code: private void modifyKeyPath(String fileName, String ice_root) throws IOException {
      FileInputStream in = null;
      Properties sslProps;
      try {
        in = new FileInputStream(fileName);
        sslProps = new Properties();
        sslProps.load(in);
      } finally {
        if (in != null) {
          in.close();
        }
      }
  
      subPath("h2o_ssl_jks_internal", sslProps, ice_root);
      subPath("h2o_ssl_jts", sslProps, ice_root);
  
      FileOutputStream out = null;
      try {
        out = new FileOutputStream(fileName);
        sslProps.store(out, null);
      } finally {
        if (out != null) {
          out.close();
        }
      }
    }
docs: ==============================================================================