docs: public MoneyAmountStyle withGroupingCharacter(Character groupingCharacter) {
          int groupingVal = (groupingCharacter == null ? -1 : groupingCharacter);
          if (groupingVal == this.groupingCharacter) {
              return this;
          }
          return new MoneyAmountStyle(
                  zeroCharacter,
                  positiveCharacter, negativeCharacter,
                  decimalPointCharacter, groupingStyle,
                  groupingVal, groupingSize, extendedGroupingSize, forceDecimalPoint, absValue);
      }