docs: @Override
      public ExecutorService newSingleThreadExecutorService() {
  
          // create new single thread executor service
          ExecutorService singleThreadExecutorService = Executors.newSingleThreadExecutor(getThreadFactory("pi4j-single-executor-%d"));
  
          // add new instance to managed collection
          singleThreadExecutorServices.add(singleThreadExecutorService);
  
          // return new executor service
          return singleThreadExecutorService;
      }