小弟刚接触drools,在LHS中,使用到日期来做条件,请问日期应该如何比较?请大家指点指点!!

when
$c:Calendar($time:time)
$ol:OrderList(softwareId==1)
$p:Promotion(beginDate > endDate)
then
System.out.println("=====i=time = " + $time);