public String printableUniqueKey(org.apache.lucene.document.Document doc){
  IndexableField f=doc.getField(uniqueKeyFieldName);
  return f == null ? null : uniqueKeyFieldType.toExternal(f);
}

public String printableUniqueKey ( org . apache . lucene . document . Document doc ) { IndexableField f = doc . getField ( uniqueKeyFieldName ) ; return f == null ? null : uniqueKeyFieldType . toExternal ( f ) ; }
the printable value of the unique key field for the specified document
