Program: 156089
Project: 156089
Buggy source:
@Override protected Object decode(Channel channel,SocketAddress remoteAddress,Object msg) throws Exception {
  String sentence=(String)msg;
  if (sentence.contains("String_Node_Str")) {
    if (channel != null) {
      channel.write("String_Node_Str",remoteAddress);
      Parser handshakeParser=new Parser(PATTERN_HANDSHAKE,sentence);
      if (handshakeParser.matches()) {
        identify(handshakeParser.next(),channel);
      }
    }
    return null;
  }
  if (sentence.length() == 15 && Character.isDigit(sentence.charAt(0))) {
    if (channel != null) {
      channel.write("String_Node_Str",remoteAddress);
    }
    return null;
  }
  Parser parser=new Parser(PATTERN,sentence);
  if (!parser.matches()) {
    return null;
  }
  Position position=new Position();
  position.setProtocol(getProtocolName());
  String imei=parser.next();
  if (!identify(imei,channel,remoteAddress)) {
    return null;
  }
  position.setDeviceId(getDeviceId());
  String alarm=parser.next();
  position.set(Event.KEY_ALARM,alarm);
  if (channel != null && alarm.equals("String_Node_Str")) {
    channel.write("String_Node_Str" + imei + "String_Node_Str",remoteAddress);
  }
  DateBuilder dateBuilder=new DateBuilder().setDate(parser.nextInt(),parser.nextInt(),parser.nextInt());
  int localHours=parser.nextInt();
  int localMinutes=parser.nextInt();
  String utcHours=parser.next();
  String utcMinutes=parser.next();
  dateBuilder.setTime(localHours,localMinutes,parser.nextInt(),parser.nextInt());
  if (utcHours != null && utcMinutes != null) {
    int deltaMinutes=(localHours - Integer.valueOf(utcHours)) * 60;
    deltaMinutes+=localMinutes - Integer.valueOf(utcMinutes);
    if (deltaMinutes <= -12 * 60) {
      deltaMinutes+=24 * 60;
    }
 else     if (deltaMinutes > 12 * 60) {
      deltaMinutes-=24 * 60;
    }
    dateBuilder.addMinute(-deltaMinutes);
  }
  position.setTime(dateBuilder.getDate());
  position.setValid(parser.next().equals("String_Node_Str"));
  position.setLatitude(parser.nextCoordinate(Parser.CoordinateFormat.HEM_DEG_MIN_HEM));
  position.setLongitude(parser.nextCoordinate(Parser.CoordinateFormat.HEM_DEG_MIN_HEM));
  position.setSpeed(parser.nextDouble());
  position.setCourse(parser.nextDouble());
  position.setAltitude(parser.nextDouble());
  for (int i=1; i <= 5; i++) {
    position.set(Event.PREFIX_IO + i,parser.next());
  }
  return position;
}

Fixed version (ground truth):
@Override protected Object decode(Channel channel,SocketAddress remoteAddress,Object msg) throws Exception {
  String sentence=(String)msg;
  if (sentence.contains("String_Node_Str")) {
    if (channel != null) {
      channel.write("String_Node_Str",remoteAddress);
      Parser handshakeParser=new Parser(PATTERN_HANDSHAKE,sentence);
      if (handshakeParser.matches()) {
        identify(handshakeParser.next(),channel);
      }
    }
    return null;
  }
  if (sentence.length() == 15 && Character.isDigit(sentence.charAt(0))) {
    if (channel != null) {
      channel.write("String_Node_Str",remoteAddress);
    }
    return null;
  }
  Parser parser=new Parser(PATTERN,sentence);
  if (!parser.matches()) {
    return null;
  }
  Position position=new Position();
  position.setProtocol(getProtocolName());
  String imei=parser.next();
  if (!identify(imei,channel,remoteAddress)) {
    return null;
  }
  position.setDeviceId(getDeviceId());
  String alarm=parser.next();
  position.set(Event.KEY_ALARM,alarm);
  if (channel != null && alarm.equals("String_Node_Str")) {
    channel.write("String_Node_Str" + imei + "String_Node_Str",remoteAddress);
  }
  DateBuilder dateBuilder=new DateBuilder().setDate(parser.nextInt(),parser.nextInt(),parser.nextInt());
  int localHours=parser.nextInt();
  int localMinutes=parser.nextInt();
  String utcHours=parser.next();
  String utcMinutes=parser.next();
  dateBuilder.setTime(localHours,localMinutes,parser.nextInt(),parser.nextInt());
  if (utcHours != null && utcMinutes != null) {
    int deltaMinutes=(localHours - Integer.parseInt(utcHours)) * 60;
    deltaMinutes+=localMinutes - Integer.parseInt(utcMinutes);
    if (deltaMinutes <= -12 * 60) {
      deltaMinutes+=24 * 60;
    }
 else     if (deltaMinutes > 12 * 60) {
      deltaMinutes-=24 * 60;
    }
    dateBuilder.addMinute(-deltaMinutes);
  }
  position.setTime(dateBuilder.getDate());
  position.setValid(parser.next().equals("String_Node_Str"));
  position.setLatitude(parser.nextCoordinate(Parser.CoordinateFormat.HEM_DEG_MIN_HEM));
  position.setLongitude(parser.nextCoordinate(Parser.CoordinateFormat.HEM_DEG_MIN_HEM));
  position.setSpeed(parser.nextDouble());
  position.setCourse(parser.nextDouble());
  position.setAltitude(parser.nextDouble());
  for (int i=1; i <= 5; i++) {
    position.set(Event.PREFIX_IO + i,parser.next());
  }
  return position;
}