code: @Deprecated
      public void stopWatching(File file) {
          if (file == null) {
              throw new IllegalArgumentException("Null file argument");
          }
          synchronized (mutex) {
              stopWatchingInternal(file.toPath());
          }
      }
docs: Stop watching a specific file.
  
  @param file The file to be watched.
  @deprecated Use {@link #removeWatcher(Listener)} and let it clean up watched
  files itself.