001/* SocketFactory.java -- factory for client sockets.
002   Copyright (C) 2004 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
038
039package javax.net;
040
041import java.io.IOException;
042
043import java.net.InetAddress;
044import java.net.Socket;
045import java.net.UnknownHostException;
046
047import java.security.Security;
048
049/**
050 * A factory for client sockets. The purpose of this class is to serve
051 * as the superclass of server socket factories that produce client
052 * sockets of a particular type, such as <i>Secure Socket Layer</i>
053 * (<b>SSL</b>) sockets.
054 *
055 * @author Casey Marshall (rsdio@metastatic.org)
056 */
057public abstract class SocketFactory
058{
059
060  // Constructor.
061  // -------------------------------------------------------------------
062
063  /**
064   * Default 0-arguments constructor.
065   */
066  protected SocketFactory()
067  {
068    super();
069  }
070
071  // Class methods.
072  // -------------------------------------------------------------------
073
074  /**
075   * Returns the default socket factory. The type of factory
076   * returned may depend upon the installation.
077   *
078   * @return The default socket factory.
079   */
080  public static synchronized SocketFactory getDefault()
081  {
082    try
083      {
084        String s = Security.getProperty("gnu.defaultSocketFactory");
085        if (s != null)
086          {
087            Class c = Class.forName(s);
088            return (SocketFactory) c.newInstance();
089          }
090      }
091    catch (Exception e)
092      {
093      }
094    return new VanillaSocketFactory();
095  }
096
097  // Instance methods.
098  // -------------------------------------------------------------------
099
100  /**
101   * Returns an unbound client socket.
102   *
103   * @return The new, unbound socket.
104   */
105  public Socket createSocket() throws IOException
106  {
107    throw new UnsupportedOperationException();
108  }
109
110  /**
111   * Creates a socket connected to a given host on a given port.
112   *
113   * @param host The hostname to connect to.
114   * @param port The port on <i>host</i> to connect to.
115   * @return A socket connected to <i>host</i> on <i>port</i>.
116   * @throws IOException If a network error occurs.
117   * @throws UnknownHostException If <i>host</i> cannot be resolved.
118   */
119  public abstract Socket createSocket(String host, int port) throws IOException, UnknownHostException;
120
121  /**
122   * Creates a socket connected to a given host on a given port,
123   * connecting locally to the interface with the given address and port.
124   *
125   * @param host The hostname to connect to.
126   * @param port The port on <i>host</i> to connect to.
127   * @param localHost The address of the local interface to bind to.
128   * @param localPort The local port to bind to.
129   * @return A socket connected to <i>host</i> on <i>port</i>.
130   * @throws IOException If a network error occurs.
131   * @throws UnknownHostException If <i>host</i> cannot be resolved.
132   */
133  public abstract Socket createSocket(String host, int port, InetAddress localHost, int localPort) throws IOException, UnknownHostException;
134
135  /**
136   * Creates a socket connected to a given host on a given port.
137   *
138   * @param host The host address to connect to.
139   * @param port The port on <i>host</i> to connect to.
140   * @return A socket connected to <i>host</i> on <i>port</i>.
141   * @throws IOException If a network error occurs.
142   */
143  public abstract Socket createSocket(InetAddress host, int port) throws IOException;
144
145  /**
146   * Creates a socket connected to a given host on a given port,
147   * connecting locally to the interface with the given address and port.
148   *
149   * @param host The host address  to connect to.
150   * @param port The port on <i>host</i> to connect to.
151   * @param localHost The address of the local interface to bind to.
152   * @param localPort The local port to bind to.
153   * @return A socket connected to <i>host</i> on <i>port</i>.
154   * @throws IOException If a network error occurs.
155   */
156  public abstract Socket createSocket(InetAddress hast, int port, InetAddress localHost, int localPort) throws IOException;
157}