java中計算百分比保留兩位小數

public class CalculateUtil {
    /**
     * @param a 單數  32
     * @param b 總數  145
     * a / b    計算百分比32/145
     * @return 22.07%
     */
    public static String CalculateUtil(BigDecimal a, BigDecimal b){
        String percent =
                b == null ? "-" :
                        b.compareTo(new BigDecimal(0)) == 0 ? "-":
                                a == null ? "0.00%" :
             a.multiply(new BigDecimal(100)).divide(b,2,BigDecimal.ROUND_HALF_UP) + "%";
        return percent;
    }
 
}