Here you can find the source of millisecondsBetween(Date dt1, Date dt2)
public static long millisecondsBetween(Date dt1, Date dt2)
//package com.java2s; import java.util.Date; public class Main { public static long millisecondsBetween(Date dt1, Date dt2) { if (dt1 == null || dt2 == null) return 0; return Math.abs(dt1.getTime() - dt2.getTime()); }//from ww w. j a va2 s. c o m }