code: public void registerMultiValueProvider(MultiValueProvider multiValueProvider) {
      String name = multiValueProvider.getName();
      MultiValueProvider oldProvider = multiValues.put(name, multiValueProvider);
      if (oldProvider != null) {
        LOGGER.warn("MultiValueProvider [{}] @{} has been replaced by [{}]!",
          oldProvider,
          multiValueProvider.getName(),
          multiValueProvider);
      }
      notifyReportableObservers(multiValueProvider);
    }
docs: Add a multi value provider to this appmon4j instance.
  {@link de.is24.util.monitoring.MultiValueProvider} instances allow access to multiple numeric
  values (long)
  
  @param multiValueProvider the MultoValueProvider instance to add