code: public ServiceFuture<SubscriptionUsageInner> getAsync(String locationName, String usageName, final ServiceCallback<SubscriptionUsageInner> serviceCallback) {
          return ServiceFuture.fromResponse(getWithServiceResponseAsync(locationName, usageName), serviceCallback);
      }
docs: Gets a subscription usage metric.
  
  @param locationName The name of the region where the resource is located.
  @param usageName Name of usage metric to return.
  @param serviceCallback the async ServiceCallback to handle successful and failed responses.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceFuture} object