public BSDPathWatchService() {
   try {
     String propertyValue =
         System.getProperty(
             "name.pachler.io.file.BSDPathWatchService.pollingIntervalMillis",
             Long.toString(DEFAULT_POLLING_INTERVAL_MILLIS));
     pollingIntervalMillis = Long.parseLong(propertyValue);
   } catch (Throwable t) {
     // ignore, pllingIntervalMillis will still have its default value.
   }
   open();
 }