code: public static long getSecondsDifference(Date startDate, Date endDate) {
  		long startTime = startDate.getTime();
  		long endTime = endDate.getTime();
  		long diffTime = endTime - startTime;
  		long diffInSeconds = TimeUnit.MILLISECONDS.toSeconds(diffTime);
  		return diffInSeconds;
  	}
docs: Gets the seconds difference.
  
  @param startDate the start date
  @param endDate   the end date
  @return the seconds difference