J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2000-2003 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package java.nio.channels; |
| 27 | |
| 28 | import java.io.IOException; |
| 29 | import java.io.Closeable; |
| 30 | |
| 31 | |
| 32 | /** |
| 33 | * A nexus for I/O operations. |
| 34 | * |
| 35 | * <p> A channel represents an open connection to an entity such as a hardware |
| 36 | * device, a file, a network socket, or a program component that is capable of |
| 37 | * performing one or more distinct I/O operations, for example reading or |
| 38 | * writing. |
| 39 | * |
| 40 | * <p> A channel is either open or closed. A channel is open upon creation, |
| 41 | * and once closed it remains closed. Once a channel is closed, any attempt to |
| 42 | * invoke an I/O operation upon it will cause a {@link ClosedChannelException} |
| 43 | * to be thrown. Whether or not a channel is open may be tested by invoking |
| 44 | * its {@link #isOpen isOpen} method. |
| 45 | * |
| 46 | * <p> Channels are, in general, intended to be safe for multithreaded access |
| 47 | * as described in the specifications of the interfaces and classes that extend |
| 48 | * and implement this interface. |
| 49 | * |
| 50 | * |
| 51 | * @author Mark Reinhold |
| 52 | * @author JSR-51 Expert Group |
| 53 | * @since 1.4 |
| 54 | */ |
| 55 | |
| 56 | public interface Channel extends Closeable { |
| 57 | |
| 58 | /** |
| 59 | * Tells whether or not this channel is open. </p> |
| 60 | * |
| 61 | * @return <tt>true</tt> if, and only if, this channel is open |
| 62 | */ |
| 63 | public boolean isOpen(); |
| 64 | |
| 65 | /** |
| 66 | * Closes this channel. |
| 67 | * |
| 68 | * <p> After a channel is closed, any further attempt to invoke I/O |
| 69 | * operations upon it will cause a {@link ClosedChannelException} to be |
| 70 | * thrown. |
| 71 | * |
| 72 | * <p> If this channel is already closed then invoking this method has no |
| 73 | * effect. |
| 74 | * |
| 75 | * <p> This method may be invoked at any time. If some other thread has |
| 76 | * already invoked it, however, then another invocation will block until |
| 77 | * the first invocation is complete, after which it will return without |
| 78 | * effect. </p> |
| 79 | * |
| 80 | * @throws IOException If an I/O error occurs |
| 81 | */ |
| 82 | public void close() throws IOException; |
| 83 | |
| 84 | } |