//判斷證書是否已過期6個月，如果已過期6個月，則註銷證書，重新申請。
Date dateNotAfter = cert.getNotAfter();//結束時間
Calendar calNotAfter = Calendar.getInstance();//定義一個Calendar對象calNotAfter.setTime(dateNotAfter);
calNotAfter.add(Calendar.MONTH, 6);
Date date = new Date();
Calendar datenow = Calendar.getInstance();
datenow.setTime(date);
if (calNotAfter.before(datenow)){
}else{
}
public boolean before(Object when) {
return when instanceof Calendar
&& compareTo((Calendar)when) < 0;
}
