dmfs
Wrong instance returned by RecurrenceSetIterator
While iterating through instances using RecurrenceSetIterator, if start time provided is not a valid instance, then start time is also returned as one of the instance. Is this expected ? If Yes, can some way be suggested to find only valid dates ? Example code :
public static void main(String[] args) throws InvalidRecurrenceRuleException {
ZonedDateTime startTime = ZonedDateTime.parse("2022-04-27T00:38:20Z", DateTimeFormatter.ISO_OFFSET_DATE_TIME);
String rrule = "FREQ=WEEKLY;INTERVAL=1;BYDAY=TH";
String timezone = "UTC";
ZoneId zoneId = ZoneId.of(timezone);
RecurrenceSet recurrenceSet = new RecurrenceSet();
RecurrenceRule recurrenceRule = new RecurrenceRule(rrule);
recurrenceSet.addInstances(new RecurrenceRuleAdapter(recurrenceRule));
RecurrenceSetIterator it = recurrenceSet.iterator(TimeZone.getTimeZone(timezone), startTime.toInstant().toEpochMilli());
for (int itr = 0; itr < 10; ++itr) {
ZonedDateTime instant = Instant.ofEpochMilli(it.next()).atZone(zoneId);
System.out.println("Instant " + itr + ", date: " + instant + ", day: " + instant.getDayOfWeek());
}
}
Outputs :
Instant 0, date: 2022-04-27T00:38:20Z[UTC], day: WEDNESDAY
Instant 1, date: 2022-04-28T00:38:20Z[UTC], day: THURSDAY
Instant 2, date: 2022-05-05T00:38:20Z[UTC], day: THURSDAY
Instant 3, date: 2022-05-12T00:38:20Z[UTC], day: THURSDAY
Instant 4, date: 2022-05-19T00:38:20Z[UTC], day: THURSDAY
Instant 5, date: 2022-05-26T00:38:20Z[UTC], day: THURSDAY
Instant 6, date: 2022-06-02T00:38:20Z[UTC], day: THURSDAY
Instant 7, date: 2022-06-09T00:38:20Z[UTC], day: THURSDAY
Instant 8, date: 2022-06-16T00:38:20Z[UTC], day: THURSDAY
Instant 9, date: 2022-06-23T00:38:20Z[UTC], day: THURSDAY
But wednesday is not a valid instance.
When i expand instances by adding same input on : https://recurrence-expansion-service.appspot.com/ , then instances provided are correct, can you please suggest the correct way used in website above ?
While iterating through instances using RecurrenceSetIterator, if start time provided is not a valid instance, then start time is also returned as one of the instance. Is this expected ? If Yes, can some way be suggested to find only valid dates ? Example code :
public static void main(String[] args) throws InvalidRecurrenceRuleException { ZonedDateTime startTime = ZonedDateTime.parse("2022-04-27T00:38:20Z", DateTimeFormatter.ISO_OFFSET_DATE_TIME); String rrule = "FREQ=WEEKLY;INTERVAL=1;BYDAY=TH"; String timezone = "UTC"; ZoneId zoneId = ZoneId.of(timezone); RecurrenceSet recurrenceSet = new RecurrenceSet(); RecurrenceRule recurrenceRule = new RecurrenceRule(rrule); recurrenceSet.addInstances(new RecurrenceRuleAdapter(recurrenceRule)); RecurrenceSetIterator it = recurrenceSet.iterator(TimeZone.getTimeZone(timezone), startTime.toInstant().toEpochMilli()); for (int itr = 0; itr < 10; ++itr) { ZonedDateTime instant = Instant.ofEpochMilli(it.next()).atZone(zoneId); System.out.println("Instant " + itr + ", date: " + instant + ", day: " + instant.getDayOfWeek()); } }Outputs :
Instant 0, date: 2022-04-27T00:38:20Z[UTC], day: WEDNESDAY Instant 1, date: 2022-04-28T00:38:20Z[UTC], day: THURSDAY Instant 2, date: 2022-05-05T00:38:20Z[UTC], day: THURSDAY Instant 3, date: 2022-05-12T00:38:20Z[UTC], day: THURSDAY Instant 4, date: 2022-05-19T00:38:20Z[UTC], day: THURSDAY Instant 5, date: 2022-05-26T00:38:20Z[UTC], day: THURSDAY Instant 6, date: 2022-06-02T00:38:20Z[UTC], day: THURSDAY Instant 7, date: 2022-06-09T00:38:20Z[UTC], day: THURSDAY Instant 8, date: 2022-06-16T00:38:20Z[UTC], day: THURSDAY Instant 9, date: 2022-06-23T00:38:20Z[UTC], day: THURSDAYBut wednesday is not a valid instance.
When i expand instances by adding same input on : https://recurrence-expansion-service.appspot.com/ , then instances provided are correct, can you please suggest the correct way used in website above ?
Have you solved the problem? I have the same question
I have rewritten the recurrence set iterator code. Now you can chose to iterate or omit the first instance if it's not synchronized with the rule. Hope this works for everyone. Please check out README.md for guidance and let me know if you have any questions.
