code: private void loadProperties(final String filename, final int depth) {
      logger.warning("Loading file '" + filename + "'");
      final Properties properties = new Properties();
      try {
        // Load our properties file.
        for (final InputStream io : getInputStreamsForFile(filename)) {
          properties.load(io);
          logger.info("Property file loaded successfully (" + filename + ")");
          io.close();
        }
      }
      catch (final java.io.FileNotFoundException ex) {
        logger.warning("Property file not found (" + filename + ")");
      }
      catch (final java.io.IOException ex) {
        logger.warning("IOException loading file: " + ex.getMessage());
        logger.log(Logging.Priority.FATAL.getLevel(), "Error occured while loading properties file (" + filename + ")", ex);
      }
      allProperties.putAll(properties);
      final String includeFiles[] = readIncludeFiles(filename, depth);
      for (final String includeFile : includeFiles) {
        loadProperties(includeFile, depth + 1);
      }
    }
docs: Loads the given property file, plus any files that are referenced by
  #include statements