package study.javase.test;

abstract class Shape {
    public final double PI = 3.14;
    public Shape() {
        System.out.println("A shape was create.");
    }
    void draw() {
        System.out.println("Draw a shape");
    }
    // abstract method
    abstract double area();
}
//
class Circle extends Shape {
    int xpos;
    int ypos;
    int radius;
    public Circle() {
        super();
    }
    public Circle(int x, int y, int r) {
        super();
        xpos = x;
        ypos = y;
        radius = r;
    }
    public void draw() {
        System.out.println("draw a circle");
    }
    public double area() {
        return PI*radius*radius;
    }
}
//
class Rectangle extends Shape {
    int left;
    int top;
    int width;
    int height;
    public Rectangle() {
        super();
    }
    public Rectangle(int l, int t, int w, int h) {
        super();
        left = l;
        top = t;
        width = w;
        height = h;
    }
    public double area() {
        return width*height;
    }
}


public class Abstract {
    public static void main(String args[]) {
        Shape rec = new Rectangle(0, 0, 40, 30);
        System.out.println(rec.area());
        rec.draw();
        Shape sha = new Circle(120, 130, 50);
        System.out.println(sha.area());
        sha.draw();
    }
}