presto-hive/src/main/java/io/prestosql/plugin/hive/util/SerDeUtils.java/SerDeUtils/formatTimestampAsLong
class SerDeUtils:    private static long formatTimestampAsLong(Object object, TimestampObjectInspector inspector)
    {
        Timestamp timestamp = getTimestamp(object, inspector);
        return timestamp.getTime();
    }