libjava/classpath/gnu/CORBA/SocketRepository.java

   1 /* SocketRepository.java --
   2    Copyright (C) 2005 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package gnu.CORBA;
  40
  41 import java.net.Socket;
  42 import java.net.SocketException;
  43 import java.util.HashMap;
  44 import java.util.Iterator;
  45 import java.util.Map;
  46
  47 /**
  48  * This class caches the opened sockets that are reused during the
  49  * frequent calls. Otherwise, some CORBA applications may spend
  50  * up to 90 % of the working time just for closing and opening the sockets.
  51  *
  52  * @author Audrius Meskauskas, Lithuania (AudriusA@Bioinformatics.org)
  53  */
  54 public class SocketRepository
  55 {
  56   /**
  57    * The socket map.
  58    */
  59   private static HashMap sockets = new HashMap();
  60
  61   /**
  62    * Put a socket. This method also discards all not reusable sockets from
  63    * the map.
  64    *
  65    * @param key as socket key.
  66    *
  67    * @param s a socket.
  68    */
  69   public static void put_socket(Object key, Socket s)
  70   {
  71     synchronized (sockets)
  72       {
  73         sockets.put(key, s);
  74         gc();
  75       }
  76   }
  77
  78   /**
  79    * Removes all non reusable sockets. As it is private,
  80    * we know we call from the synchronized code already.
  81    */
  82   private static void gc()
  83   {
  84     Iterator iter = sockets.entrySet().iterator();
  85
  86     Map.Entry e;
  87     Socket sx;
  88
  89     while (iter.hasNext())
  90       {
  91         e = (Map.Entry) iter.next();
  92         sx = (Socket) e.getValue();
  93
  94         if (not_reusable(sx))
  95           iter.remove();
  96       }
  97   }
  98
  99   /**
 100    * Return true if the socket is no longer reusable.
 101    */
 102   static boolean not_reusable(Socket s)
 103   {
 104     return (s.isClosed() || !s.isBound() || !s.isConnected() ||
 105         s.isInputShutdown() || s.isOutputShutdown());
 106   }
 107
 108   /**
 109    * Get a socket.
 110    *
 111    * @param key a socket key.
 112    *
 113    * @return an opened socket for reuse, null if no such available or it is
 114    * closed, its input or output has been shutown or otherwise the socket is not
 115    * reuseable.
 116    */
 117   public static Socket get_socket(Object key)
 118   {
 119     synchronized (sockets)
 120       {
 121         Socket s = (Socket) sockets.get(key);
 122         if (s == null)
 123           return null;
 124
 125         // Ensure that the socket is fully reusable.
 126         else if (not_reusable(s))
 127           {
 128             sockets.remove(key);
 129             return null;
 130           }
 131         else
 132           {
 133             try
 134               {
 135                 // Set one minute time out that will be changed later.
 136                 s.setSoTimeout(60 * 1000);
 137               }
 138             catch (SocketException e)
 139               {
 140                 s = null;
 141               }
 142
 143             sockets.remove(key);
 144             return s;
 145           }
 146       }
 147   }
 148 }