<p>I've implemented a stopwatch that works fine without considering that bank holidays and weekends shouldn't be counted in the total duration. I was looking for some open-source library where I could get the elapsed time, passing a start instant, end instant and a set of bank holidays (weekends aren't counted in). The only library that makes me things easier is net.sf.jtemporal, but I have still to amplify the functionality.
Could anyone tell me if there is some useful library to get the wanted functionality?</p>

Do you only count Bank Hours too?  9AM - 3PM?  Or is it 24 hours a day?