code: public Observable<Page<AppServicePlanInner>> listAppServicePlansNextAsync(final String nextPageLink) {
          return listAppServicePlansNextWithServiceResponseAsync(nextPageLink)
              .map(new Func1<ServiceResponse<Page<AppServicePlanInner>>, Page<AppServicePlanInner>>() {
                  @Override
                  public Page<AppServicePlanInner> call(ServiceResponse<Page<AppServicePlanInner>> response) {
                      return response.body();
                  }
              });
      }
docs: Get all App Service plans in an App Service Environment.
  Get all App Service plans in an App Service Environment.
  
  @param nextPageLink The NextLink from the previous successful call to List operation.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the PagedList&lt;AppServicePlanInner&gt; object