op4j is a nice little library for all those of us who need to work with collections. Here is a little example:
Calendar now = Calendar.getInstance();
Set<Calendar> set =
Op.on(list)
.toSet()
.map(FnString.toCalendar("dd/MM/yyyy"))
.removeAllNullOrTrue(FnCalendar.after(now))
.get();
That takes a list of strings, converts them to Calendar instances and removes all dates which are null or in the future. Questions?
Posted by digulla 
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