多个实现语句与接口扩展

I have a web app with a "Semi-MVC" structure (It consists of Classes, Controllers, Views) and would like to know how to solve one problem.

My controllers are currently in this format:

class {ControllerName} extends Core implements PostController {

My PostController starts like this:

interface PostController extends Controller {

Now, would it be better to just structure the controllers in this way:

class {ControllerName} extends Core implements Controller, PostController {

There is only one disadvantage of the latter that I could think off is harder refactoring.

Could anyone shine some light on this?

Thank you.