code: private Config findAndLoadGlobalConfigInDirectory(Path path, Config fallback) throws IOException {
      FileStatus[] files = this.fs.listStatus(path, GLOBAL_PATH_FILTER);
      if (files == null) {
        log.warn("Could not list files at path " + path);
        return ConfigFactory.empty();
      }
      if (files.length > 1) {
        throw new IOException("Found more than one global properties file at path " + path);
      }
      if (files.length == 0) {
        return fallback;
      }
      if (GLOBAL_HOCON_PATH_FILTER.accept(files[0].getPath())) {
        return loadHoconConfigWithFallback(files[0].getPath(), fallback);
      } else if (GLOBAL_PROPS_PATH_FILTER.accept(files[0].getPath())) {
        return loadJavaPropsWithFallback(files[0].getPath(), fallback);
      } else {
        throw new IllegalStateException("Unsupported global configuration file: " + files[0].getPath());
      }
    }
docs: Find at most one *.properties file in the input {@link Path} and load it using fallback as fallback.
  @return The {@link Config} in path with sysProps as fallback.
  @throws IOException