This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
I'm not quite sure what you're asking here. If you prevent values over 99 inches, why is 13.5 inches a special case worth mentioning? Is that you really mean than only values between 0 and 99.9 or so are allowed?
If so, a converter isn't what you need. You need a RangeValidator. Basic JSF stuff.
An IDE is no substitute for an Intelligent Developer.