code: public synchronized void destroy()
  	{
  		if (state == DESTROYED)
  			return;
  		if (state != DISCONNECTED)
  			try {
  				tl.disconnect(this);
  			}
  			catch (final KNXLinkClosedException e) {
  				// we already should've been destroyed on catching this exception
  			}
  		setState(DESTROYED);
  		tl.destroyDestination(this);
  	}
docs: Destroys this destination.
  <p>
  If the connection state is connected, it will be disconnected. The connection state
  is set to {@link #DESTROYED}. The associated transport layer is notified through
  {@link TransportLayer#destroyDestination(Destination)}. <br>
  On an already destroyed destination, no action is performed.