code: private static List<String> loadCollectionListFile(final String collectionListFile) {
          try (BufferedReader reader = new BufferedReader(new FileReader(collectionListFile))){
              return reader.lines()
                      .map(String::trim)
                      .filter(line -> !line.isEmpty())
                      .filter(line -> !line.startsWith(ARGUMENT_FILE_COMMENT))
                      .collect(Collectors.toList());
          } catch (final IOException e) {
              throw new CommandLineException("I/O error loading list file:" + collectionListFile, e);
          }
      }
docs: Read a list file and return a list of the collection values contained in it
  Any line that starts with {@link CommandLineArgumentParser#ARGUMENT_FILE_COMMENT} is ignored.
  
  @param collectionListFile a text file containing list values
  @return false if a fatal error occurred