I was using DateFormatSymbols's getMonths() for retrieving months array.
But to my surprise, the array returned by this method has length of 13.
when i print values from this array, a blank text is present as last value(13th).
This is the hidden month that exists to explain how you are suppose to complete 13 months worth of work in only 12. It only exists in the imagination of executives and project managers so they don't feel guilty for compressing time lines too much.