1 /* 2 * Copyright (c) 1997, 2007, 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 javax.net; 27 28 import java.io.IOException; 29 import java.net.InetAddress; 30 import java.net.ServerSocket; 31 import java.net.SocketException; 32 33 /** 34 * This class creates server sockets. It may be subclassed by other 35 * factories, which create particular types of server sockets. This 36 * provides a general framework for the addition of public socket-level 37 * functionality. It is the server side analogue of a socket factory, 38 * and similarly provides a way to capture a variety of policies related 39 * to the sockets being constructed. 40 * 41 * <P> Like socket factories, server Socket factory instances have 42 * methods used to create sockets. There is also an environment 43 * specific default server socket factory; frameworks will often use 44 * their own customized factory. 45 * 46 * @since 1.4 47 * @see SocketFactory 48 * 49 * @author David Brownell 50 */ 51 public abstract class ServerSocketFactory 52 { 53 // 54 // NOTE: JDK 1.1 bug in class GC, this can get collected 55 // even though it's always accessible via getDefault(). 56 // 57 private static ServerSocketFactory theFactory; 58 59 60 /** 61 * Creates a server socket factory. 62 */ 63 protected ServerSocketFactory() { /* NOTHING */ } 64 65 /** 66 * Returns a copy of the environment's default socket factory. 67 * 68 * @return the <code>ServerSocketFactory</code> 69 */ 70 public static ServerSocketFactory getDefault() 71 { 72 synchronized (ServerSocketFactory.class) { 73 if (theFactory == null) { 74 // 75 // Different implementations of this method could 76 // work rather differently. For example, driving 77 // this from a system property, or using a different 78 // implementation than JavaSoft's. 79 // 80 theFactory = new DefaultServerSocketFactory(); 81 } 82 } 83 84 return theFactory; 85 } 86 87 88 /** 89 * Returns an unbound server socket. The socket is configured with 90 * the socket options (such as accept timeout) given to this factory. 91 * 92 * @return the unbound socket 93 * @throws IOException if the socket cannot be created 94 * @see java.net.ServerSocket#bind(java.net.SocketAddress) 95 * @see java.net.ServerSocket#bind(java.net.SocketAddress, int) 96 * @see java.net.ServerSocket#ServerSocket() 97 */ 98 public ServerSocket createServerSocket() throws IOException { 99 throw new SocketException("Unbound server sockets not implemented"); 100 } 101 102 /** 103 * Returns a server socket bound to the specified port. 104 * The socket is configured with the socket options 105 * (such as accept timeout) given to this factory. 106 * <P> 107 * If there is a security manager, its <code>checkListen</code> 108 * method is called with the <code>port</code> argument as its 109 * argument to ensure the operation is allowed. This could result 110 * in a SecurityException. 111 * 112 * @param port the port to listen to 113 * @return the <code>ServerSocket</code> 114 * @throws IOException for networking errors 115 * @throws SecurityException if a security manager exists and its 116 * <code>checkListen</code> method doesn't allow the operation. 117 * @throws IllegalArgumentException if the port parameter is outside the 118 * specified range of valid port values, which is between 0 and 119 * 65535, inclusive. 120 * @see SecurityManager#checkListen 121 * @see java.net.ServerSocket#ServerSocket(int) 122 */ 123 public abstract ServerSocket createServerSocket(int port) 124 throws IOException; 125 126 127 /** 128 * Returns a server socket bound to the specified port, and uses the 129 * specified connection backlog. The socket is configured with 130 * the socket options (such as accept timeout) given to this factory. 131 * <P> 132 * The <code>backlog</code> argument must be a positive 133 * value greater than 0. If the value passed if equal or less 134 * than 0, then the default value will be assumed. 135 * <P> 136 * If there is a security manager, its <code>checkListen</code> 137 * method is called with the <code>port</code> argument as its 138 * argument to ensure the operation is allowed. This could result 139 * in a SecurityException. 140 * 141 * @param port the port to listen to 142 * @param backlog how many connections are queued 143 * @return the <code>ServerSocket</code> 144 * @throws IOException for networking errors 145 * @throws SecurityException if a security manager exists and its 146 * <code>checkListen</code> method doesn't allow the operation. 147 * @throws IllegalArgumentException if the port parameter is outside the 148 * specified range of valid port values, which is between 0 and 149 * 65535, inclusive. 150 * @see SecurityManager#checkListen 151 * @see java.net.ServerSocket#ServerSocket(int, int) 152 */ 153 public abstract ServerSocket 154 createServerSocket(int port, int backlog) 155 throws IOException; 156 157 158 /** 159 * Returns a server socket bound to the specified port, 160 * with a specified listen backlog and local IP. 161 * <P> 162 * The <code>ifAddress</code> argument can be used on a multi-homed 163 * host for a <code>ServerSocket</code> that will only accept connect 164 * requests to one of its addresses. If <code>ifAddress</code> is null, 165 * it will accept connections on all local addresses. The socket is 166 * configured with the socket options (such as accept timeout) given 167 * to this factory. 168 * <P> 169 * The <code>backlog</code> argument must be a positive 170 * value greater than 0. If the value passed if equal or less 171 * than 0, then the default value will be assumed. 172 * <P> 173 * If there is a security manager, its <code>checkListen</code> 174 * method is called with the <code>port</code> argument as its 175 * argument to ensure the operation is allowed. This could result 176 * in a SecurityException. 177 * 178 * @param port the port to listen to 179 * @param backlog how many connections are queued 180 * @param ifAddress the network interface address to use 181 * @return the <code>ServerSocket</code> 182 * @throws IOException for networking errors 183 * @throws SecurityException if a security manager exists and its 184 * <code>checkListen</code> method doesn't allow the operation. 185 * @throws IllegalArgumentException if the port parameter is outside the 186 * specified range of valid port values, which is between 0 and 187 * 65535, inclusive. 188 * @see SecurityManager#checkListen 189 * @see java.net.ServerSocket#ServerSocket(int, int, java.net.InetAddress) 190 */ 191 public abstract ServerSocket 192 createServerSocket(int port, int backlog, InetAddress ifAddress) 193 throws IOException; 194 } 195 196 197 // 198 // The default factory has NO intelligence. In fact it's not clear 199 // what sort of intelligence servers need; the onus is on clients, 200 // who have to know how to tunnel etc. 201 // 202 class DefaultServerSocketFactory extends ServerSocketFactory { 203 204 DefaultServerSocketFactory() 205 { 206 /* NOTHING */ 207 } 208 209 public ServerSocket createServerSocket() 210 throws IOException 211 { 212 return new ServerSocket(); 213 } 214 215 public ServerSocket createServerSocket(int port) 216 throws IOException 217 { 218 return new ServerSocket(port); 219 } 220 221 public ServerSocket createServerSocket(int port, int backlog) 222 throws IOException 223 { 224 return new ServerSocket(port, backlog); 225 } 226 227 public ServerSocket 228 createServerSocket(int port, int backlog, InetAddress ifAddress) 229 throws IOException 230 { 231 return new ServerSocket(port, backlog, ifAddress); 232 } 233 } 234
