类的抽象与封装
package 类的抽象与封装;
import java.util.Scanner;
public class 圆类 {
private double radius;
public double getRadius() {
return radius;
}
public void setRadius(double radius) {
this.radius = radius;
}
//无参构造函数
public void Circle(){
this.radius=0;
}
//带参构造函数
public void Circle(double r ){
this.radius=r;
}
//获取面积
public double getArea(){
double r=this.radius;
double area=r*r*3.14;
return area;
}
//获取周长
public double getPerimeter(){
double perimeter=this.radius*2*3.14;
return perimeter;
}
//打印圆的信息
public void show(){
System.out.println("请输入圆的半径");
Scanner sc=new Scanner(System.in);
this.setRadius(sc.nextInt());
System.out.println("圆的半径"+this.getRadius());
System.out.println("圆的面积"+this.getArea());
System.out.println("圆的周长"+this.getPerimeter());
}
}
//圆柱类
public class Cylinder extends Circle {
//圆柱高
private double height;
public double getHeight() {
return height;
}
public void setHeight(double height) {
this.height = height;
}
//构造方法
public Cylinder (double r, double h){
super();
this.height=h;
this.setRadius(r);
}
public double getVolume( ) {
double volume=this.getArea()*this.height;
return volume;
}
//求体积
public void showVolume(){
System.out.println("圆柱的体积"+this.getVolume());
}
}
//主程序入口
public class Test {
public static void main(String[] args) {
// TODO Auto-generated method stub
Circle circle=new Circle();
circle.show();
Cylinder cylinder=new Cylinder(2.0,8.5);
cylinder.showVolume();
}
}