presto-hive/src/main/java/io/prestosql/plugin/hive/metastore/thrift/ThriftMetastoreUtil.java/ThriftMetastoreUtil/fromMetastoreNullsCount
class ThriftMetastoreUtil:    private static OptionalLong fromMetastoreNullsCount(long nullsCount)
    {
        if (nullsCount == -1L) {
            return OptionalLong.empty();
        }
        return OptionalLong.of(nullsCount);
    }