code: private Config loadJavaPropsWithFallback(Path propertiesPath, Config fallback) throws IOException {
  
      PropertiesConfiguration propertiesConfiguration = new PropertiesConfiguration();
      try (InputStreamReader inputStreamReader = new InputStreamReader(this.fs.open(propertiesPath),
          Charsets.UTF_8)) {
        propertiesConfiguration.setDelimiterParsingDisabled(ConfigUtils.getBoolean(fallback,
      		  PROPERTY_DELIMITER_PARSING_ENABLED_KEY, DEFAULT_PROPERTY_DELIMITER_PARSING_ENABLED_KEY));
        propertiesConfiguration.load(inputStreamReader);
  
        Config configFromProps =
            ConfigUtils.propertiesToConfig(ConfigurationConverter.getProperties(propertiesConfiguration));
  
        return ConfigFactory.parseMap(ImmutableMap.of(ConfigurationKeys.JOB_CONFIG_FILE_PATH_KEY,
            PathUtils.getPathWithoutSchemeAndAuthority(propertiesPath).toString()))
            .withFallback(configFromProps)
            .withFallback(fallback);
      } catch (ConfigurationException ce) {
        throw new IOException(ce);
      }
    }
docs: Load a {@link Properties} compatible path using fallback as fallback.
  @return The {@link Config} in path with fallback as fallback.
  @throws IOException