Date日期比对

　　　　 Calendar calendar1 = Calendar.getInstance();
        Calendar calendar2 = Calendar.getInstance();
        calendar1.set(2007, 01, 10);
        calendar2.set(2008, 07, 01);
        long milliseconds1 = calendar1.getTimeInMillis();
        long milliseconds2 = calendar2.getTimeInMillis();
        long diff = milliseconds2 - milliseconds1;
        long diffSeconds = diff / 1000;
        long diffMinutes = diff / (60 * 1000);
        long diffHours = diff / (60 * 60 * 1000);
        long diffDays = diff / (24 * 60 * 60 * 1000);
        System.out.println("
The Date Different Example");
        System.out.println("Time in milliseconds: " + diff + " milliseconds.");
        System.out.println("Time in 秒: " + diffSeconds + " seconds.");
        System.out.println("Time in 分钟: " + diffMinutes + " minutes.");
        System.out.println("Time in 小时: " + diffHours + " hours.");
        System.out.println("Time in 天: " + diffDays + " days.");