code: public void beginRegenerateKey(String resourceGroupName, String accountName, KeyKind keyKind) {
          beginRegenerateKeyWithServiceResponseAsync(resourceGroupName, accountName, keyKind).toBlocking().single().body();
      }
docs: Regenerates an access key for the specified Azure Cosmos DB database account.
  
  @param resourceGroupName Name of an Azure resource group.
  @param accountName Cosmos DB database account name.
  @param keyKind The access key to regenerate. Possible values include: 'primary', 'secondary', 'primaryReadonly', 'secondaryReadonly'
  @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