Java SimpleDateFormat解析Timezone,如America/Los_Angeles

Question

我想在Java中解析以下字符串并将其转换为日期:

DTSTART;TZID=America/Los_Angeles:20140423T120000

我试过这个:

SimpleDateFormat sdf = new SimpleDateFormat("'DTSTART;TZID='Z':'yyyyMMdd'T'hhmmss");
Date start = sdf.parse("DTSTART;TZID=America/Los_Angeles:20140423T120000");

还有这个:

SimpleDateFormat sdf = new SimpleDateFormat("'DTSTART;TZID='z':'yyyyMMdd'T'hhmmss");
Date start = sdf.parse("DTSTART;TZID=America/Los_Angeles:20140423T120000");

但它仍然无效.我认为问题出在America/Los_Angeles.你能帮我吗？

谢谢

Answer 1

使用TimeZone尝试这个.

注意:在执行此操作之前,您必须拆分日期字符串.

    SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd'T'hhmmss");

    TimeZone tz = TimeZone.getTimeZone("America/Los_Angeles");
    sdf.setTimeZone(tz);

    Date start = sdf.parse("20140423T120000");

在SimpleDateFormat模式Z代表RFC 822 4-digit time zone

有关更多信息,请查看SimpleDateFormat #timezone.

Answer 2

如果您寻找一个解决方案如何在一个步骤中解析整个给定字符串,那么Java 8提供此选项(不支持模式符号VSimpleDateFormat):

// V = timezone-id, HH instead of hh for 24-hour-clock, u for proleptic ISO-year
DateTimeFormatter dtf = 
  DateTimeFormatter.ofPattern("'DTSTART;TZID='VV:uuuuMMdd'T'HHmmss");
ZonedDateTime zdt = 
  ZonedDateTime.parse("DTSTART;TZID=America/Los_Angeles:20140423T120000", dtf);
Instant instant = zdt.toInstant();

// if you really need the old class java.util.Date
Date jdkDate = Date.from(instant);