private void mapGtfsToFdotSchema(){		
		mapping = new HashMap<String, Integer>();
		List<String> fdotFields = fdSchema.getFields();
		
		if(_entity.contains("stops")){
			fdotFields.remove("stop_pos");
			fdotFields.add("stop_pos");
		}
		
		ArrayList<String> gtfsFieldsUnmapped = new ArrayList<String>();
		
		HashMap<String, String> specialMapping = getSpecialMapping();
		
		for(int i=0; i<_fields.size(); i++){
			String gtfsField = _fields.get(i);
			boolean isMapped = false;
			
			if(specialMapping.keySet().contains(gtfsField))
				gtfsField = specialMapping.get(gtfsField);
			
			for(int j=0; j<fdotFields.size(); j++){
				if(gtfsField.equals(fdotFields.get(j))){
					mapping.put(_fields.get(i), j);
					isMapped = true;
					break;
				}
			}
			if(!isMapped) 
				gtfsFieldsUnmapped.add(gtfsField);
		}
	}