public void setWatched(Set<Path> paths) {
    if (paths == null || paths.isEmpty()) {
      return;
    }
    paths = paths.stream().map(FileWatcher::normalize).collect(Collectors.toSet());
    for (var toWatch : paths) {
      if (!watching(toWatch)) {
        watch(toWatch);
      }
    }
    for (var watching : Set.copyOf(modificationTimes.keySet())) {
      if (!paths.contains(watching)) {
        unwatch(watching);
      }
    }
  }
Ensures we are only watching {@code paths} provided.
planetiler-core/src/main/java/com/onthegomap/planetiler/util/FileWatcher.java