docs: public static void validateProvidedServiceInstance(
              ProvidedServiceInstance serviceInstance) throws ServiceException {
          
          if (serviceInstance == null) {
              throw new ServiceException(
                      ErrorCode.SERVICE_DIRECTORY_NULL_ARGUMENT_ERROR,
                      ErrorCode.SERVICE_DIRECTORY_NULL_ARGUMENT_ERROR.getMessageTemplate(),
                      "service instance");
          }
                 
          validateServiceName(serviceInstance.getServiceName());
          validateURI(serviceInstance.getUri());
          validateAddress(serviceInstance.getAddress());
          
          if (serviceInstance.getMetadata()!=null) { //allow metadata as null
              validateMetadata(serviceInstance.getMetadata());
          }
      }