code: public Observable<ServiceResponse<WorkItemConfigurationInner>> getDefaultWithServiceResponseAsync(String resourceGroupName, String resourceName) {
          if (resourceGroupName == null) {
              throw new IllegalArgumentException("Parameter resourceGroupName is required and cannot be null.");
          }
          if (this.client.subscriptionId() == null) {
              throw new IllegalArgumentException("Parameter this.client.subscriptionId() is required and cannot be null.");
          }
          if (resourceName == null) {
              throw new IllegalArgumentException("Parameter resourceName is required and cannot be null.");
          }
          if (this.client.apiVersion() == null) {
              throw new IllegalArgumentException("Parameter this.client.apiVersion() is required and cannot be null.");
          }
          return service.getDefault(resourceGroupName, this.client.subscriptionId(), resourceName, this.client.apiVersion(), this.client.acceptLanguage(), this.client.userAgent())
              .flatMap(new Func1<Response<ResponseBody>, Observable<ServiceResponse<WorkItemConfigurationInner>>>() {
                  @Override
                  public Observable<ServiceResponse<WorkItemConfigurationInner>> call(Response<ResponseBody> response) {
                      try {
                          ServiceResponse<WorkItemConfigurationInner> result = getDefaultDelegate(response);
                          ServiceResponse<WorkItemConfigurationInner> clientResponse = new ServiceResponse<WorkItemConfigurationInner>(result.body(), result.response());
                          return Observable.just(clientResponse);
                      } catch (Throwable t) {
                          return Observable.error(t);
                      }
                  }
              });
      }
docs: Gets default work item configurations that exist for the application.
  
  @param resourceGroupName The name of the resource group.
  @param resourceName The name of the Application Insights component resource.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the WorkItemConfigurationInner object