code: public Observable<List<MetricsResultsItem>> getMultipleAsync(String appId, List<MetricsPostBodySchema> body) {
          return getMultipleWithServiceResponseAsync(appId, body).map(new Func1<ServiceResponse<List<MetricsResultsItem>>, List<MetricsResultsItem>>() {
              @Override
              public List<MetricsResultsItem> call(ServiceResponse<List<MetricsResultsItem>> response) {
                  return response.body();
              }
          });
      }
docs: Retrieve metric data.
  Gets metric values for multiple metrics.
  
  @param appId ID of the application. This is Application ID from the API Access settings blade in the Azure portal.
  @param body The batched metrics query.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the List&lt;MetricsResultsItem&gt; object