Facade Design Pattern

Facade design pattern is used when there is a set of interfaces to be used for the client. What we can do is create a single interface, that incorporates all the capabilities of all the interfaces, for the client. Using this interface, the client can interact with the system. This single interface works as a facade for the entire system. It reduces the system's complexity, making it easier for the client. 

BoxOffice interface

package com.sks.facade;

public interface BoxOfficeI {
	
	public void bookTickets();

}

FoodCounter interface

package com.sks.facade;

public interface FoodCounterI {

	public void buyFood();
	
}

ToysCounter interface

package com.sks.facade;

public interface ToysCounterI {
	
	void buyToys();

}

BoxOffice implementation

package com.sks.facade;

public class BoxOffice implements BoxOfficeI {
	
	public void bookTickets() {
		System.out.println("Your tickets have been booked.");
	}
	
}

FoodCounter implementation

package com.sks.facade;

public class FoodCounter implements FoodCounterI {

	public void buyFood() {
		System.out.println("Food purchase successful. Please pay at the counter.");
	}
	
}

ToysCounter implementation

package com.sks.facade;

public class ToysCounter implements ToysCounterI {
	
	public void buyToys() {
		System.out.println("Toy purchase successful. Please pay.");
	}

}

Facade interface

package com.sks.facade;

public interface BookMyMovieKioskI {
	
	public void justWatchAMovie();
	public void enjoySomeFood();
	public void buySomeToys();
}

Facade implmentation

package com.sks.facade;

public class BookMyMovieKiosk {
	
	private BoxOfficeI boxOffice;
	private FoodCounterI foodCounter;
	private ToysCounterI toysCounter;
	
	public void justWatchAMovie() {
		boxOffice.bookTickets();
	}
	
	public void enjoyMovieWithSomeFood() {
		boxOffice.bookTickets();
		foodCounter.buyFood();
	}
	
	public void enjoyMovieWithFoodAndbuyToys() {
		enjoyMovieWithSomeFood();
		toysCounter.buyToys();
	}
	

	public BookMyMovieKiosk(BoxOfficeI boxOffice, FoodCounterI foodCounter, ToysCounterI toysCounter) {
		super();
		this.boxOffice = boxOffice;
		this.foodCounter = foodCounter;
		this.toysCounter = toysCounter;
	}

}

Facade pattern test class

package com.sks.facade;

public class BookMyMovieKiosk {
	
	private BoxOfficeI boxOffice;
	private FoodCounterI foodCounter;
	private ToysCounterI toysCounter;
	
	public void justWatchAMovie() {
		boxOffice.bookTickets();
	}
	
	public void enjoyMovieWithSomeFood() {
		boxOffice.bookTickets();
		foodCounter.buyFood();
	}
	
	public void enjoyMovieWithFoodAndbuyToys() {
		enjoyMovieWithSomeFood();
		toysCounter.buyToys();
	}
	

	public BookMyMovieKiosk(BoxOfficeI boxOffice, FoodCounterI foodCounter, ToysCounterI toysCounter) {
		super();
		this.boxOffice = boxOffice;
		this.foodCounter = foodCounter;
		this.toysCounter = toysCounter;
	}
}

Output :