code: public DomainSharedAccessKeysInner regenerateKey(String resourceGroupName, String domainName, String keyName) {
          return regenerateKeyWithServiceResponseAsync(resourceGroupName, domainName, keyName).toBlocking().single().body();
      }
docs: Regenerate key for a domain.
  Regenerate a shared access key for a domain.
  
  @param resourceGroupName The name of the resource group within the user's subscription.
  @param domainName Name of the domain
  @param keyName Key name to regenerate key1 or key2
  @throws IllegalArgumentException thrown if parameters fail the validation
  @throws CloudException thrown if the request is rejected by server
  @throws RuntimeException all other wrapped checked exceptions if the request fails to be sent
  @return the DomainSharedAccessKeysInner object if successful.