Java NOOP(Non-Object Oriented) Demo

Main.java

public class Main {
    public static void main(String[] args) {
        Shapes s = new Shapes();

        s.calculateCircleArea(5.0);

        s.displayArea();
        s.displayFormattedArea();

        System.out.println(); // spacing

        s.calculateRectangleArea(10, 10);

        s.displayArea();
        s.displayFormattedArea();
    }
}

Shapes.java

public class Shapes {

    double result = 0.0; // Holds our result

    public Shapes() {}

    public double calculateCircleArea(double radius)
    {
        // Math.PI is a static property - can be accessed anywhere in your program
        // without instantiating a class/creating on object of a class.
        result = Math.PI * radius * radius;

        return result;
    }

    public double calculateRectangleArea(double length, double width)
    {
        result = length * width;

        return result;
    }

    // Continue with the rest of the Shapes here
    // ..........................................



    public void displayArea()
    {
        System.out.println("The area of the shape is: " + result + " square meters");
    }

    public void displayFormattedArea()
    {
        // A formatted output for readability
        // %.2f means print to 2 decimal places. f- decimal e.g. %f, d - integer e.g. %d, s - string e.g. %s
        // %n - means move cursor to a new line
        System.out.printf("The area of the shape is: %.2f square meters%n ", result);
    }
}