code: public Observable<Page<CsmUsageQuotaInner>> listUsagesNextAsync(final String nextPageLink) {
          return listUsagesNextWithServiceResponseAsync(nextPageLink)
              .map(new Func1<ServiceResponse<Page<CsmUsageQuotaInner>>, Page<CsmUsageQuotaInner>>() {
                  @Override
                  public Page<CsmUsageQuotaInner> call(ServiceResponse<Page<CsmUsageQuotaInner>> response) {
                      return response.body();
                  }
              });
      }
docs: Gets server farm usage information.
  Gets server farm usage information.
  
  @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;CsmUsageQuotaInner&gt; object