Java BigDecimal類

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 1 package demo04; 2  3 import java.math.BigDecimal; 4  5 //double和float類型在運算中很容易丟失精度,造成資料的不準確性,BigDecimal類可以實現浮點數據的高精度運算 6 public class BigDecimalDemo { 7     public static void main(String[] args) { 8         BigDecimal b1 = new BigDecimal("0.09"); 9         BigDecimal b2 = new BigDecimal("0.01");10         11         //加12         BigDecimal add = b1.add(b2);13         System.out.println(add);14         15         //減16         BigDecimal b3 = new BigDecimal("1");17         BigDecimal b4 = new BigDecimal("0.32");18         BigDecimal sub = b3.subtract(b4);19         System.out.println(sub);20         21         //乘22         BigDecimal b5 = new BigDecimal("1.015");23         BigDecimal b6 = new BigDecimal("100");24         BigDecimal mul = b5.multiply(b6);25         System.out.println(mul);26         27         //除 BigDecimal divide(BigDecimal divisor, int scale, int roundingMode) 28         BigDecimal b7 = new BigDecimal("1.301");29         BigDecimal b8 = new BigDecimal("101");30         BigDecimal div = b7.divide(b8,2,BigDecimal.ROUND_UP);        //0.0231         BigDecimal div1 = b7.divide(b8,2,BigDecimal.ROUND_DOWN);     //0.0132         BigDecimal div2 = b7.divide(b8,2,BigDecimal.ROUND_HALF_UP);  //四捨五入33         System.out.println(div);34         System.out.println(div1);35         System.out.println(div2);36     }37 }

 

Java BigDecimal類