code: public void setTransmitters(Collection<Transmitter> transmitters) {
      if (transmitters == null) {
        this.transmitters = null;
        return;
      }
      int size = transmitters.size();
      if (size == 0) {
        this.transmitters = null;
        return;
      }
      this.transmitters = transmitters.toArray(new Transmitter[] {});
  
    }
docs: Sets the transmitters for this rule. Any previous values are discarded.
  
  @param transmitters
  the new transmitters.