Jollyday Regions of Holiday - collections

Question

I'm using jollyday for checking the holidays for showing them in a calendar.
With that i'm getting the Holidays as a Set, by calling the Method with the year and the regionCode:
HolidayManager m = HolidayManager.getInstance(HolidayCalendar.GERMANY);
Set<Holiday> holidays =m.getHolidays(year, regionCode)
Perhaps I have to do this multiple times for different regionCodes, but all comes in one Set.
After I have all the holidays i want to make a Map with Informations to this Holiday:
Map getCalendarProperties(Holiday holiday) {
HolidayManager m = HolidayManager.getInstance(HolidayCalendar.GERMANY);
Map a = [:]
a.tooltip = "<div class='row'>" +
"<div class='col-xs-6'><b>${holiday.description}</b></div>" +
"<div class='col-xs-6'> </div>" +
"</div>"
a.date = holiday?.date.toString(DateTimeFormat.forPattern("YYYY-MM-dd"));
return a
}
I would like to write in the tooltip in which regions of Germany this Holiday is available.
I could check the Date for every Region, but this is to much for that.
Any suggestions?

Answer 1

Well, since the API of jollyday does not offer the view you want, and it's not using a proper multimap which could do this by itself, you have to just construct it. Do something like this (untested code, my Groovy is rusty):
regionsForHolidays = [:]
regions.each{ region ->
holidays = m.getHolidays(year, region)
holidays.each{ holiday ->
set = regionsForHolidays[holiday]
if(set==null){
set = []
regionsForHolidays[holiday] = set
}
set.add(region)
}
}
Then you can query regionsForHolidays[holiday] and get a set of regions.