Currently ical4j may throw two exception classes in case of bad input:
1. sometimes its ParseException (example: "FREQ=YEARLY;BYMONTH=5L")
2. sometimes its IllegalArgumentException (example: "FREQ=YEARLY;BYMONTH=0")

Is there any value in separating the two? If not, I'll prepare a patch to always throw ParseException in such cases.

 
Last edit: Grigory Yakushev 2013-06-20