docs: public static synchronized List getPropertyNames(String entityTypeName) {
          if (propertyNames != null) {
              return propertyNames;
          } else {
              {
                  List names = new ArrayList();
                  names.add("value");
                  names.add("lang");
                  propertyNames = Collections.unmodifiableList(names);
                  return propertyNames;
              }
          }
      }