package 圆;public class circle { private double Radius; public double getRadius(){ return Radius; }; public void setRadius(double r) { Radius= r; } public circle(double r){ Radius=r; } public double getPerimeter(){//底圆周长 return 2 * Math.PI * Radius; } public double getArea(){//面积 return Math.PI *Radius *Radius; }public void show( ){ System.out.println("圆的半径： " +getRadius()); System.out.println("圆的面积： " +getArea()); System.out.println("圆的周长： " +getPerimeter()); } }package 圆;public class yuanzhu extends circle {//圆柱类继承圆类 private double height; public double getheight() { return height; } public void setheight(double h) { height = h; } public yuanzhu(double r,double h){ super(r);//引用父类同名成员变量 height=h; } public double getVolume(){//得到体积 return getArea() * height; } public void showVolume( ){ System.out.println("圆柱体的体积：" +getVolume()); }}package 圆;public class MAIN { public static void main(String[] args) { circle d1 = new circle(2);//半径初始化为3 d1.show( ); yuanzhu d2 =new yuanzhu(3,6);//高初始化为6 d2.showVolume(); }}结果：圆的半径： 3.0圆的面积： 28.274333882308138圆的周长： 18.84955592153876圆柱体的体积：169.64600329384882
转载于:https://www.cnblogs.com/baoyan/p/8922679.html
