docs: public static void register(MetricsRegistry metricsRegistry) {
          checkNotNull(metricsRegistry, "metricsRegistry");
  
          ClassLoadingMXBean mxBean = ManagementFactory.getClassLoadingMXBean();
  
          metricsRegistry.register(mxBean, "classloading.loadedClassesCount", MANDATORY, ClassLoadingMXBean::getLoadedClassCount);
  
          metricsRegistry.register(mxBean, "classloading.totalLoadedClassesCount", MANDATORY,
                  ClassLoadingMXBean::getTotalLoadedClassCount);
  
          metricsRegistry.register(mxBean, "classloading.unloadedClassCount", MANDATORY, ClassLoadingMXBean::getUnloadedClassCount);
      }