001/* ProxySelector.java -- A proxy selector class
002   Copyright (C) 2006  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.net;
039
040import gnu.java.net.DefaultProxySelector;
041
042import java.io.IOException;
043import java.util.List;
044
045/**
046 * Class for handling proxies for different connections.
047 * 
048 * @since 1.5
049 */
050public abstract class ProxySelector
051{
052  /**
053   * Default proxy selector.
054   */
055  private static ProxySelector defaultSelector = new DefaultProxySelector();
056
057  /**
058   * Creates a new <code>ProxySelector</code> object.
059   */
060  public ProxySelector()
061  {
062    // Do nothing here.
063  }
064
065  /**
066   * Returns the default proxy selector.
067   *
068   * @return the default proxy selector
069   *
070   * @throws SecurityException If a security manager is installed and it
071   * denies NetPermission("getProxySelector")
072   */
073  public static ProxySelector getDefault()
074  {
075    SecurityManager sm = System.getSecurityManager();
076
077    if (sm != null)
078      sm.checkPermission(new NetPermission("getProxySelector"));
079
080    return defaultSelector;
081  }
082
083  /**
084   * Sets the default proxy selector.
085   *
086   * @param selector the defualt proxy selector
087   *
088   * @throws SecurityException If a security manager is installed and it
089   * denies NetPermission("setProxySelector")
090   */
091  public static void setDefault(ProxySelector selector)
092  {
093    SecurityManager sm = System.getSecurityManager();
094
095    if (sm != null)
096      sm.checkPermission(new NetPermission("setProxySelector"));
097
098    defaultSelector = selector;
099  }
100
101  /**
102   * Signals to the selector that a proxy was no available.
103   * 
104   * @throws IllegalArgumentException If one argument is null
105   */
106  public abstract void connectFailed(URI uri, SocketAddress address,
107                                     IOException exception);
108
109  /**
110   * Returns the list of proxy settings for a given URI.
111   *
112   * @return list of proxy settings
113   * 
114   * @throws IllegalArgumentException If uri is null
115   */
116  public abstract List<Proxy> select(URI uri);
117}