package balloonInherit;
 
public class superBalloon
{
	/**
	 * The superBalloon class defines methods and variables common to all balloons such as
	 * size, color and price
	 */
	//commonly used fields in all balloons
	public int size;
        public String color;
	public double price;
	public int number_of_balloons_purchased;
	public double total_cost;
 
	public void purchase(double price, int number_of_balloons_purchased)
	{
		total_cost = (price * number_of_balloons_purchased);
	}
}

package balloonInherit;
 
public class subPartyBalloon extends superBalloon
{
	/**
	 * Since this is a partyBalloon, an additional new field called decoration cost is added
	 * which is specific to this kind of balloon
	 */
 
	public static void main(String args[])
	{
		//Create an object for subPartyBalloon class and invoke the purchase method
                subPartyBalloon bDayBalloon = new subPartyBalloon();
		bDayBalloon.purchase();
	}
 
	public void purchase()
	{
		//Additional property specific to the type partyBalloon
		double decoration_cost = 2.00;
 
		//Reuse the existing properties of the base class using super keyword
		super.size = 20;
		super.number_of_balloons_purchased = 3;
		super.color = "red";
 
		//These are the prices of the balloon depending on it's size
		switch (super.size)
		{
			case 10:
				super.price = 5.00;
				break;
			case 20:
				super.price = 10.00;
				break;
			case 30:
				super.price = 15.00;
				break;
			default:
				System.out.println("Invalid size");
		}
 
		//Invoke the the purchase methods of the super class to calculate the base_cost
		super.purchase(price,number_of_balloons_purchased);
 
		//Since it is a birthday party balloon the additional cost for decoration is added
		total_cost = total_cost + decoration_cost;
 
		System.out.format("The total cost of %d %s birthday balloons is %.2f", number_of_balloons_purchased,color,total_cost);
	}
}

package balloonInherit;
 
public class subThemeBalloon extends superBalloon
{
	/**
	 * A theme based balloon has theme and design as additional fields. For example to represent
	 * the theme of Disneyland a balloon is designed with the theme Disneyland and with
	 * the shape mickey mouse
	 **/
 
	public static void main(String[] args)
	{
                //Create an object of subThemeBalloon class and invoke the purchase method
                subThemeBalloon themeBalloon = new subThemeBalloon();
		themeBalloon.purchase();
	}
 
	public void purchase()
	{
		//Declare three additional properties that are specific to the type themeBalloon
		String theme = "Disneyland";
		String design = "Mickey Mouse";
		int decoration_cost = 5;
 
		//Reuse the existing properties of the base class using super keyword
		super.number_of_balloons_purchased = 20;
		super.price = 15.00;
 
		//Invoke the purchase method of the base balloon class to calculate base cost using super keyword
		super.purchase(price, number_of_balloons_purchased);
 
		//Add the decoration cost for the balloon
		total_cost = total_cost + decoration_cost;
 
		//Print the total cost of the balloon
		System.out.format("The total cost of a %s %s balloon is %.2f", theme, design, total_cost);
	}
}