How to find the duration of difference between two dates in java?

Question

I have two objects of DateTime, which need to find the duration of their difference,

I have the following code but not sure how to continue it to get to the expected results as following:

Example:

      11/03/14 09:30:58
      11/03/14 09:33:43
      elapsed time is 02 minutes and 45 seconds
      -----------------------------------------------------
      11/03/14 09:30:58 
      11/03/15 09:30:58
      elapsed time is a day
      -----------------------------------------------------
      11/03/14 09:30:58 
      11/03/16 09:30:58
      elapsed time is two days
      -----------------------------------------------------
      11/03/14 09:30:58 
      11/03/16 09:35:58
      elapsed time is two days and 05 minutes
      

Code:

    String dateStart = "11/03/14 09:29:58";
    String dateStop = "11/03/14 09:33:43";

    Custom date format
    SimpleDateFormat format = new SimpleDateFormat("yy/MM/dd HH:mm:ss");

    Date d1 = null;
    Date d2 = null;
    try {
        d1 = format.parse(dateStart);
        d2 = format.parse(dateStop);
    } catch (ParseException e) {
        e.printStackTrace();
    }

    // Get msec from each, and subtract.
    long diff = d2.getTime() - d1.getTime();
    long diffSeconds = diff / 1000 % 60;
    long diffMinutes = diff / (60 * 1000) % 60;
    long diffHours = diff / (60 * 60 * 1000);
    System.out.println("Time in seconds: " + diffSeconds + " seconds.");
    System.out.println("Time in minutes: " + diffMinutes + " minutes.");
    System.out.println("Time in hours: " + diffHours + " hours.");

Answer 1

The date difference conversion could be handled in a better way using Java built-in class, TimeUnit. It provides utility methods to do that:

Date startDate = // Set start date
Date endDate   = // Set end date

long duration  = endDate.getTime() - startDate.getTime();

long diffInSeconds = TimeUnit.MILLISECONDS.toSeconds(duration);
long diffInMinutes = TimeUnit.MILLISECONDS.toMinutes(duration);
long diffInHours = TimeUnit.MILLISECONDS.toHours(duration);
long diffInDays = TimeUnit.MILLISECONDS.toDays(duration);