Circle类:
import java.math.BigDecimal;
public class Circle {
private BigDecimal r;
public Circle() {
}
public Circle(BigDecimal r) {
super();
this.r = r;
}
public BigDecimal getR() {
return r;
}
public void setR(BigDecimal r) {
this.r = r;
}
public BigDecimal getArea() {
return this.getR().pow(2).multiply(new BigDecimal(Math.PI)).setScale(2, BigDecimal.ROUND_HALF_UP);
}
public BigDecimal getPerimeter() {
return this.getR().multiply(new BigDecimal(2)).multiply(new BigDecimal(Math.PI)).setScale(2,
BigDecimal.ROUND_HALF_UP);
}
}
测试类:
public class App {
public static void main(String[] args) {
BigDecimal r = new BigDecimal(3.12);
Circle c = new Circle(r);
System.out.println("圆面积为===>" + c.getArea());
System.out.println("圆周长为===>" + c.getPerimeter());
}
}
结果:
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/b3b7d0a20cf431ad9f9466514536acaf2edd9817?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
拿走不谢