Implement Handler (base) / GetHandler (child) class.

[StokesAsselborn]

[StokesAsselborn]

To not store different type of handlers in the client class, the easiest would be to provide a single interface.

Base class Handler
Child class GetHandler, PostHandler, DeleteHandler

The base class provides to virtual methods :
onRead()
onWrite()

Then these functions are overloaded in the child classes.

[StokesAsselborn]

class Handler, class GetHandler added

To be done : PostHandler and DeleteHandler

[StokesAsselborn]

Can be closed following the #42