code: private <T extends Annotation> boolean checkReusable(MetricResolver.Of<T> of) {
          String name = of.metadata().getName();
          // If the metric has been registered before (eg. metrics found in RequestScoped beans),
          // we don't need to worry about re-usable
          if (!of.isInitialDiscovery()) {
              return true;
          }
  
          Metadata existingMetadata = registry.getMetadata().get(name);
          if (existingMetadata != null && (existingMetadata.isReusable() == false || of.metadata().isReusable() == false)) {
              throw new IllegalArgumentException("Cannot reuse metric for " + of.metricName());
          }
          return true;
  
      }
docs: Checks whether the metric should be re-usable