If you allowed setting precision in the internal representation of the number and not just how it is displayed you run into all kinds of nasty rounding issues, because rounding might be employed multiple times over the course of a calculation sequence and not just once at the end.
It could also play havoc with portability and distributed processing, part of the power of
java is that things like number formats are common across all machines. An integer is always "x" bits, etc.
Byron Estes<br />Sun Certified Enterprise Architect<br />Senior Consulant<br />Blackwell Consulting Services<br />Chicago, IL<br /><a href="http://www.bcsinc.com" target="_blank" rel="nofollow">www.bcsinc.com</a>