1  /*
     2   * Copyright (c) 2006-2009 Chris Smith, Shane Mc Cormack, Gregory Holmes
     3   *
     4   * Permission is hereby granted, free of charge, to any person obtaining a copy
     5   * of this software and associated documentation files (the "Software"), to deal
     6   * in the Software without restriction, including without limitation the rights
     7   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     8   * copies of the Software, and to permit persons to whom the Software is
     9   * furnished to do so, subject to the following conditions:
    10   *
    11   * The above copyright notice and this permission notice shall be included in
    12   * all copies or substantial portions of the Software.
    13   *
    14   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    15   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    16   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    17   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    18   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    19   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
    20   * SOFTWARE.
    21   */
    22  
    23  package com.dmdirc.commandline;
    24  
    25  import com.dmdirc.logger.ErrorLevel;
    26  import com.dmdirc.logger.Logger;
    27  import com.dmdirc.util.IrcAddress;
    28  
    29  import java.rmi.NotBoundException;
    30  import java.rmi.RemoteException;
    31  import java.rmi.registry.LocateRegistry;
    32  import java.rmi.registry.Registry;
    33  import java.rmi.server.UnicastRemoteObject;
    34  import java.util.List;
    35  
    36  /**
    37   * An RMI server that allows other clients to interact with DMDirc.
    38   * 
    39   * @author chris
    40   */
    41  public class RemoteServer implements RemoteInterface {
    42      
    43      /** The minimum port to use for RMI binding. */
    44      private static final int MINPORT = 3634;
    45      /** The maximum port to use for RMI binding. */
    46      private static final int MAXPORT = MINPORT + 5;
    47      /** The interface we're exposing. */
             /* 
    P/P       *  Method: com.dmdirc.commandline.RemoteServer__static_init
              * 
              *  Postconditions:
              *    SERVER == &new RemoteServer(RemoteServer__static_init#1)
              *    new RemoteServer(RemoteServer__static_init#1) num objects == 1
              */
    48      private static final RemoteServer SERVER = new RemoteServer();
    49      
    50      /**
    51       * Creates a new instance of RemoteServer.
    52       */
    53      public RemoteServer() {
                 /* 
    P/P           *  Method: void com.dmdirc.commandline.RemoteServer()
                  */
    54          super();
    55      }
    56      
    57      /** {@inheritDoc} */
    58      @Override
    59      public void connect(final List<IrcAddress> addresses) throws RemoteException {
                 /* 
    P/P           *  Method: void connect(List)
                  * 
                  *  Preconditions:
                  *    addresses != null
                  * 
                  *  Presumptions:
                  *    java.util.Iterator:next(...)@60 != null
                  * 
                  *  Test Vectors:
                  *    java.util.Iterator:hasNext(...)@60: {0}, {1}
                  */
    60          for (IrcAddress address : addresses) {
    61              address.connect();
    62          }
    63      }    
    64      
    65      /**
    66       * Binds to the RMI registry so that other clients may find this remote
    67       * server.
    68       */
    69      public static void bind() {
    70          RemoteInterface stub;
    71          
    72          try {
                     /* 
    P/P               *  Method: void bind()
                      * 
                      *  Presumptions:
                      *    init'ed(com.dmdirc.logger.ErrorLevel.MEDIUM)
                      *    java.rmi.registry.LocateRegistry:createRegistry(...)@81 != null
                      */
    73              stub = (RemoteInterface) UnicastRemoteObject.exportObject(SERVER, 0);
    74          } catch (RemoteException ex) {
    75              Logger.appError(ErrorLevel.MEDIUM, "Unable to export remote interface", ex);
    76              return;
    77          }
    78          
    79          for (int port = MINPORT; port < MAXPORT; port++) {
    80              try {
    81                  final Registry registry = LocateRegistry.createRegistry(port);
    82                  registry.rebind("DMDirc", stub);
    83                  return;
    84              } catch (RemoteException ex) {
    85                  continue;
    86              }
    87          }
    88      }
    89      
    90      /**
    91       * Retrieves a reference to an existing RemoteServer, if there is one.
    92       * Note that this must be called before bind(), unless you want a reference
    93       * to our own client for some reason.
    94       * 
    95       * @return The RemoteServer instance, or null if none was available
    96       */
    97      public static RemoteInterface getServer() {
                 /* 
    P/P           *  Method: RemoteInterface getServer()
                  * 
                  *  Presumptions:
                  *    java.rmi.registry.LocateRegistry:getRegistry(...)@100 != null
                  * 
                  *  Postconditions:
                  *    init'ed(return_value)
                  */
    98          for (int port = MINPORT; port < MAXPORT; port++) {
    99              try {
   100                  final Registry registry = LocateRegistry.getRegistry("localhost", port);
   101                  final RemoteInterface iface = (RemoteInterface) registry.lookup("DMDirc");
   102                  
   103                  if (iface == null) {
   104                      continue;
   105                  } else {
   106                      return iface;
   107                  }
   108              } catch (RemoteException ex) {
   109                  continue;
   110              } catch (NotBoundException ex) {
   111                  continue;
   112              }
   113          }
   114          
   115          // No RMI server found
   116          return null;
   117      }
   118  
   119  }