Sort of a collection of the relevant date

With Collections tools to achieve sorted by date

1, the date of collection of the sort

2, comprising a set of fields like the date field is sorted by date

public static void main(String[] args) throws ParseException {
   SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
   String a = "2019-08-01 08:00:00";
   String b = "2019-08-01 18:00:00";
   String c = "2019-08-01 15:00:00";
   Date d1 = sdf.parse(a);
   Date d2 = sdf.parse(b);
   Date d3 = sdf.parse(c);
   List<Date> list = new ArrayList<>();
   list.add(d1);
   list.add(d2);
   list.add(d3);
   Collections.sort(list, new Comparator<Date>() {
      @Override
      public int compare(Date o1, Date o2) {
         return o1.compareTo(o2);
      }
   });
   System.out.println(list);
}
Outputs the print result: 
[ 
Thu 01-Aug 2019 08:00:00 CST, 
Thu 01-Aug 2019 15:00:00 CST, 
Thu-Aug 01 18:00:00 CST 2019 
] 

If the class (e.g. CheckInformation for a date property field for the private Date checkTime), can be rewritten as:

Collections.sort(list,Comparator.comparing(CheckInformation::getCheckTime));