code: public Observable<Page<DomainInner>> listAsync() {
          return listWithServiceResponseAsync().map(new Func1<ServiceResponse<List<DomainInner>>, Page<DomainInner>>() {
              @Override
              public Page<DomainInner> call(ServiceResponse<List<DomainInner>> response) {
                  PageImpl<DomainInner> page = new PageImpl<>();
                  page.setItems(response.body());
                  return page;
              }
          });
      }
docs: List domains under an Azure subscription.
  List all the domains under an Azure subscription.
  
  @return the observable to the List&lt;DomainInner&gt; object