Why are so many classes and methods in Wicket final?
Classes and methods in Wicket are generally declared as final until the need for extensibility is well understood. While this defensive approach may seem obsessive to some, the major benefit is that classes and methods which haven’t been designed for extension cannot be extended until the problem(s) at hand are examined by the Wicket development team. This helps to ensure that the best approach is taken. Sometimes, straightforward extension is not the best approach. Sometimes, features of the API have been misapplied or misunderstood. It’s best to catch this early. While this does provoke more discussion and sometimes a bit of annoyance, the discussion generally improves Wicket and will help ensure greater backwards compatibility in the future. It’s really a matter of how the development team manages API commitments. By making fewer commitments in the API in terms of extension points, we are more likely to be able to support those extension points that we do allow in the future. We are
