1 /* 2 * Copyright (c) 2000, 2005, 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 package java.nio.channels; 27 28 import java.io.IOException; 29 import java.nio.ByteBuffer; 30 31 32 /** 33 * A channel that can write bytes. 34 * 35 * <p> Only one write operation upon a writable channel may be in progress at 36 * any given time. If one thread initiates a write operation upon a channel 37 * then any other thread that attempts to initiate another write operation will 38 * block until the first operation is complete. Whether or not other kinds of 39 * I/O operations may proceed concurrently with a write operation depends upon 40 * the type of the channel. </p> 41 * 42 * 43 * @author Mark Reinhold 44 * @author JSR-51 Expert Group 45 * @since 1.4 46 */ 47 48 public interface WritableByteChannel 49 extends Channel 50 { 51 52 /** 53 * Writes a sequence of bytes to this channel from the given buffer. 54 * 55 * <p> An attempt is made to write up to <i>r</i> bytes to the channel, 56 * where <i>r</i> is the number of bytes remaining in the buffer, that is, 57 * {@code src.remaining()}, at the moment this method is invoked. 58 * 59 * <p> Suppose that a byte sequence of length <i>n</i> is written, where 60 * {@code 0} {@code <=} <i>n</i> {@code <=} <i>r</i>. 61 * This byte sequence will be transferred from the buffer starting at index 62 * <i>p</i>, where <i>p</i> is the buffer's position at the moment this 63 * method is invoked; the index of the last byte written will be 64 * <i>p</i> {@code +} <i>n</i> {@code -} {@code 1}. 65 * Upon return the buffer's position will be equal to 66 * <i>p</i> {@code +} <i>n</i>; its limit will not have changed. 67 * 68 * <p> Unless otherwise specified, a write operation will return only after 69 * writing all of the <i>r</i> requested bytes. Some types of channels, 70 * depending upon their state, may write only some of the bytes or possibly 71 * none at all. A socket channel in non-blocking mode, for example, cannot 72 * write any more bytes than are free in the socket's output buffer. 73 * 74 * <p> This method may be invoked at any time. If another thread has 75 * already initiated a write operation upon this channel, however, then an 76 * invocation of this method will block until the first operation is 77 * complete. </p> 78 * 79 * @param src 80 * The buffer from which bytes are to be retrieved 81 * 82 * @return The number of bytes written, possibly zero 83 * 84 * @throws NonWritableChannelException 85 * If this channel was not opened for writing 86 * 87 * @throws ClosedChannelException 88 * If this channel is closed 89 * 90 * @throws AsynchronousCloseException 91 * If another thread closes this channel 92 * while the write operation is in progress 93 * 94 * @throws ClosedByInterruptException 95 * If another thread interrupts the current thread 96 * while the write operation is in progress, thereby 97 * closing the channel and setting the current thread's 98 * interrupt status 99 * 100 * @throws IOException 101 * If some other I/O error occurs 102 */ write(ByteBuffer src)103 public int write(ByteBuffer src) throws IOException; 104 105 } 106