如何在Java中计算时差？

String time1 = "16:00:00";String time2 = "19:00:00";SimpleDateFormat format = new SimpleDateFormat("HH:mm:ss");Date date1 = format.parse(time1);Date date2 = format.parse(time2);long difference = date2.getTime() - date1.getTime(); 

差异以毫秒为单位。