2362N/A * Copyright (c) 2007, 2009, Oracle and/or its affiliates. All rights reserved. 893N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 893N/A * This code is free software; you can redistribute it and/or modify it 893N/A * under the terms of the GNU General Public License version 2 only, as 2362N/A * published by the Free Software Foundation. Oracle designates this 893N/A * particular file as subject to the "Classpath" exception as provided 2362N/A * by Oracle in the LICENSE file that accompanied this code. 893N/A * This code is distributed in the hope that it will be useful, but WITHOUT 893N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 893N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 893N/A * version 2 for more details (a copy is included in the LICENSE file that 893N/A * accompanied this code). 893N/A * You should have received a copy of the GNU General Public License version 893N/A * 2 along with this work; if not, write to the Free Software Foundation, 893N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 2362N/A * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2362N/A * or visit www.oracle.com if you need additional information or have any 893N/A * An asynchronous channel that can read and write bytes. 893N/A * <p> Some channels may not allow more than one read or write to be outstanding 893N/A * at any given time. If a thread invokes a read method before a previous read 893N/A * operation has completed then a {@link ReadPendingException} will be thrown. 893N/A * Similarly, if a write method is invoked before a previous write has completed 893N/A * then {@link WritePendingException} is thrown. Whether or not other kinds of 893N/A * I/O operations may proceed concurrently with a read operation depends upon 893N/A * the type of the channel. 893N/A * <p> Note that {@link java.nio.ByteBuffer ByteBuffers} are not safe for use by 893N/A * multiple concurrent threads. When a read or write operation is initiated then 893N/A * care must be taken to ensure that the buffer is not accessed until the 893N/A * @see Channels#newInputStream(AsynchronousByteChannel) 893N/A * @see Channels#newOutputStream(AsynchronousByteChannel) 893N/A * Reads a sequence of bytes from this channel into the given buffer. 1580N/A * <p> This method initiates an asynchronous read operation to read a 1580N/A * sequence of bytes from this channel into the given buffer. The {@code 1580N/A * handler} parameter is a completion handler that is invoked when the read 1580N/A * operation completes (or fails). The result passed to the completion 1580N/A * handler is the number of bytes read or {@code -1} if no bytes could be 1580N/A * read because the channel has reached end-of-stream. 1580N/A * <p> The read operation may read up to <i>r</i> bytes from the channel, 1580N/A * where <i>r</i> is the number of bytes remaining in the buffer, that is, 1580N/A * {@code dst.remaining()} at the time that the read is attempted. Where 1580N/A * <i>r</i> is 0, the read operation completes immediately with a result of 1580N/A * {@code 0} without initiating an I/O operation. 893N/A * <p> Suppose that a byte sequence of length <i>n</i> is read, where 893N/A * <tt>0</tt> <tt><</tt> <i>n</i> <tt><=</tt> <i>r</i>. 893N/A * This byte sequence will be transferred into the buffer so that the first 893N/A * byte in the sequence is at index <i>p</i> and the last byte is at index 893N/A * <i>p</i> <tt>+</tt> <i>n</i> <tt>-</tt> <tt>1</tt>, 893N/A * where <i>p</i> is the buffer's position at the moment the read is 893N/A * performed. Upon completion the buffer's position will be equal to 893N/A * <i>p</i> <tt>+</tt> <i>n</i>; its limit will not have changed. 893N/A * <p> Buffers are not safe for use by multiple concurrent threads so care 1580N/A * should be taken to not access the buffer until the operation has 893N/A * <p> This method may be invoked at any time. Some channel types may not 893N/A * allow more than one read to be outstanding at any given time. If a thread 893N/A * initiates a read operation before a previous read operation has 893N/A * completed then a {@link ReadPendingException} will be thrown. 893N/A * The buffer into which bytes are to be transferred 893N/A * The object to attach to the I/O operation; can be {@code null} 893N/A * @throws IllegalArgumentException 893N/A * If the buffer is read-only 893N/A * @throws ReadPendingException 893N/A * If the channel does not allow more than one read to be outstanding 893N/A * and a previous read has not completed 1580N/A * @throws ShutdownChannelGroupException 1580N/A * If the channel is associated with a {@link AsynchronousChannelGroup 1580N/A * group} that has terminated 893N/A * Reads a sequence of bytes from this channel into the given buffer. 1580N/A * <p> This method initiates an asynchronous read operation to read a 1580N/A * sequence of bytes from this channel into the given buffer. The method 1580N/A * behaves in exactly the same manner as the {@link 1580N/A * #read(ByteBuffer,Object,CompletionHandler) 1580N/A * read(ByteBuffer,Object,CompletionHandler)} method except that instead 1580N/A * of specifying a completion handler, this method returns a {@code Future} 1580N/A * representing the pending result. The {@code Future}'s {@link Future#get() 1580N/A * get} method returns the number of bytes read or {@code -1} if no bytes 1580N/A * could be read because the channel has reached end-of-stream. 893N/A * The buffer into which bytes are to be transferred 893N/A * @return A Future representing the result of the operation 893N/A * @throws IllegalArgumentException 893N/A * If the buffer is read-only 893N/A * @throws ReadPendingException 893N/A * If the channel does not allow more than one read to be outstanding 893N/A * and a previous read has not completed 893N/A * Writes a sequence of bytes to this channel from the given buffer. 1580N/A * <p> This method initiates an asynchronous write operation to write a 1580N/A * sequence of bytes to this channel from the given buffer. The {@code 1580N/A * handler} parameter is a completion handler that is invoked when the write 1580N/A * operation completes (or fails). The result passed to the completion 1580N/A * handler is the number of bytes written. 1580N/A * <p> The write operation may write up to <i>r</i> bytes to the channel, 1580N/A * where <i>r</i> is the number of bytes remaining in the buffer, that is, 1580N/A * {@code src.remaining()} at the time that the write is attempted. Where 1580N/A * <i>r</i> is 0, the write operation completes immediately with a result of 1580N/A * {@code 0} without initiating an I/O operation. 893N/A * <p> Suppose that a byte sequence of length <i>n</i> is written, where 893N/A * <tt>0</tt> <tt><</tt> <i>n</i> <tt><=</tt> <i>r</i>. 893N/A * This byte sequence will be transferred from the buffer starting at index 893N/A * <i>p</i>, where <i>p</i> is the buffer's position at the moment the 893N/A * write is performed; the index of the last byte written will be 893N/A * <i>p</i> <tt>+</tt> <i>n</i> <tt>-</tt> <tt>1</tt>. 893N/A * Upon completion the buffer's position will be equal to 893N/A * <i>p</i> <tt>+</tt> <i>n</i>; its limit will not have changed. 893N/A * <p> Buffers are not safe for use by multiple concurrent threads so care 1580N/A * should be taken to not access the buffer until the operation has 893N/A * <p> This method may be invoked at any time. Some channel types may not 893N/A * allow more than one write to be outstanding at any given time. If a thread 893N/A * initiates a write operation before a previous write operation has 893N/A * completed then a {@link WritePendingException} will be thrown. 893N/A * The buffer from which bytes are to be retrieved 893N/A * The object to attach to the I/O operation; can be {@code null} 1580N/A * The completion handler object 893N/A * @throws WritePendingException 893N/A * If the channel does not allow more than one write to be outstanding 893N/A * and a previous write has not completed 1580N/A * @throws ShutdownChannelGroupException 1580N/A * If the channel is associated with a {@link AsynchronousChannelGroup 1580N/A * group} that has terminated 893N/A * Writes a sequence of bytes to this channel from the given buffer. 1580N/A * <p> This method initiates an asynchronous write operation to write a 1580N/A * sequence of bytes to this channel from the given buffer. The method 1580N/A * behaves in exactly the same manner as the {@link 1580N/A * #write(ByteBuffer,Object,CompletionHandler) 1580N/A * write(ByteBuffer,Object,CompletionHandler)} method except that instead 1580N/A * of specifying a completion handler, this method returns a {@code Future} 1580N/A * representing the pending result. The {@code Future}'s {@link Future#get() 1580N/A * get} method returns the number of bytes written. 893N/A * The buffer from which bytes are to be retrieved 893N/A * @return A Future representing the result of the operation 893N/A * @throws WritePendingException 893N/A * If the channel does not allow more than one write to be outstanding 893N/A * and a previous write has not completed