带有可选冒号分隔符的时区的 Java DateTimeFormatter？

Java DateTimeFormatter for time zone with an optional colon separator?

提问by Nelson G.

I'm trying to build a DateTimeFormatter that can accepts offset with colon or offset without colon.

我正在尝试构建一个 DateTimeFormatter，它可以接受带冒号的偏移量或不带冒号的偏移量。

Is there a way to pass this test :

有没有办法通过这个测试：

DateTimeFormatter dateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss[X]");
dateTimeFormatter.parse("2015-01-28T10:21:44+0100"); // OK
dateTimeFormatter.parse("2015-01-28T10:21:44+01:00"); // KO

回答by Titus

This: yyyy-MM-dd'T'HH:mm:ss[XXX][X]seems to work.

这：yyyy-MM-dd'T'HH:mm:ss[XXX][X]似乎工作。

DateTimeFormatter dateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss[XXX][X]");
dateTimeFormatter.parse("2015-01-28T10:21:44+0100");
dateTimeFormatter.parse("2015-01-28T10:21:44+01:00");

回答by Philippe B.

Here is the ultimate pattern matching for pretty everything looking like an ISO string date !

这是几乎所有看起来像 ISO 字符串日期的最终模式匹配！

"[yyyyMMdd][yyyy-MM-dd][yyyy-DDD]['T'[HHmmss][HHmm][HH:mm:ss][HH:mm][.SSSSSSSSS][.SSSSSS][.SSS][.SS][.S]][OOOO][O][z][XXXXX][XXXX]['['VV']']"

It works for the following list of tests except for the two in comments but I still don't know why...

除了评论中的两个之外，它适用于以下测试列表，但我仍然不知道为什么......

    ZonedDateTime dt = DateTimeUtils.parse("2016-10-27T16:36:08.993+02:00:00[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993+02:00[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993+020000[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993+0200[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993+0000[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993Z[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993GMT+1[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993UTC[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993PST[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993[Europe/Paris]");

    dt = DateTimeUtils.parse("2016-10-27T16:36:08+02:00[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08+020000[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08+0200[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08+0000[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08Z[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08GMT+1[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08UTC[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08PST[Europe/Paris]");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08[Europe/Paris]");

    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993+02:00:00");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993+02:00");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993+020000");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993+0200");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993+0000");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993Z");
    //dt = DateTimeUtils.parse("2016-10-27T16:36:08.993GMT+1");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993UTC");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993PST");

    dt = DateTimeUtils.parse("2016-10-27T16:36:08.993");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.000993");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08.000000993");

    dt = DateTimeUtils.parse("2016-10-27T16:36:08+02:00:00");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08+02:00");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08+020000");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08+0200");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08+0000");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08Z");
    //dt = DateTimeUtils.parse("2016-10-27T16:36:08GMT+1");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08UTC");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08PST");
    dt = DateTimeUtils.parse("2016-10-27T16:36:08");

    dt = DateTimeUtils.parse("2016-100T16:36:08Z");
    dt = DateTimeUtils.parse("2016-100T16:36.1Z");
    dt = DateTimeUtils.parse("2016-10-27");

    dt = DateTimeUtils.parse("20161223T163608");
    dt = DateTimeUtils.parse("20161223T1636");

And the parse method itself :

和 parse 方法本身：

public static ZonedDateTime parse(CharSequence text) {
    TemporalAccessor temporalAccessor = LOOSE_ISO_DATE_TIME_ZONE_PARSER.parseBest(text, ZonedDateTime::from, LocalDateTime::from, LocalDate::from);
    if (temporalAccessor instanceof ZonedDateTime) {
        return ((ZonedDateTime) temporalAccessor);
    }
    if (temporalAccessor instanceof LocalDateTime) {
        return ((LocalDateTime) temporalAccessor).atZone(ZoneId.systemDefault());
    }
    return ((LocalDate) temporalAccessor).atStartOfDay(ZoneId.systemDefault());
}