You can use custom period like e.g. 8 minutes bars.
Be aware that custom periods can be only integer multiplier of 24 hours (i.e. 1440 minutes)Sample:
Period m8 = Period.createCustomPeriod(Unit.Minute, 8, JFTimeZone.EET);
history.getBars(instrument, m8, OfferSide.BID, Filter.WEEKENDS, timeFrom, timeTo)
See debugger with list of 8 minutes bars: