How to use polymorphism to make list with different types in java?

Question

I have 3 Classes Circle, Rectangle and Square

I want to get required data for each of above classes and create them by user .

It me

Answer 1

Create a interface lets call TwoDimensionalShape and put common methods in it.

public interface TwoDimensionalShape {
   double calculateArea();
   int calculatePrimeter();
}

And all the classes implement this interface

public class Circle implements TwoDimensionalShape {
    //your code 
}

public class Rectangle implements TwoDimensionalShape {
    //your code 
}

public class Square implements TwoDimensionalShape {
    //your code 
}

And create a List and put all these shapes in this list. Like

List shapes= new ArrayList();
shapes.add(new Circle(5));
shapes.add(new Rectangle(4,3));
shapes.add(new Square(4));
for (TwoDimensionalShape shape : shapes) {
    System.out.println("Area = " + shape.calculateArea());
    System.out.println("Perimeter = " + shape.calculatePrimeter());
}