@SuppressWarnings("unchecked")
 protected void setSensor(Object v) {
   if (v == FeedConfig.UNCHANGED) {
     // nothing
   } else if (v == FeedConfig.REMOVE) {
     ((EntityInternal) entity).removeAttribute(sensor);
   } else if (sensor == FeedConfig.NO_SENSOR) {
     // nothing
   } else {
     entity.setAttribute(sensor, TypeCoercions.coerce(v, sensor.getType()));
   }
 }