private static IIdentifierRenamer loadHelper(String className, IFernflowerLogger logger) {
    if (className != null) {
      try {
        Class<?> renamerClass = Fernflower.class.getClassLoader().loadClass(className);
        return (IIdentifierRenamer) renamerClass.getDeclaredConstructor().newInstance();
      }
      catch (Exception e) {
        logger.writeMessage("Cannot load renamer '" + className + "'", IFernflowerLogger.Severity.WARN, e);
      }
    }

    return new ConverterHelper();
  }
private static IIdentifierRenamer loadHelper(String className, IFernflowerLogger logger)