code: public static NumberingFormat getNumberingFormat(char formatCode)
    {
      switch(formatCode) {
      case 'n':
        return new ArabicNumeralNumbering();
      case 's':
        return new LowerCaseStringNumbering();
      case 'S':
        return new UpperCaseStringNumbering();
      case 'i':
        return new LowerCaseRomanNumbering();
      case 'I':
        return new UpperCaseRomanNumbering();
      }
      throw new TemplateException("Invalid numbering format code |%s|.", formatCode);
    }
docs: Factory method for numbering format implementations. If format code is not recognized throws templates exception; anyway
  validation tool catches this condition. See {@link NumberingFormat} for the list of valid format codes.
  
  @param formatCode single char format code.
  @return requested numbering format instance.
  @throws TemplateException if format code is not recognized.