Date now = new Date(); Calendar cal1 = Calendar.getInstance(); cal1.setTime(now); // 将时分秒,毫秒域清零 cal1.set(Calendar.HOUR_OF_DAY, 0); cal1.set(Calendar.MINUTE, 0); cal1.set(Calendar.SECOND, 0); cal1.set(Calendar.MILLISECOND, 0); System.out.printf("%1$tF %1$tT\n", cal1.getTime());// cal1.getTime()返回的Date已经是更新后的对象