001/* SelectableChannel.java -- 002 Copyright (C) 2002 Free Software Foundation, Inc. 003 004This file is part of GNU Classpath. 005 006GNU Classpath is free software; you can redistribute it and/or modify 007it under the terms of the GNU General Public License as published by 008the Free Software Foundation; either version 2, or (at your option) 009any later version. 010 011GNU Classpath is distributed in the hope that it will be useful, but 012WITHOUT ANY WARRANTY; without even the implied warranty of 013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014General Public License for more details. 015 016You should have received a copy of the GNU General Public License 017along with GNU Classpath; see the file COPYING. If not, write to the 018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 01902110-1301 USA. 020 021Linking this library statically or dynamically with other modules is 022making a combined work based on this library. Thus, the terms and 023conditions of the GNU General Public License cover the whole 024combination. 025 026As a special exception, the copyright holders of this library give you 027permission to link this library with independent modules to produce an 028executable, regardless of the license terms of these independent 029modules, and to copy and distribute the resulting executable under 030terms of your choice, provided that you also meet, for each linked 031independent module, the terms and conditions of the license of that 032module. An independent module is a module which is not derived from 033or based on this library. If you modify this library, you may extend 034this exception to your version of the library, but you are not 035obligated to do so. If you do not wish to do so, delete this 036exception statement from your version. */ 037 038package java.nio.channels; 039 040import java.io.IOException; 041import java.nio.channels.spi.AbstractInterruptibleChannel; 042import java.nio.channels.spi.SelectorProvider; 043 044 045/** 046 * @author Michael Koch 047 * @since 1.4 048 */ 049public abstract class SelectableChannel extends AbstractInterruptibleChannel 050{ 051 /** 052 * Initializes the channel. 053 */ 054 protected SelectableChannel() 055 { 056 } 057 058 /** 059 * Returns the lock of this channel. 060 */ 061 public abstract Object blockingLock(); 062 063 /** 064 * Adjusts this channel's blocking mode. 065 * 066 * @exception ClosedChannelException If this channel is closed. 067 * @exception IllegalBlockingModeException If block is true and this channel 068 * is registered with one or more selectors. 069 * @exception IOException If an error occurs. 070 */ 071 public abstract SelectableChannel configureBlocking(boolean block) 072 throws IOException; 073 074 /** 075 * Tells whether this channel is blocking or not. 076 */ 077 public abstract boolean isBlocking(); 078 079 /** 080 * Tells whether or not this channel is currently registered with 081 * any selectors. 082 */ 083 public abstract boolean isRegistered(); 084 085 /** 086 * Retrieves the key representing the channel's registration with 087 * the given selector. 088 */ 089 public abstract SelectionKey keyFor(Selector sel); 090 091 /** 092 * Returns the provider that created this channel. 093 */ 094 public abstract SelectorProvider provider(); 095 096 /** 097 * Registers this channel with the given selector, 098 * returning a selection key. 099 * 100 * @exception CancelledKeyException If this channel is currently registered 101 * with the given selector but the corresponding key has already been cancelled 102 * @exception ClosedChannelException If this channel is closed. 103 * @exception IllegalArgumentException If a bit in ops does not correspond 104 * to an operation that is supported by this channel, that is, if 105 * set & ~validOps() != 0. 106 * @exception IllegalBlockingModeException If block is true and this channel 107 * is registered with one or more selectors. 108 * @exception IllegalSelectorException If this channel was not created by 109 * the same provider as the given selector. 110 */ 111 public final SelectionKey register(Selector sel, int ops) 112 throws ClosedChannelException 113 { 114 return register(sel, ops, null); 115 } 116 117 /** 118 * Registers this channel with the given selector, 119 * returning a selection key. 120 * 121 * @exception CancelledKeyException If this channel is currently registered 122 * with the given selector but the corresponding key has already been 123 * cancelled. 124 * @exception ClosedChannelException If this channel is closed. 125 * @exception IllegalArgumentException If a bit in ops does not correspond 126 * to an operation that is supported by this channel, that is, if 127 * set & ~validOps() != 0. 128 * @exception IllegalBlockingModeException If block is true and this channel 129 * is registered with one or more selectors. 130 * @exception IllegalSelectorException If this channel was not created by 131 * the same provider as the given selector. 132 */ 133 public abstract SelectionKey register(Selector sel, int ops, Object att) 134 throws ClosedChannelException; 135 136 /** 137 * Returns a set of valid operations on this channel. 138 */ 139 public abstract int validOps(); 140}