code: public ServiceFuture<List<CsmUsageQuotaInner>> listUsagesAsync(final String resourceGroupName, final String name, final String filter, final ListOperationCallback<CsmUsageQuotaInner> serviceCallback) {
          return AzureServiceFuture.fromPageResponse(
              listUsagesSinglePageAsync(resourceGroupName, name, filter),
              new Func1<String, Observable<ServiceResponse<Page<CsmUsageQuotaInner>>>>() {
                  @Override
                  public Observable<ServiceResponse<Page<CsmUsageQuotaInner>>> call(String nextPageLink) {
                      return listUsagesNextSinglePageAsync(nextPageLink);
                  }
              },
              serviceCallback);
      }
docs: Gets server farm usage information.
  Gets server farm usage information.
  
  @param resourceGroupName Name of the resource group to which the resource belongs.
  @param name Name of App Service Plan
  @param filter Return only usages/metrics specified in the filter. Filter conforms to odata syntax. Example: $filter=(name.value eq 'Metric1' or name.value eq 'Metric2').
  @param serviceCallback the async ServiceCallback to handle successful and failed responses.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceFuture} object