code: public void updateServiceMetadata(String serviceName, String providerAddress,
              Map<String, String> metadata) {
          getServiceDirectoryClient().updateInstanceMetadata(serviceName, providerAddress,
                  metadata, disableOwnerError);
      }
docs: Update the metadata attribute of the ProvidedServiceInstance
  The ProvidedServiceInstance is uniquely identified by serviceName and providerAddress
  
  @param serviceName
  the serviceName of the ProvidedServiceInstance.
  @param providerAddress
  The IP address or FQDN that the instance is running on.
  @param metadata
  the meta data.