code: public void addForeigerKey(String key) {
      String[] foreigers = new String[foreigerKeys.length + 1];
      int i = 0;
      for (; i < foreigerKeys.length; i++) {
        foreigers[i] = foreigerKeys[i];
      }
      foreigers[i] = key;
      foreigerKeys = foreigers;
    }
docs: <p>
  addForeigerKey.
  </p>
  
  @param key a {@link java.lang.String} object.