code: NewYearRule rule(
          HistoricEra era,
          int yearOfDisplay
      ) {
  
          int ad = era.annoDomini(yearOfDisplay);
          int previous = Integer.MIN_VALUE;
          NewYearRule prevRule = null;
  
          for (int i = 0, n = this.strategies.size(); i < n; i++) {
              NewYearStrategy strategy = this.strategies.get(i);
              if ((ad >= previous) && (ad < strategy.lastAnnoDomini)) {
                  return strategy.lastRule;
              }
              previous = strategy.lastAnnoDomini;
              prevRule = strategy.lastRule;
          }
  
          if ((ad == previous) && (era == HistoricEra.BYZANTINE) && (prevRule == NewYearRule.BEGIN_OF_SEPTEMBER)) {
              return prevRule; // see Russia in byzantine year 7208
          }
  
          return this.lastRule;
  
      }
docs: <p>Determines the appropriate rule for New Year. </p>
  
  @param   era             historic era
  @param   yearOfDisplay   historic year of era as displayed (deviating from standard calendar year)
  @return  NewYearRule
  @since   3.17/4.14