Burger Restaurant

This project implements a small burger restaurant where a young boy, who has completed a course for chefs, decides to open his own business. The restaurant operates with a chef and a cashier, and offers three types of burgers: royal, classic, and vegetarian. Additionally, various sauces can be added to the burgers.

Design Patterns Used

1. Singleton - Restaurant

The Singleton design pattern is used to ensure that there is only one instance of the Restaurant class throughout the application. This allows easy access to the restaurant instance from different parts of the code.

2. Command - Cashier and Chef

The Command design pattern is used to implement the interaction between the Cashier and Chef classes. The Cashier acts as the invoker, taking orders and encapsulating them as commands to be executed by the Chef. The Chef is the receiver, responsible for executing the commands and preparing the requested burgers.

3. Factory - Kitchen and Burgers

The Factory design pattern is used to create different types of burgers in the Kitchen. The Kitchen serves as the factory, providing an interface to create the burgers (RoyalBurger, ClassicBurger, and VegetarianBurger).

4. Decorator - Add sauces to the burger

The Decorator design pattern is used to add sauces to the burgers. The Burger class serves as the base component, and the GarlicSauce and Ketchup classes act as decorators that can be added to the burgers to enhance their flavor.

Class Diagram

                    +------------------+
                    |    Restaurant    |
                    +------------------+
                    | - chef: Chef     |
                    | - cashier: Cashier |
                    +------------------+
                               |
                               |
                 +-----------------------------+
                 |           Cashier           |
                 +-----------------------------+
                 | - orderQueue: Queue<Command> |
                 |                             |
                 | +takeOrder(order: Order): void |
                 | +placeOrder(): void           |
                 +-----------------------------+
                               |
                               |
                 +-----------------------------+
                 |             Chef            |
                 +-----------------------------+
                 | - kitchen: Kitchen           |
                 |                             |
                 | +setKitchen(kitchen: Kitchen): void |
                 | +cookBurger(burger: Burger): void  |
                 +-----------------------------+
                               |
                               |
                 +-----------------------------+
                 |           Kitchen           |
                 +-----------------------------+
                 | +createBurger(type: String): Burger |
                 +-----------------------------+
                 |        ^ (implements)        |
                 |                             |
                 |       BurgerFactory         |
                 +-----------------------------+
                               |
                   +---------+---------+
                   |                   |
           +--------------+     +----------------+
           | RoyalBurger  |     | ClassicBurger  |
           +--------------+     +----------------+
                               |
                   +---------+---------+
                   |                   |
             +--------------------+
             | VegetarianBurger  |
             +--------------------+
                               |
                   +---------+---------+
                   |                   |
          +-----------------+   +----------------+
          |    Burger       |   |    Sauce       |
          +-----------------+   +----------------+
                   |                   |
                   |             +---------------+
                   |             |  GarlicSauce  |
                   |             +---------------+
                   |                   |
                   |             +-----------+
                   |             |   Ketchup   |
                   |             +-----------+
                   |                   
                   |

Please note that the class diagram is a simplified representation of the design. Actual implementation details and method signatures are omitted for brevity.