assuming the wheel is off and by hub you mean disk, then fairly straight forward. i would replace the pads at the same time, so you would need 2 disks £20-40 pads £10-30. remove caliper remove caliper bracket, remove disk. fit new disks and pads. Remeber to bleed the caliper when pushing the piston back. ABS won't make much difference as long as you support the caliper and no cables or pipes to it are tight.
HTH if I understood the question corectly.