Java tutorial
//package com.java2s; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; public class Main { public static int getDiffHour(String startTime, String endTime) { long diff = 0; SimpleDateFormat ft = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); try { Date startDate = ft.parse(startTime); Date endDate = ft.parse(endTime); diff = startDate.getTime() - endDate.getTime(); diff = diff / (1000 * 60 * 60); } catch (ParseException e) { e.printStackTrace(); } return new Long(diff).intValue(); } }