public void setPeriodBeforeEnd ( ReadablePeriod period ) { if ( period == null ) { setStartMillis ( getEndMillis ( ) ) ; } else { setStartMillis ( getChronology ( ) . add ( period , getEndMillis ( ) , - 1 ) ) ; } }
Sets the period of this time interval preserving the end instant and using the ISOChronology in the default zone for calculations .