Inheritance enables you to define a general class (i.e., a superclass) and later extend it to more specialized classes (i.e., subclasses).

Superclass Definition

public class Geometry{

    private String color = "white";

        public Geometry(){

    }

    public Geometry(String color){

        this.color = color;

    }

    public void setColor(String color){

        this.color = color;

    }

    public String getColor(){

        return this.color;

    }

    @Override

    public String toString(){

        return "This is a " + color + " geometry";

    }

}

Subclasses Definition Using extends

public class Circle extends Geometry{

    private double radius = 1.0;

}

public class Rectangle extends Geometry{

    private double width = 1.0;

    private double height = 1.0;

}