private void validateKeys(
      PackageMaterialProperties configDefinedByPlugin,
      PackageMaterialProperties configProvidedByUser,
      ValidationResultMessage validationResultMessage) {
    List<String> invalidKeys = new ArrayList<String>();

    for (String key : configProvidedByUser.keys()) {
      if (!configDefinedByPlugin.hasKey(key)) {
        invalidKeys.add(key);
      }
    }
    if (!invalidKeys.isEmpty()) {
      validationResultMessage.addError(
          create(
              String.format(
                  "Unsupported key(s) found : %s. Allowed key(s) are : %s",
                  join(invalidKeys), join(configDefinedByPlugin.keys()))));
    }
  }