關於String類型，轉換BigDecimal .並且BigDecimal 的乘法計算

//減法計算

BigDecimal insuranceAmt= BigDecimal.ZERO;

BigDecimal price_JQX = BigDecimal.ZERO;

 

BigDecimal price = insuranceAmt.subtract(price_JQX); 

//乘法計算，保留兩位小數,只舍去不入

 BigDecimal price_bonus = price.multiply(new BigDecimal(0.94,new MathContext(2))).setScale(2, BigDecimal.ROUND_DOWN); 

//加法運算

public static double add(double v1, double v2) {
        BigDecimal b1 = new BigDecimal(Double.toString(v1));
        BigDecimal b2 = new BigDecimal(Double.toString(v2));
        return b1.add(b2).doubleValue();
    }

 

//字符串與BigDecimal的相互轉換

BigDecimal b = new BigDecimal(columnValue);
//變成金錢格式,留   .0
DecimalFormat format = new DecimalFormat("0.0");
String floatString = format.format(b);

//String 轉換 BigDecimal

String a = "1.1";  //字符串類型，必須是數字，否則會報錯， java.lang.NumberFormatException 異常

System.out.println(new BigDecimal(a));