protected boolean loadFieldNameFilterConverter(Directory directory, String geoFileName,
IFieldNameFilterConverter fieldNameFilterConverter) throws IOException {
try {
DataInput input = directory.openInput(geoFileName);
input.readVInt(); //read version
input.readInt(); //throw out tree position
input.readVInt(); //throw out tree size
input.readVInt(); //throw out record length
fieldNameFilterConverter.loadFromInput(input);