public MrNeighborhood getNeighborhood() {
   return machine == null ? null : machine.getNeighborhood();
 }
 public MrLocation getLocation() {
   return machine == null ? null : machine.getLocation();
 }
 public int getMachineMoveCost() {
   return machine == null ? 0 : originalMachine.getMoveCostTo(machine);
 }