import java.math.BigDecimal;
import java.math.RoundingMode;
import java.text.DecimalFormat;



public final class AmountUtil {
    private static DecimalFormat LIMIT_AMOUNT_FORMAT = new DecimalFormat("#.00");

    static {
        LIMIT_AMOUNT_FORMAT.setRoundingMode(RoundingMode.FLOOR);
    }

    /**
 

     * 1億
     */
    private static final int HUNDRED_MILLION = 100000000;

    /**
     * 1萬
     */
    private static final int TEN_THOUSAND = 10000;

    /**
     * 金額轉換為自定義字符串(保留兩位小數)
     */
    public static String CustomFormatWith2Digits(int amount) {
        if (0 < amount && amount < TEN_THOUSAND) {
            
 
return String.format("%d元", amount);
        } else if (TEN_THOUSAND <= amount  && amount < HUNDRED_MILLION) {
            if (amount % TEN_THOUSAND == 0) {
                return String.format("%d萬元", amount / TEN_THOUSAND);
            } else {
                BigDecimal tmpAmount = BigDecimal.valueOf(amount * 1.0 / TEN_THOUSAND);
                
 
return String.format("%s萬元", LIMIT_AMOUNT_FORMAT.format(tmpAmount));
            }
        } else if (HUNDRED_MILLION <= amount) {
            if (amount % HUNDRED_MILLION == 0) {
                return String.format("%d億元", amount / HUNDRED_MILLION);
            } else {
                BigDecimal tmpAmount = BigDecimal.valueOf(amount * 1.0 / HUNDRED_MILLION);
                return String.format("%s億元", LIMIT_AMOUNT_FORMAT.format(tmpAmount));
            }
        }
        return "";
    }

    /**
     * 金額字符串(可能帶千分位)轉換為自定義字符串(保留兩位小數)
     */
    public static String CustomFormatWith2Digits(String amountStr) {
        int amount = 0;
        try {
            if (amountStr.contains(",")) {
                amountStr = amountStr.replace(",", "");
            }
            amount = Integer.parseInt(amountStr);
        } catch (NumberFormatException e) {
            return "";
        }

        return CustomFormatWith2Digits(amount);
    }
}

金額轉換為自定義字符串