private char nonZeroDigitToken(PositionTrackingPushbackReader par1PositionTrackingPushbackReader) throws IOException, InvalidSyntaxException
    {
        char c1 = (char)par1PositionTrackingPushbackReader.read();
        char c;

        switch (c1)
        {
            case 49:
            case 50:
            case 51:
            case 52:
            case 53:
            case 54:
            case 55:
            case 56:
            case 57:
                c = c1;
                break;

            default:
                throw new InvalidSyntaxException((new StringBuilder()).append("Expected a digit 1 - 9 but got [").append(c1).append("].").toString(), par1PositionTrackingPushbackReader);
        }

        return c;
    }