presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/RaptorTableProperties.java/RaptorTableProperties/getBucketCount
class RaptorTableProperties:    public static OptionalInt getBucketCount(Map<String, Object> tableProperties)
    {
        Integer value = (Integer) tableProperties.get(BUCKET_COUNT_PROPERTY);
        return (value != null) ? OptionalInt.of(value) : OptionalInt.empty();
    }