docs: private void initializeHistoryEventHandlers(final List<HistoryEventHandler> historyEventHandlers) {
      EnsureUtil.ensureNotNull("History event handler", historyEventHandlers);
      for (HistoryEventHandler historyEventHandler : historyEventHandlers) {
        EnsureUtil.ensureNotNull("History event handler", historyEventHandler);
        this.historyEventHandlers.add(historyEventHandler);
      }
    }