Here you can find the source of secondsBetween(Date dt1, Date dt2)
public static int secondsBetween(Date dt1, Date dt2)
//package com.java2s; //License from project: Open Source License import java.util.Date; public class Main { public static int secondsBetween(Date dt1, Date dt2) { long msDiff = millisecondsBetween(dt1, dt2); if (msDiff == 0) { return 0; }/*from www .j av a 2s .c om*/ return (int) (msDiff / 1000); } public static long millisecondsBetween(Date dt1, Date dt2) { if (dt1 == null || dt2 == null) return 0; return Math.abs(dt1.getTime() - dt2.getTime()); } }