如何在Java中按日期/时间比较和排序列表？

Question

How do i implement a java comparator class which can sort the order of the list of date/time strings?

Like eg

i have

2012-06-15T12:01:00.000+08:00
2012-06-25T12:15:00.000+08:00
2012-06-08T00:00:00.000Z

Then it should be sorted like

2012-06-08T00:00:00.000Z
2012-06-15T12:01:00.000+08:00
2012-06-25T12:15:00.000+08:00

Answer 1

You have two issues here (since parsing the strings directly is not going to work).

1. Convert your strings into dates. See SimpleDateFormat for more info and the DateFormat.parse() method
2. Sort the subsequent dates in a collection using Collections.sort .

Answer 2

Parse them into java.util.Date . Date already implements Comparable

Answer 3

well, If you want a quick solution, it is as follows.

http://www.ltg.ed.ac.uk/NITE/nxt/apidoc/net/sourceforge/nite/util/SortedList.html .

Also, if you are confidant every date will be different, then do use TreeSet.You can use them as follows.

Make a new TreeSet and keep adding your dates in them. It will be automatically sorted, As TreeSet sorts all objects it contains, if they implement comparable.(or comparator provided).