private void registerExtraValidSubject(String subject){
  extraValidSubjects.add(subject);
  restoredStatements.addAll(unknownSubjects.removeAll(subject));
}

private void registerExtraValidSubject ( String subject ) { extraValidSubjects . add ( subject ) ; restoredStatements . addAll ( unknownSubjects . removeAll ( subject ) ) ; }
register an extra valid subject . these subjects are ok if we hit them .
