java - 日历 <= 另一个日历

Question

while (r.next()) {
    String rn = r.getString(3);
    String sqldate = r.getString(2); // database reservation date
}

从数据库获取日期

DateFormat RD = new SimpleDateFormat("yyyy-MM-dd");
     java.sql.Date converteddate = new java.sql.Date(RD.parse(sqldate).getTime());
     Calendar cal = Calendar.getInstance();
     Calendar cal1 = Calendar.getInstance();
     cal.setTime(converteddate);
     cal.add(Calendar.DATE, 7);
     if(cal<=cal1){ }// i need to this opration i dont know how

我需要检查 cal 是否 <= Cal1。有什么想法吗？

Answer 1

日历是可比较的，您可以使用 Calendar#compareTo() method :

compareTo returns the value 0 if the time represented by the argument is equal to the time represented by this Calendar; a value less than 0 if the time of this Calendar is before the time represented by the argument; and a value greater than 0 if the time of this Calendar is after the time represented by the argument

在您的情况下，要确定 cal 是否早于或等于 cal1，您可以使用:

if (cal.compareTo(cal1) <= 0) {}