无法通过 api (Java) 在谷歌日历中设置正确的重复周期

Question

DateTime startDateTime = new DateTime("2020-12-16T09:00:00-03:00");
EventDateTime start = new EventDateTime()
            .setDateTime(startDateTime)
            .setTimeZone("Europe/Minsk");
event.setStart(start);

DateTime endDateTime = new DateTime("2020-12-16T17:00:00-03:00");
EventDateTime end = new EventDateTime()
            .setDateTime(endDateTime)
            .setTimeZone("Europe/Minsk");
event.setEnd(end);
List<String> recurrences = new ArrayList<>(Arrays.asList("RDATE;VALUE=PERIOD:19960403T020000Z/19960403T040000Z,19960404T010000Z/PT3H"));

Have a problem with setting recurrence. After executing this code duration in following events is setting like in main event and rule in string is ignoring. Can anybody help me solve that?

Answer 1

RFC5545 specifies:

If the "RDATE" property is specified as a PERIOD value the duration of the recurrence instance will be the one specified by the "RDATE" property, and not the duration of the recurrence instance defined by the "DTSTART" property.

The Calendar API Events resource specifies:

List of RRULE, EXRULE, RDATE and EXDATE lines for a recurring event, as specified in RFC5545. Note that DTSTART and DTEND lines are not allowed in this field; event start and end times are specified in the start and end fields. This field is omitted for single events or instances of recurring events.

In other words, VALUE=PERIOD does not seem to be compatible with the Google Calendar API, because it overwrites DTSTART .

I recommend you to have a look at the Calendar API documentation for recurring events to adjust your recurrent rule accordingly.

For Java, please also keep in mind that it is important to use the UTC date correctly, see here .