Endpoint vs. Observer Coprocessors

[Pavel Hančar]

Hello,
I've just started to discover coprocessors. Namely the classes
BaseEndpointCoprocessor and BaseRegionObserver. I need the postPut() method
and than some special user calls. So I need both, but I want to have my
data in one common variable. What's the easiest way to manage? Do I have to
Implement my own Base...Coprocessor class?
 Best wishes,
  Pavel Hančar