bundles/org.simantics.databoard/src/org/simantics/databoard/method/Server.java

   1 /*******************************************************************************
   2  *  Copyright (c) 2010 Association for Decentralized Information Management in
   3  *  Industry THTH ry.
   4  *  All rights reserved. This program and the accompanying materials
   5  *  are made available under the terms of the Eclipse Public License v1.0
   6  *  which accompanies this distribution, and is available at
   7  *  http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  *  Contributors:
  10  *      VTT Technical Research Centre of Finland - initial API and implementation
  11  *******************************************************************************/
  12 package org.simantics.databoard.method;
  13
  14 import java.io.IOException;
  15 import java.net.ServerSocket;
  16 import java.net.Socket;
  17 import java.util.List;
  18 import java.util.concurrent.CopyOnWriteArrayList;
  19 import java.util.logging.Level;
  20 import java.util.logging.Logger;
  21
  22 import org.simantics.databoard.method.TcpConnection.ConnectionListener;
  23
  24 /**
  25  * Server opens a server socket and accepts incoming connections.
  26  * <p>
  27  * Methods are invoked in read thread. Therefore method invocation blocks
  28  * the whole socket.
  29  * It is highly recommended that that MethodInterface implementation is
  30  * non-blocking.
  31  *
  32  * @author Toni Kalajainen <toni.kalajainen@vtt.fi>
  33  */
  34 public class Server {
  35
  36         static Logger LOGGER = Logger.getLogger(Server.class.getName());
  37
  38         ServerSocket socket;
  39         Thread acceptThread;
  40         MethodInterface handler;
  41         List<TcpConnection> connections = new CopyOnWriteArrayList<TcpConnection>();
  42
  43         /**
  44          * Create new method interface server.
  45          *
  46          * @param port
  47          * @param handler method handler of local methods or
  48          * @throws IOException
  49          */
  50         public Server(int port, MethodInterface handler)
  51         throws IOException
  52         {
  53                 this.handler = handler;
  54
  55                 socket = new ServerSocket(port);
  56                 acceptThread = new Thread() {
  57                         @Override
  58                         public void run() {
  59                                 while(true) {
  60                                         Socket s;
  61                                         try {
  62                                                 s = socket.accept();
  63                                         } catch (IOException e) {
  64                                                 return;
  65                                         }
  66
  67                                         try {
  68                                                 Handshake local = new Handshake();
  69                                                 local.methods = Server.this.handler.getInterface().getMethodDefinitions();
  70                                                 Handshake remote = TcpConnection.handshake(s, local);
  71                                                 final TcpConnection c = new TcpConnection(s, Server.this.handler, local, remote);
  72                                                 c.addConnectionListener(new ConnectionListener() {
  73                                                         @Override
  74                                                         public void onClosed() {
  75                                                                 connections.remove(c);
  76                                                         }
  77                                                         @Override
  78                                                         public void onError(Exception error) {
  79                                                                 connections.remove(c);
  80                                                         }
  81                                                 });
  82
  83                                                 connections.add( c );
  84                                                 if (c.getSocket().isClosed()) connections.remove(c);
  85                                         } catch (IOException e) {
  86                                                 LOGGER.log(Level.FINER, "Connection Closed");
  87                                                 try {
  88                                                         s.close();
  89                                                 } catch (IOException e1) {
  90                                                 }
  91                                         }
  92                                 }
  93                         }
  94                 };
  95                 acceptThread.setDaemon(true);
  96                 acceptThread.start();
  97         }
  98
  99         /**
 100          * Stop listening for new connections and shutdown existing connections.
 101          */
 102         public void close() {
 103                 try {
 104                         socket.close();
 105                 } catch (IOException e) {
 106                 }
 107                 for (TcpConnection c : connections) {
 108                         c.close();
 109                         try {
 110                                 c.getSocket().close();
 111                         } catch (IOException e) {
 112                         }
 113                 }
 114         }
 115
 116         /**
 117          * @return The port the server is listening.
 118          */
 119         public int getPort() {
 120                 return socket.getLocalPort();
 121         }
 122
 123 }
 124