code: public static <I extends Request, O extends Response>
      Function<Service<I, O>, MetricCollectingService<I, O>> newDecorator(
              MeterIdPrefixFunction meterIdPrefixFunction) {
  
          requireNonNull(meterIdPrefixFunction, "meterIdPrefixFunction");
          return delegate -> new MetricCollectingService<>(delegate, meterIdPrefixFunction);
      }
docs: Returns a new {@link Service} decorator that tracks request stats using {@link MeterRegistry}.