@Override
 public Range getRange(String rt, String focuser)
     throws DeviceOperationFailedException, FocuserTeleoperationException {
   try {
     return (Range) this.invokeGetOperation(GetRangeOperation.class, rt, focuser);
   } catch (DeviceOperationFailedException e) {
     throw e;
   } catch (ActionException e) {
     throw new FocuserTeleoperationException(e.getAction());
   }
 }
 @Override
 public void moveRelative(String rt, String focuser, long steps)
     throws DeviceOperationFailedException, FocuserTeleoperationException {
   try {
     this.invokeSetOperation(MoveRelativeOperation.class, rt, focuser, steps);
   } catch (DeviceOperationFailedException e) {
     throw e;
   } catch (ActionException e) {
     throw new FocuserTeleoperationException(e.getAction());
   }
 }