org.mariadb.jdbc.internal.com.send.parameters.OffsetTimeParameter seems to be broken. It contains the following code:

    ZoneId zoneId = options.useLegacyDatetimeCode ? ZoneOffset.systemDefault() : 

serverZoneId;

    if (zoneId instanceof ZoneOffset) {

      throw new SQLException("cannot set OffsetTime, since server time zone is set to '"

          + serverZoneId.toString() + "' (check server variables time_zone and system_time_zone)");

    }

    this.time = offsetTime.withOffsetSameInstant((ZoneOffset) zoneId);

I am not sure how it is supposed to work but atm it does not seem to be possible to pass in any zoneId that would be accepted. First a validation makes sure that the zoneId is not ZoneOffset and granted that validation is passed, it is then immediately cast to ZoneOffset which fails. So - neither ZoneRegion nor ZoneOffset work here.

org.mariadb.jdbc.internal.com.send.parameters.ZonedDateTimeParameter does not seem to have the validation block, so maybe this is unnecessary also here?

When I implemented my own ParameterHolder and set it on the Statement using setParameter, it was possible to save Java 8 Time types to the DB