code: public boolean isSet(PropertyKey key) {
      if (isSetByUser(key)) {
        return true;
      }
      // In case key is not the reference to the original key
      return PropertyKey.fromString(key.toString()).getDefaultValue() != null;
    }
docs: Checks if there is a value set for the given key.
  
  @param key the key to check
  @return true if there is value for the key, false otherwise