code: protected boolean isEqual(GregorianTimezoneRule rule) {
  
          return (
              this.getTimeOfDay().equals(rule.getTimeOfDay())
              && (this.getDayOverflow() == rule.getDayOverflow())
              && (this.getIndicator() == rule.getIndicator())
              && (this.getSavings() == rule.getSavings())
              && (this.month == rule.month));
  
      }
docs: für Subklassen