小数点后不给出结果的大数

Question

I have the following method to calculation percentage

    public static BigDecimal getPercentageSave(BigDecimal totalCostAfterSale, BigDecimal totalCostBeforeSale) {
        BigDecimal save = totalCostBeforeSale.subtract(totalCostAfterSale);
        if (save.compareTo(BigDecimal.ZERO) == 0) {
            return BigDecimal.ZERO;
        }
        return (save.divide(totalCostBeforeSale, 2, RoundingMode.DOWN)).multiply(new BigDecimal(100));
    }

But it only gives me results like xx.00 Eg. 56.00, 78.00

How can i get the something like 56.21 or 78.01

Answer 1

您的错误是在乘以100之前先进行四舍五入。相反，您可以先乘以100，然后在乘以后以2的精度进行除法，如下所示：

return (save.multiply(new BigDecimal(100)).divide(totalCostBeforeSale, 2, RoundingMode.DOWN));