campus.iterator().next();
return campus.iterator().next();
    public Campus getCurrentCampus() {	final YearMonthDay now = new YearMonthDay();		final List<Campus> campus = getAssiduousness().getCampusForInterval(now, now);	if (campus.size() > 1) {	    throw new DomainException("Employee.with.more.than.one.campus.for.same.day");	} else if (!campus.isEmpty()) {	    campus.iterator().next();	}		return null;     }