如何找到从Java午夜开始经过的秒数？

如果您使用的是Java> = 8，这很容易做到：

ZonedDateTime nowZoned = ZonedDateTime.now();Instant midnight = nowZoned.toLocalDate().atStartOfDay(nowZoned.getZone()).toInstant();Duration duration = Duration.between(midnight, Instant.now());long seconds = duration.getSeconds();

如果您使用的是Java 7或更低版​​本，则必须通过Calendar从午夜开始获取日期，然后减去。

Calendar c = Calendar.getInstance();long now = c.getTimeInMillis();c.set(Calendar.HOUR_OF_DAY, 0);c.set(Calendar.MINUTE, 0);c.set(Calendar.SECOND, 0);c.set(Calendar.MILLISECOND, 0);long passed = now - c.getTimeInMillis();long secondsPassed = passed / 1000;