This week's book giveaway is in the Performance forum. We're giving away four copies of The Java Performance Companion and have Charlie Hunt, Monica Beckwith, Poonam Parhar, & Bengt Rutisson on-line! See this thread for details.
Check out NavigationFilter instead. This class can be set for text components, and disallow the caret to be set at certain locations. However, you would have known that you could use this class had you gone to the Protected Text Component link that Darryl mentioned in your previous thread.