code: @Beta
    @SuppressWarnings("GoodTime") // reading system time without TimeSource
    public static void touch(File file) throws IOException {
      checkNotNull(file);
      if (!file.createNewFile() && !file.setLastModified(System.currentTimeMillis())) {
        throw new IOException("Unable to update modification time of " + file);
      }
    }
docs: Creates an empty file or updates the last updated timestamp on the same as the unix command of
  the same name.
  
  @param file the file to create or update
  @throws IOException if an I/O error occurs