java时间相减

/**
	 * 时间相减
	 */
	public static void dataAddSubtract() throws ParseException {
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		String s1 = "2015-5-20 19:54:36";
		String s2 = "2015-5-18 3:5:5";
		Date date1 = sdf.parse(s1);
		Date date2 = sdf.parse(s2);
		long millisecond = date1.getTime() - date2.getTime();//毫秒
		System.out.println(millisecond);
		long day = millisecond / (1000 * 60 * 60 * 24);
		long hour = (millisecond - day * 24 * 60 * 60 * 1000) / (1000 * 60 * 60);
		long miniute = (millisecond - day * 24 * 60 * 60 * 1000 - hour * 60 * 60 * 1000) / (1000 * 60);
		long second = (millisecond - day * 24 * 60 * 60 * 1000 - hour * 60 * 60 * 1000 - miniute * 60 * 1000) / 1000;
		System.out.println("两个日期相差" + day + "天," + hour + "小时," + miniute + "分钟," + second + "秒");
	}