * sources and targets of I/O operations. They also support several |
| * features not found in the other buffer classes: |
| * |
| * <ul> |
| * |
| * <li><p> A byte buffer can be allocated as a <a |
| * href="ByteBuffer.html#direct"> <i>direct</i></a> buffer, in which |
| * case the Java virtual machine will make a best effort to perform |
| * native I/O operations directly upon it. </p></li> |
| * |
| * <li><p> A byte buffer can be created by {@link |
| * java.nio.channels.FileChannel#map <i>mapping</i>} a region of a |
| * file directly into memory, in which case a few additional |
| * file-related operations defined in the {@link |
| * java.nio.MappedByteBuffer} class are available. </p></li> |
| * |
| * <li><p> A byte buffer provides access to its content as either a |
| * heterogeneous or homogeneous sequence of <a |
| * href="ByteBuffer.html#bin"><i>binary data</i></a> of any |
| * non-boolean primitive type, in either big-endian or little-endian |
| * <a href="ByteOrder.html">byte order</a>. </p></li> |
| * |
| * </ul> |
| * |
| * <p> Unless otherwise noted, passing a {@code null} argument to a |
| * constructor or method in any class or interface in this package |
| * will cause a {@link java.lang.NullPointerException |
| * NullPointerException} to be thrown. |
| * |
| * @since 1.4 |
| * @author Mark Reinhold |
| * @author JSR-51 Expert Group |
| */ |
| package java.nio; |