code: public Observable<BackupLongTermRetentionVaultInner> beginCreateOrUpdateAsync(String resourceGroupName, String serverName, String recoveryServicesVaultResourceId) {
          return beginCreateOrUpdateWithServiceResponseAsync(resourceGroupName, serverName, recoveryServicesVaultResourceId).map(new Func1<ServiceResponse<BackupLongTermRetentionVaultInner>, BackupLongTermRetentionVaultInner>() {
              @Override
              public BackupLongTermRetentionVaultInner call(ServiceResponse<BackupLongTermRetentionVaultInner> response) {
                  return response.body();
              }
          });
      }
docs: Updates a server backup long term retention vault.
  
  @param resourceGroupName The name of the resource group that contains the resource. You can obtain this value from the Azure Resource Manager API or the portal.
  @param serverName The name of the server.
  @param recoveryServicesVaultResourceId The azure recovery services vault resource id
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the BackupLongTermRetentionVaultInner object