make Parameters as interface and i have full control over it's behavior. Also i think when injecting dependecies over constructor it's related to the servlet scope but what if i have a dependency that must live only in the request and has a request dependecy like Parameters depends on HttpServletRequest. Well the solution of mine is to overload the method and inject the dependency. In the production we just make new instance of the parameters implementation ( RequestParameters for example ) and pass the HttpServletRequest.