code: public Observable<ContainerServiceInner> getByResourceGroupAsync(String resourceGroupName, String containerServiceName) {
          return getByResourceGroupWithServiceResponseAsync(resourceGroupName, containerServiceName).map(new Func1<ServiceResponse<ContainerServiceInner>, ContainerServiceInner>() {
              @Override
              public ContainerServiceInner call(ServiceResponse<ContainerServiceInner> response) {
                  return response.body();
              }
          });
      }
docs: Gets the properties of the specified container service.
  Gets the properties of the specified container service in the specified subscription and resource group. The operation returns the properties including state, orchestrator, number of masters and agents, and FQDNs of masters and agents.
  
  @param resourceGroupName The name of the resource group.
  @param containerServiceName The name of the container service in the specified subscription and resource group.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the ContainerServiceInner object