code: public Observable<ServiceResponse<HybridRunbookWorkerGroupInner>> updateWithServiceResponseAsync(String resourceGroupName, String automationAccountName, String hybridRunbookWorkerGroupName, RunAsCredentialAssociationProperty credential) {
          if (resourceGroupName == null) {
              throw new IllegalArgumentException("Parameter resourceGroupName is required and cannot be null.");
          }
          if (automationAccountName == null) {
              throw new IllegalArgumentException("Parameter automationAccountName is required and cannot be null.");
          }
          if (hybridRunbookWorkerGroupName == null) {
              throw new IllegalArgumentException("Parameter hybridRunbookWorkerGroupName is required and cannot be null.");
          }
          if (this.client.subscriptionId() == null) {
              throw new IllegalArgumentException("Parameter this.client.subscriptionId() is required and cannot be null.");
          }
          Validator.validate(credential);
          final String apiVersion = "2015-10-31";
          HybridRunbookWorkerGroupUpdateParameters parameters = new HybridRunbookWorkerGroupUpdateParameters();
          parameters.withCredential(credential);
          return service.update(resourceGroupName, automationAccountName, hybridRunbookWorkerGroupName, this.client.subscriptionId(), apiVersion, this.client.acceptLanguage(), parameters, this.client.userAgent())
              .flatMap(new Func1<Response<ResponseBody>, Observable<ServiceResponse<HybridRunbookWorkerGroupInner>>>() {
                  @Override
                  public Observable<ServiceResponse<HybridRunbookWorkerGroupInner>> call(Response<ResponseBody> response) {
                      try {
                          ServiceResponse<HybridRunbookWorkerGroupInner> clientResponse = updateDelegate(response);
                          return Observable.just(clientResponse);
                      } catch (Throwable t) {
                          return Observable.error(t);
                      }
                  }
              });
      }
docs: Update a hybrid runbook worker group.
  
  @param resourceGroupName Name of an Azure Resource group.
  @param automationAccountName The name of the automation account.
  @param hybridRunbookWorkerGroupName The hybrid runbook worker group name
  @param credential Sets the credential of a worker group.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the HybridRunbookWorkerGroupInner object