code: public Observable<Page<NetworkInterfaceIPConfigurationInner>> listAsync(final String resourceGroupName, final String networkInterfaceName) {
          return listWithServiceResponseAsync(resourceGroupName, networkInterfaceName)
              .map(new Func1<ServiceResponse<Page<NetworkInterfaceIPConfigurationInner>>, Page<NetworkInterfaceIPConfigurationInner>>() {
                  @Override
                  public Page<NetworkInterfaceIPConfigurationInner> call(ServiceResponse<Page<NetworkInterfaceIPConfigurationInner>> response) {
                      return response.body();
                  }
              });
      }
docs: Get all ip configurations in a network interface.
  
  @param resourceGroupName The name of the resource group.
  @param networkInterfaceName The name of the network interface.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the PagedList&lt;NetworkInterfaceIPConfigurationInner&gt; object