J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1997-2007 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 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 | } |