docs: synchronized void clearInstance() {
  		for (ServerSocket next : myControlSockets) {
  			ourLog.info("Releasing control port: {}", next.getLocalPort());
  			try {
  				next.close();
  			} catch (IOException theE) {
  				// ignore
  			}
  		}
  		myControlSockets.clear();
  		myCurrentControlSocketPort = null;
  	}