Java --人民币(RMB)小写/数字转换大写工具类

 人民币(RMB)小写/数字转换大写工具类，精确到分，修复‘圆零零’为‘圆整’，修复科学计数法处理异常。

    /**
     * 转换为中国人民币大写字符串,精确到分
     * @param money 传入小写数字字符串
     * @return String
     * @throws Exception
     */
    public static String toRMBUpper(String money) throws Exception {
        boolean lessZero = false;
        //When money is scientific notation
        if (money.contains("E")){
            BigDecimal bg = new BigDecimal(Double.valueOf(money));
            money = bg.toPlainString();
        }
        if(money.startsWith("-")) {
            money = money.substring(1);
            lessZero = true;
        }

        if (!money.matches("^[0-9]*$|^0+\\.[0-9]+$|^[1-9]+[0-9]*$|^[1-9]+[0-9]*.[0-9]+$")) {
            throw new Exception("钱数格式错误！");
        }
        String[] part = money.split("\\.");
        String integerData = part[0];
        String decimalData = part.length > 1 ? part[1] : "";
        //Replace front 0
        if(integerData.matches("^0+$"))
        {
            integerData = "0";
        }else if(integerData.matches("^0+(\\d+)$")){
            integerData = integerData.replaceAll("^0+(\\d+)$", "$1");
        }

        StringBuffer integer = new StringBuffer();
        for (int i = 0; i < integerData.length(); i++) {
            char perchar = integerData.charAt(i);
            integer.append(upperNumber(perchar));
            integer.append(upperNumber(integerData.length() - i - 1));
        }
        StringBuffer decimal = new StringBuffer();
        if (part.length > 1 && !"00".equals(decimalData)) {
            int length = decimalData.length() >= 2 ? 2 : decimalData.length();
            for (int i = 0; i < length; i++) {
                char perchar = decimalData.charAt(i);
                decimal.append(upperNumber(perchar));
                if (i == 0)
                    decimal.append('角');
                if (i == 1)
                    decimal.append('分');
            }
        }
        String result = integer.toString() + decimal.toString();
        result = dispose(result);
        if(lessZero && !"零圆整".equals(result)) {
            result = "负" + result;
        }
        return result;
    }

    private static char upperNumber(char number) {
        switch (number) {
            case '0':
                return '零';
            case '1':
                return '壹';
            case '2':
                return '贰';
            case '3':
                return '叁';
            case '4':
                return '肆';
            case '5':
                return '伍';
            case '6':
                return '陆';
            case '7':
                return '柒';
            case '8':
                return '捌';
            case '9':
                return '玖';
        }
        return '0';
    }

    private static char upperNumber(int index) {
        int realIndex =  index  % 9;
        if(index > 8) {
            realIndex =  (index - 9) % 8;
            realIndex = realIndex + 1;
        }
        switch (realIndex) {
            case 0:
                return '圆';
            case 1:
                return '拾';
            case 2:
                return '佰';
            case 3:
                return '仟';
            case 4:
                return '万';
            case 5:
                return '拾';
            case 6:
                return '佰';
            case 7:
                return '仟';
            case 8:
                return '亿';
        }
        return '0';
    }

    private static String dispose(String result) {
        result = result.replaceAll("0", "");
        result = result.replaceAll("零仟零佰零拾|零仟零佰|零佰零拾|零仟|零佰|零拾", "零");
        result = result.replaceAll("零+", "零").replace("零亿", "亿");
        result = result.matches("^.*亿零万[^零]仟.*$") ? result.replace("零万", "零") : result.replace("零万", "万");
        result = result.replace("亿万", "亿");
        //Processing decimals
        result = result.replace("零角", "零").replace("零分", "");
        result = result.replaceAll("(^[零圆]*)(.+$)", "$2");
        result = result.replaceAll("(^.*)([零]+圆)(.+$)", "$1圆零$3");

        //Processing integer
        result = result.replaceAll("圆零角零分|圆零角$|圆$|^零$|圆零$|圆零零$|零圆$", "圆整");
        result = result.replaceAll("^圆整$", "零圆整");


        return result;
    }


    public static void main(String[] args) throws Exception {
        //Test
        System.out.println(toRMBUpper("9999999999.0"));
        //Out: 玖拾玖亿玖仟玖佰玖拾玖万玖仟玖佰玖拾玖圆整
    }