Sun Java System Application Server Enterprise Edition 8.1 2005Q2 Performance Tuning Guide

Declare Methods as final Only If Necessary

Modern optimizing dynamic compilers can perform inlining and other inter-procedural optimizations, even if Java methods are not declared final. Use the keyword final as it was originally intended: for program architecture reasons and maintainability.

Only if you are absolutely certain that a method must not be overridden, use the final keyword.