将阿拉伯数字转换为中文大写形式（金额模式）

来自豆包，靠谱

import java.math.BigDecimal;
import java.math.RoundingMode;

public class MoneyToChiness {
    private static final String[] CN_UPPER_NUMBER = {"零", "壹", "贰", "叁", "肆", "伍", "陆", "柒", "捌", "玖"};
    private static final String[] CN_UPPER_UNIT = {"", "拾", "佰", "仟"};
    private static final String[] CN_GROUP = {"", "万", "亿"};

    public static String moneyToChinese(BigDecimal i_money) {
        if (i_money.equals(BigDecimal.ZERO)) {
            return "零圆整";
        }
        Double max = 1000000000000D;
        Double min = 0.01D;
        if (i_money.doubleValue() >= max || i_money.doubleValue() < min) {
            return "大于1万亿或小于1分了";
        }
        i_money = i_money.setScale(2, RoundingMode.HALF_UP);
        String numStr = i_money.toString();
        int pointPos = numStr.indexOf('.');
        String s_int = null;
        String s_point = null;
        if (pointPos >= 0) {
            s_int = numStr.substring(0, pointPos);
            s_point = numStr.substring(pointPos + 1);
        } else {
            s_int = numStr;
        }
        StringBuilder sb = new StringBuilder();
        if ("0".equals(s_int)) {
            sb.append("零元整");
        } else {
            int groupCount = (int) Math.ceil(s_int.length() / 4.0);
            for (int group = 0; group < groupCount; group++) {
                boolean zeroFlag = true;
                boolean noZeroFlag = false;
                int start = (s_int.length() % 4 == 0? 0 : (s_int.length() % 4 - 4)) + 4 * group;
                for (int i = 0; i < 4; i++) {
                    if (i + start >= 0) {
                        int value = s_int.charAt(i + start) - '0';
                        if (value > 0) {
                            sb.append(CN_UPPER_NUMBER[value]);
                            if (i < 3) {
                                sb.append(CN_UPPER_UNIT[i]);
                            }
                            zeroFlag = true;
                            noZeroFlag = true;
                        } else if (zeroFlag) {
                            sb.append('零');
                            zeroFlag = false;
                        }
                    }
                }
                if (sb.charAt(sb.length() - 1) == '零') {
                    sb.deleteCharAt(sb.length() - 1);
                }
                if (noZeroFlag || groupCount - group == 1) {
                    sb.append(CN_GROUP[groupCount - group - 1]);
                }
            }
            sb.append('元');
            if (s_point == null || "00".equals(s_point)) {
                sb.append('整');
            } else {
                int j = s_point.charAt(0) - '0';
                int f = s_point.charAt(1) - '0';
                sb.append(CN_UPPER_NUMBER[j]).append('角');
                sb.append(CN_UPPER_NUMBER[f]).append('分');
            }
        }
        return sb.toString();
    }

    public static void main(String[] args) {
        BigDecimal amount = new BigDecimal("1234.56");
        System.out.println(moneyToChinese(amount));
    }
}