code: public MoneyAmountStyle withPositiveSignCharacter(Character positiveCharacter) {
          int positiveVal = (positiveCharacter == null ? -1 : positiveCharacter);
          if (positiveVal == this.positiveCharacter) {
              return this;
          }
          return new MoneyAmountStyle(
                  zeroCharacter,
                  positiveVal, negativeCharacter,
                  decimalPointCharacter, groupingStyle,
                  groupingCharacter, groupingSize, extendedGroupingSize, forceDecimalPoint, absValue);
      }
docs: Returns a copy of this style with the specified positive sign character.
  <p>
  The standard ASCII symbol is '+'.
  
  @param positiveCharacter  the positive character, null if to be determined by locale
  @return the new instance for chaining, never null