code: @Override
    public void filter(IKeyValuePair keyValuePair) {
      String value = keyValuePair.getValue();
      if (value != null) {
        keyValuePair.setValue(value + " [" + keyValuePair.getKey() + "]");
      } else {
        keyValuePair.setValue("[" + keyValuePair.getKey() + "]");
      }
    }
docs: {@inheritDoc}