Absolutely! You are welcome to bring your own coffee and filters (bring the small ones) to make your own. You will also be provided with some coffee and tea for your room.
Disney has a reputation for many wonderful things, but it tends to fall a bit short when it comes to coffee. While I have no problem with the coffee from the Roaring Forks Snacks (where you can refill the mugs), it isn't the same as Starbucks.
If you really have a craving for some tasty coffee, I'd like to suggest the coffee bar/Kona Cafe at the Polynesian, the Writer's Stop or Starring Rolls at Disney's Hollywood Studios, the coffee carts at the Animal Kingdom, the coffee bar at the Contemporary, and the coffee kiosks throughout Epcot's World Showcase.
Have a fantastic trip; the Wilderness Lodge is amazing!!