繼承練習-形狀(圓形繼承橢圓、橢圓繼承圓形、都不繼承或著...)

Shape.java：

public interface Shape {

public double area();

public void display();
}


RoundShape.java：

public class RoundShape implements Shape {

private int radius1;

private int radius2;

public RoundShape(int radius1,int radius2) {
this.radius1 = radius1;
this.radius2 = radius2;
}

@Override
public double area() {
return radius1 * radius2 * 3.14;
}

@Override
public void display() {
System.out.println("draw and display...");
}
}

Circle.java：

public class Circle extends RoundShape {

public Circle(int radius) {
super(radius, radius);
}
}

Ellipse.java：

public class Ellipse extends RoundShape {

public Ellipse(int radius1, int radius2) {
super(radius1, radius2);
}
}

UserTest.java：

public class UserTest {
public static void main(String[] args) {
Circle circle = new Circle(10);
System.out.println(circle.area());

Ellipse ellipse = new Ellipse(5,10);
System.out.println(ellipse.area());
}
}