/*    This file is part of Peers.    This program is free software: you can redistribute it and/or modify    it under the terms of the GNU General Public License as published by    the Free Software Foundation, either version 3 of the License, or    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 General Public License    along with this program.  If not, see <http://www.gnu.org/licenses/>.        Copyright 2007, 2008 Yohann Martineau */package net.sourceforge.peers.sip.transport;import java.io.ByteArrayInputStream;import java.io.IOException;import java.io.UnsupportedEncodingException;import java.net.InetAddress;import net.sourceforge.peers.Logger;import net.sourceforge.peers.sip.RFC3261;import net.sourceforge.peers.sip.Utils;import net.sourceforge.peers.sip.core.useragent.UAS;import net.sourceforge.peers.sip.syntaxencoding.SipHeaderFieldValue;import net.sourceforge.peers.sip.syntaxencoding.SipHeaderParamName;import net.sourceforge.peers.sip.syntaxencoding.SipParserException;import net.sourceforge.peers.sip.transaction.ClientTransaction;import net.sourceforge.peers.sip.transaction.ServerTransaction;import net.sourceforge.peers.sip.transaction.TransactionManager;public abstract class MessageReceiver implements Runnable {    public static final int BUFFER_SIZE = 2048;//FIXME should correspond to MTU 1024;    public static final String CHARACTER_ENCODING = "US-ASCII";        protected int port;    private boolean isListening;    public MessageReceiver(int port) {        super();        this.port = port;        isListening = true;    }        public void run() {        while (isListening) {            try {                listen();            } catch (IOException e) {                e.printStackTrace();            }        }    }    protected abstract void listen() throws IOException;        protected boolean isRequest(byte[] message) {        String beginning = null;        try {            beginning = new String(message, 0,                    RFC3261.DEFAULT_SIP_VERSION.length(), CHARACTER_ENCODING);        } catch (UnsupportedEncodingException e) {            e.printStackTrace();        }        if (RFC3261.DEFAULT_SIP_VERSION.equals(beginning)) {            return false;        }        return true;    }        protected void processMessage(byte[] message, InetAddress sourceIp)            throws IOException {        SipMessage sipMessage = null;        try {            sipMessage = TransportManager.getInstance().sipParser                    .parse(new ByteArrayInputStream(message));        } catch (IOException e) {            e.printStackTrace();        } catch (SipParserException e) {            e.printStackTrace();        }        if (sipMessage == null) {            return;        }        TransactionManager transactionManager = TransactionManager.getInstance();        if (sipMessage instanceof SipRequest) {            SipRequest sipRequest = (SipRequest)sipMessage;                                    SipHeaderFieldValue topVia = Utils.getInstance().getTopVia(sipRequest);            String sentBy =                topVia.getParam(new SipHeaderParamName(RFC3261.PARAM_SENTBY));            if (sentBy != null) {                int colonPos = sentBy.indexOf(RFC3261.TRANSPORT_PORT_SEP);                if (colonPos < 0) {                    colonPos = sentBy.length();                }                sentBy = sentBy.substring(0, colonPos);            }            if (InetAddress.getByName(sentBy).equals(sourceIp)) {                topVia.addParam(new SipHeaderParamName(RFC3261.PARAM_RECEIVED),                        sourceIp.getHostAddress());            }                                                ServerTransaction serverTransaction =                transactionManager.getServerTransaction(sipRequest);            if (serverTransaction == null) {                UAS.getInstance().messageReceived(sipMessage);            } else {                serverTransaction.receivedRequest(sipRequest);            }        } else {            SipResponse sipResponse = (SipResponse)sipMessage;            ClientTransaction clientTransaction =                transactionManager.getClientTransaction(sipResponse);            Logger.getInstance().debug("ClientTransaction = " + clientTransaction);            if (clientTransaction == null) {                UAS.getInstance().messageReceived(sipMessage);            } else {                clientTransaction.receivedResponse(sipResponse);            }        }    }        public synchronized void setListening(boolean isListening) {        this.isListening = isListening;    }    public synchronized boolean isListening() {        return isListening;    }    }