编写一个接口ShapePara，要求： 接口中的方法： int getArea()：获得图形的面积。int getCircumference()：获得图形的周长 编写一个圆类Circle，

Posted 2020-08-09 刁兆建

package com.hanqi.test;
//创建接口
public interface ShapePara {
    
    //获取面积的方法
    double getArea();
    
    //获取周长的方法
    
    double getCircumference();
    

}

package com.hanqi.test;

public class Circle implements ShapePara {
    //定义圆心
    public double radius;
    //定义圆心的横向坐标
    private double X;
    //定义圆心的纵向坐标
    protected double Y;

    public double getX() {
        return X;
    }

    public void setX(double x) {
        X = x;
    }

    public double getY() {
        return Y;
    }

    public void setY(double y) {
        Y = y;
    }
//完善接口的方法
    @Override
    public double getArea() {
        
        return Math.PI*Math.pow(radius, 2);
    }

    @Override
    public double getCircumference() {
        
        return 2*Math.PI*radius;
    }
    
    public Circle(double radius)
    {
        this.radius=radius;
    }
    public double getRadius()
    {
        return radius;
    }
    public void setCenter(double x, double y)
    {
        
        
    }
    public void setRadius(double radius)
    {
        
    }
    

}

package com.hanqi.test;

public class Shape {
    public void getArea()
    {
        
    }

}

package com.hanqi.test;

public class Rect extends Shape {
    private double a;
    
    private double b;

    public double getA() {
        return a;
    }

    public void setA(double a) {
        this.a = a;
    }

    public double getB() {
        return b;
    }

    public void setB(double b) {
        this.b = b;
    }
    //对父类方法进行重写
    public void getArea()
    {
        System.out.println("矩形的长a="+a+",b="+b+"的矩形的面积是："+a*b);
        
    }
    

}

package com.hanqi.test;

public class Test02 {

    public static void main(String[] args) {
        Rect re=new Rect();
        re.setA(20);
        re.setB(30);
        re.getArea();
        
        Circle cc=new Circle(30);
        
        System.out.println("radius=30圆 的面积是："+cc.getArea());

    }

}