从 SimpleTimeZone 获取 ZoneId

2022-01-16 00:00:00 timezone dst java java-time

使用 Java，我有一个 SimpleTimeZone 实例，其中包含来自旧系统的 GMT 偏移和夏令时信息.

Using Java I have a SimpleTimeZone instance with GMT offset and daylight saving time information from a legacy system.

我想检索 ZoneId 以便能够使用 Java 8 时间 API.

I would like to retrieve ZoneId to be able to use Java 8 time API.

实际上，toZoneId 返回一个没有夏令时信息的 ZoneId

Actually, toZoneId returns a ZoneId without the daylight Saving time infos

SimpleTimeZone stz = new SimpleTimeZone( 2 * 60 * 60 * 1000, "GMT", Calendar.JANUARY,1,1,1, Calendar.FEBRUARY,1,1,1, 1 * 60 * 60 * 1000);
stz.toZoneId();

推荐答案

这里的解决方案我比较喜欢，因为它很简单，但是你需要一个 Date 和一个 TimeZone 作为参数来检索 ZoneId

Here the solution i prefer because it's simple, but you need a Date and a TimeZone as parameters to retrievethe the ZoneId

private ZoneId getZoneOffsetFor(final Date date, final TimeZone timeZone){
  int offsetInMillis = getOffsetInMillis(date, timeZone);
  return ZoneOffset.ofTotalSeconds( offsetInMillis / 1000 );
}

private int getOffsetInMillis(final Date date, final TimeZone timeZone){
  int offsetInMillis = timeZone.getRawOffset();
  if(timeZone.inDaylightTime(date)){
     offsetInMillis += timeZone.getDSTSavings();
  }
  return offsetInMillis;
}

相关文章