package com.imooc.measurable;

public interface Measurable {
    double getArea();
    double getPerimeter();
}


package com.imooc.measurable;

abstract class Shape implements Measurable {
    protected String name;

    public Shape(String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }

    public abstract double getArea();

    public abstract double getPerimeter();
}


package com.imooc.measurable;

class Circle extends Shape {
    private double radius;

    public Circle(double radius) {
        super("Circle");
        this.radius = radius;
    }

    @Override
    public double getArea() {
        return Math.PI * radius * radius;
    }

    @Override
    public double getPerimeter() {
        return 2 * Math.PI * radius;
    }
}

package com.imooc.measurable;

class Rectangle extends Shape {
    private double length;
    private double width;

    public Rectangle(double length, double width) {
        super("Rectangle");
        this.length = length;
        this.width = width;
    }

    @Override
    public double getArea() {
        return length * width;
    }

    @Override
    public double getPerimeter() {
        return 2 * (length + width);
    }
}


package com.imooc.measurable;

public class TestShapes {
    public static void main(String[] args) {
        Circle circle = new Circle(5);
        Rectangle rectangle = new Rectangle(4, 6);

        System.out.println(circle.getName() + " 的面积为: " + circle.getArea());
        System.out.println(circle.getName() + " 的周长为: " + circle.getPerimeter());

        System.out.println(rectangle.getName() + " 的面积为: " + rectangle.getArea());
        System.out.println(rectangle.getName() + " 的周长为: " + rectangle.getPerimeter());
    }
}