java Date型日期时间类型比较大小

java Date型时间类型比较大小compareTo String DateStr1 = "2011-10-1 10:20:16"; String DateStr2 = "2011-10-07 15:50:35"; DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); Date dateTime1 = dateFormat.parse(DateStr1); Date dateTime2 = dateFormat.parse(DateStr2);// i=-1时候 左边小于右边 int i = dateTime1.compareTo(dateTime2); System.out.println(i < 0); //输出truebefore/after// 判断左边比右边早 System.out.println(dateTime1.before(dateTime2));// 判断左边比右边晚 System.out.println(dateTime1.after(dateTime2));