code: public ServiceFuture<VirtualHubInner> createOrUpdateAsync(String resourceGroupName, String virtualHubName, VirtualHubInner virtualHubParameters, final ServiceCallback<VirtualHubInner> serviceCallback) {
          return ServiceFuture.fromResponse(createOrUpdateWithServiceResponseAsync(resourceGroupName, virtualHubName, virtualHubParameters), serviceCallback);
      }
docs: Creates a VirtualHub resource if it doesn't exist else updates the existing VirtualHub.
  
  @param resourceGroupName The resource group name of the VirtualHub.
  @param virtualHubName The name of the VirtualHub.
  @param virtualHubParameters Parameters supplied to create or update VirtualHub.
  @param serviceCallback the async ServiceCallback to handle successful and failed responses.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceFuture} object