alfredlim16/restaurant-management-system

1. This is a Java desktop application for restaurant operations, not a web service. The main runtime is a Swing UI, with role-based entry points for login, cashier work, and manager/admin work.

2. The top-level launch path appears to be restaurantmanagementsystem/RestaurantManagementSystem.java, which likely boots the app and opens the login screen. From there, access is routed by role into user/LoginFrame, cashier/CashierFrame, or manager/ManagerFrame.

3. The architecture is split into three major functional areas:

- user: authentication, authorization, database connection, and shared exception types

- cashier: order taking, payment processing, and receipt generation

- manager: inventory, menu ingredients, food waste, reports, and user management

4. The user package is the shared infrastructure layer. It contains DatabaseConnection, AuthenticationService, PermissionService, AbstractAppService, user/domain objects, and interfaces such as IAuthentication, IPermission, and IUser. This layer enforces access control and provides the database access foundation used by the other modules.

5. The cashier subsystem centers on customer transaction flow. OrdersPanel and PaymentsPanel are the UI surfaces, while OrderService and PaymentService handle the business logic. Domain objects like Order, OrderItem, MenuItem, and Payment are paired with persistence mappers prefixed with Db* such as DbOrder, DbPayment, and DbMenuItem.

6. Cashier data flow is likely: select menu items -> build an Order -> validate status and inventory rules -> create a Payment using a PaymentMethod -> update OrderStatus and PaymentStatus -> display or print a receipt via ReceiptDialog. Failures are surfaced through business exceptions such as PaymentFailedException and InsufficientInventoryException.

7. The manager subsystem supports operational control and reporting. InventoryPanel, MenuItemPanel, FoodWastePanel, ReportsPanel, and UserManagementPanel are the primary screens. Services such as InventoryService, MenuItemService, FoodWasteService, ReportService, and UserManagementService implement the domain workflows behind those screens.

8. Manager data is structured around inventory and menu composition. InventoryItem, MenuItemIngredient, and FoodWaste represent the core entities, with corresponding DB-backed classes like DbInventoryItem, DbMenuItemIngredient, and DbFoodWaste. The presence of IngredientDialog and DatePickerDialog suggests interactive data-entry and filtering for operational updates and reporting.

9. Reports are likely derived from persisted transactional and operational data, not computed entirely in memory. ReportService probably aggregates orders/payments, inventory changes, and food waste into manager-facing summaries shown in ReportsPanel and DashboardPanel.

10. The Db* classes form the persistence boundary. They appear to be row-mapped representations of the domain objects used by the services, separating UI/business models from database-facing structures. The actual schema is defined in src/main/resources/sql file/database.sql.

11. Interfaces such as IMenuItem, IOrder, IPayment, IInventoryItem, IFoodWaste, and IMenuItemIngredient indicate the code uses explicit contracts for core entities. This suggests the system is organized around service-driven business logic with domain abstractions, rather than direct UI-to-database access.

12. Cross-cutting validation and error handling are first-class parts of the design. ValidationException, BusinessException, PaymentFailedException, and InsufficientInventoryException indicate that domain rules are enforced in the service layer and propagated back to the Swing UI for user feedback.

13. Resource folders for icons and images show the UI is polished and likely heavily desktop-oriented. The architecture is therefore best drawn as a client-side desktop application with local UI, service, and persistence layers, rather than a distributed microservice system.

14. For an architecture diagram, the clearest boundaries are:

- Presentation: Swing frames, panels, dialogs

- Application/domain services: auth, cashier, manager services

- Persistence: DB-mapped entities and database connection

- Shared infrastructure: user/auth/permission, exceptions, and role model

- External dependency: relational database defined by the bundled SQL schema