Non-terminating decimal expansion; no exact representable decimal res

    /**
     * a / b   计算百分比
     * @param a
     * @param b
     * @return eg:65.32
     */
    public static String ADivideB(BigDecimal a,BigDecimal b){
        String result =
                b == null ? "-" :
                        a == null ? "0.00" :
                                a.divide(b,4).setScale(2,BigDecimal.ROUND_HALF_UP) + "";
        return result;
    }