Set<Unit> allInactiveSubUnits = new HashSet<Unit>();
List<Unit> allInactiveSubUnits = new ArrayList<Unit>();
    public List<Unit> getInactiveSubUnits(Date currentDate) {                Set<Unit> allInactiveSubUnits = new HashSet<Unit>();                for (Unit subUnit : this.getSubUnits()) {            readAndSaveInactiveSubUnits(subUnit, allInactiveSubUnits, currentDate);        }                        return new ArrayList<Unit>(allInactiveSubUnits);    }