I have an application which needs to find the user location, and location is fetched in various classes, so i have written a separate class(Not an Activity
You can not override it. This method is only available for Activity and Fragments. But you can create a static method inside your Location class and call it from your activity/fragment's overridden onRequestPermissionResult method.
I have made a custom implementation for Location combined with permission. You can also use a library called Let for permissions.