code: public void registerStateValue(StateValueProvider stateValueProvider) {
      String name = keyHandler.handle(stateValueProvider.getName());
      StateValueProvider oldProvider = stateValues.put(name, stateValueProvider);
      if (oldProvider != null) {
        LOGGER.warn("StateValueProvider [{}] @{} has been replaced by [{}]!",
          oldProvider,
          stateValueProvider.getName(),
          stateValueProvider);
      }
      notifyReportableObservers(stateValueProvider);
    }
docs: Add a state value provider to this appmon4j instance.
  {@link de.is24.util.monitoring.StateValueProvider} instances allow access to a numeric
  value (long), that is already available in the application.
  
  @param stateValueProvider the StateValueProvider instance to add