question: private static void checkSharedVocabularyChecksumsForPackedGrammars ( final List < PackedGrammar > packed_grammars ) { String previous_checksum = "" ; for ( PackedGrammar grammar : packed_grammars ) { final String checksum = grammar . computeVocabularyChecksum ( ) ; if ( previous_checksum . isEmpty ( ) ) { previous_checksum = checksum ; } else { if ( ! checksum . equals ( previous_checksum ) ) { throw new RuntimeException ( "Trying to load multiple packed grammars with different vocabularies!" + "Have you packed them jointly?" ) ; } previous_checksum = checksum ; } } }
target:  Checks if multiple packedGrammars have the same vocabulary by comparing their vocabulary file checksums.