Can there be in whatever way to request pipeline processors in Apache Wicket? Possibly by having an open-source framework that combines with Wicket?

I wish to check demands before my webpages are made.

In Wicket 1.4.x, you need to extend [Web]RequestCycle, to ensure that an override the hook techniques (onBeginRequest(), onEndRequest(), onAfterTargetsDetached(), etc.), and override Application.newRequestCycle() to come back the custom class.

In Wicket 1.5.x, this mechanism continues to be refactored, so that you can just implement the RequestCycleListener, which supplies exactly the same hooks. This new mechanism is way better, since compose and reuse audience.

In Wicket 1.4.x (have no idea if the continues to be stored in 1.5) you've RequestCycle#onBeginRequest() and RequestCycle#onEndRequest() that you could override.