code: /***************************************************************************
   *   Copyright (C) 2008-2009 by Fabrizio Montesi <famontesi@gmail.com>     *
   *                                                                         *
   *   This program is free software; you can redistribute it and/or modify  *
   *   it under the terms of the GNU Library General Public License as       *
   *   published by the Free Software Foundation; either version 2 of the    *
   *   License, or (at your option) any later version.                       *
   *                                                                         *
   *   This program is distributed in the hope that it will be useful,       *
   *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
   *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
   *   GNU General Public License for more details.                          *
   *                                                                         *
   *   You should have received a copy of the GNU Library General Public     *
   *   License along with this program; if not, write to the                 *
   *   Free Software Foundation, Inc.,                                       *
   *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
   *                                                                         *
   *   For details about the authors of this software, see the AUTHORS file. *
   ***************************************************************************/
  
  package jolie.net;
  
  import java.io.ByteArrayInputStream;
  import java.io.ByteArrayOutputStream;
  import java.io.IOException;
  import java.net.URI;
  import java.util.Arrays;
  import javax.bluetooth.L2CAPConnection;
  import jolie.Interpreter;
  import jolie.net.protocols.CommProtocol;
  
  public class BTL2CapCommChannel extends StreamingCommChannel implements PollableCommChannel
  {
  	private final L2CAPConnection connection;
  	private final int sendMTU;
  	private final int recvMTU;
  	
  	public BTL2CapCommChannel( L2CAPConnection connection, URI location, CommProtocol protocol )
  		throws IOException
  	{
  		super( location, protocol );
  		this.connection = connection;
  		sendMTU = connection.getTransmitMTU();
  		recvMTU = connection.getReceiveMTU();
  		setToBeClosed( false ); // Bluetooth connections are kept open by default.
  	}
  	
  	protected void sendImpl( CommMessage message )
  		throws IOException
  	{
  		ByteArrayOutputStream ostream = new ByteArrayOutputStream();
  		protocol().send( ostream, message, null ); // TODO Fix this null pointer.
  		byte[] result = ostream.toByteArray();
  		if ( result.length > sendMTU ) {
  			int times = (result.length / sendMTU);
  			byte[] chunk;
  			int i;
  			for( i = 0; i < times; i++ ) {
  				chunk = Arrays.copyOfRange( result, i*sendMTU, ((i+1)*sendMTU) );
  				connection.send( chunk );
  			}
  			int remaining = result.length % sendMTU;
  			if ( remaining > 0 ) {
  				chunk = Arrays.copyOfRange( result, i*sendMTU, (i*sendMTU) + remaining );
  				connection.send( chunk );
  			}
  		} else {
  			connection.send( result );
  		}
  	}
  
  	protected CommMessage recvImpl()
  		throws IOException
  	{
  		ByteArrayOutputStream ostream = new ByteArrayOutputStream();
  		byte[] chunk;
  		int len = recvMTU;
  		while( len >= recvMTU ) {
  			chunk = new byte[ recvMTU ]; // Most probably we do not need to re-initialize this
  			len = connection.receive( chunk );
  			ostream.write( chunk, 0, len );
  		}
  		ByteArrayInputStream istream = new ByteArrayInputStream( ostream.toByteArray() );
  		return protocol().recv( istream, null ); // TODO fix this null pointer
  	}
  	
  	protected void closeImpl()
  		throws IOException
  	{
  		connection.close();
  	}
  	
  	@Override
  	protected void disposeForInputImpl()
  		throws IOException
  	{
  		Interpreter.getInstance().commCore().registerForPolling( this );
  	}
  	
  	public boolean isReady()
  	{
  		try {
  			return connection.ready();
  		} catch( IOException e ) {
  			return false;
  		}
  	}
  }
  