我必须计算出发机场和到达机场之间的总飞行时间.
这项工作由以下代码片段完成:
- public int calculateFlightDuration(String departureDateTime,String depAirportCode,String arrivalDateTime,String arrAirportCode) {
- try {
- LocalDateTime depLocalTime = LocalDateTime.parse(departureDateTime,formatter);
- LocalDateTime arrLocalTime = LocalDateTime.parse(arrivalDateTime,formatter);
- ZoneOffset depZoneOffset = getTimeZoneOffset(depAirportCode);
- ZoneOffset arrZoneOffset = getTimeZoneOffset(arrAirportCode);
- if (depZoneOffset != null && arrZoneOffset != null) {
- OffsetDateTime offsetDepTime = OffsetDateTime.of(depLocalTime,depZoneOffset);
- OffsetDateTime offsetArrTime = OffsetDateTime.of(arrLocalTime,arrZoneOffset);
- Duration flightDuration = Duration.between(offsetArrTime,offsetDepTime).abs();
- return (int) flightDuration.toMinutes();
- }
- } catch (Exception e) {
- LOG.warn("::calculateFlightDuration depTime:{} dep.code:{} arrTime:{} arr.code:{}",departureDateTime,depAirportCode,arrivalDateTime,arrAirportCode);
- }
- return 0;
- }
这是问题所在:
当我想用这些参数计算未来航班的持续时间时:
- depLocalTime = 2017-11-06T14:50
- arrLocalTime = 2017-11-06T16:45
- depZoneOffset = +03:00
- arrZoneOffset = +02:00
作为这些参数的结果,flightDuration对象是:
- flightDuration = PT2H55M
似乎一切都好,对吧?但实际上并不好.让我解释;
出发机场代码是IST(土耳其),抵达机场代码是AMS(荷兰),这里是关键:
2017-10-29之后(在我计算的时间之前),AMS时间将支持1小时,其偏移量将为01:00,IST偏移量仍为03:00.所以正确的持续时间对象必须是:
- flightDuration = PT3H55M
我该如何解决这个问题?这真烦人.
谢谢你的帮助.
在ZonedDateTime评论后编辑:
伙计们,我也尝试过使用ZonedDateTime对象进行计算.这是使用ZonedDateTime对象的代码,它对结果没有影响.
- public int calculateFlightDuration(String departureDateTime,formatter);
- ZoneOffset depZoneOffset = getTimeZoneOffset(depAirportCode);
- ZoneOffset arrZoneOffset = getTimeZoneOffset(arrAirportCode);
- if (depZoneOffset != null && arrZoneOffset != null) {
- ZonedDateTime zonedDepTime = ZonedDateTime.of(depLocalTime,depZoneOffset);
- ZonedDateTime zonedArrTime = ZonedDateTime.of(arrLocalTime,arrZoneOffset);
- // OffsetDateTime offsetDepTime = OffsetDateTime.of(depLocalTime,depZoneOffset);
- // OffsetDateTime offsetArrTime = OffsetDateTime.of(arrLocalTime,arrZoneOffset);
- Duration flightDuration = Duration.between(zonedDepTime,zonedArrTime).abs();
- return (int) flightDuration.toMinutes();
- }
- } catch (Exception e) {
- LOG.warn("::calculateFlightDuration depTime:{} dep.code:{} arrTime:{} arr.code:{}",arrAirportCode);
- }
- return 0;
- }
在@Joe C的回答之后,我再次更改了代码,我相信这是我应该去的方式:
- public int calculateFlightDuration(String departureDateTime,formatter);
- ZoneId depZoneId = getTimeZoneId(depAirportCode);
- ZoneId arrZoneId = getTimeZoneId(arrAirportCode);
- if (depZoneId != null && arrZoneId != null) {
- ZonedDateTime zonedDepTime = ZonedDateTime.of(depLocalTime,depZoneId);
- ZonedDateTime zonedArrTime = ZonedDateTime.of(arrLocalTime,arrZoneId);
- Duration flightDuration = Duration.between(zonedDepTime,arrAirportCode);
- }
- return 0;
- }
但是:Java假设伊斯坦布尔也将其时区偏移量改为02:00,但不会发生.我想我还需要更新我的Java.以下是代码更改后的结果:
- depZoneId = Europe/Istanbul
- arrZoneId = Europe/Amsterdam
- zonedDepTime = 2017-11-06T14:50+02:00[Europe/Istanbul] //damn it's really annoying!
- zonedArrTime = 2017-11-06T16:45+01:00[Europe/Amsterdam]
aaand的飞行持续时间保持不变:
- flightDuration = PT2H55M
谢谢你的回答.现在我必须修复伊斯坦布尔的时区变化.
解决方法
OffsetDateTime
假定全年共同的偏移(例如UTC 2).它没有涵盖夏令时的任何内容.
如果您想考虑夏令时,则应使用ZonedDateTime
而不是ZoneId
.在Europe/Amsterdam
的情况下,它将根据一年中的时间选择UTC 1或UTC 2.
- ZonedDateTime zonedDepTime = ZonedDateTime.of(depLocalTime,ZoneId.of("Asia/Istanbul"));
- ZonedDateTime zonedArrTime = ZonedDateTime.of(arrLocalTime,ZoneId.of("Europe/Amsterdam"));