Object Oriented Concepts

Daffodil International University Faculty of Science & Information Technology Department of Information Technology & Management Final Examination, Summer 2025 Course Code: ITM213; Course Title: Object Oriented Concepts Sections & Teachers: MA Time: 2:00 Hrs Marks: 40 Answer ALL Questions In a Supershop Management System, the base class Person is introduced to represent individuals interacting with the system. It contains two attributes (name, contact) and two methods (displayInfo(), updateInfo()), and serves as a parent class for Customer and Employee. Through inheritance, both Customer and Employee override the displayInfo() method to present information specific to their roles. The Customer class adds attributes like customerId and loyaltyPoints, with methods addPoints() and redeemPoints(). The Employee class, through constructor chaining, introduces attributes like employeeId and role, along with methods assignTask() and calculateSalary(). Employees are further specialized into Cashier and Manager, illustrating deeper inheritance. The Product class represents items in the store, with attributes (productCode, price) and methods (getDetails(), applyDiscount()). It is linked to the Category class, where each product must belong to exactly one category (e.g., Grocery, Electronics), and a category cannot exist independently of its products. On the other hand, a ShoppingCart class demonstrates holding multiple Product objects temporarily, while still allowing those products to exist independently of the cart. The Bill class shows association with both Customer and cashier — a bill is generated by a cashier for a particular customer. It contains attributes (billId, totalAmount) and methods (generateBill(), printBill()). To handle flexible billing operations, the Bill class includes an overloaded method addItem(), which has three different implementations: one version accepts only a Product, another accepts a Product with a quantity, and a third accepts a Product, quantity, and a discount percentage and prints the details. Every class provides getter and setter methods for controlled access to attributes, applying appropriate access modifiers. 1. a) Design an UML class diagram for the above scenario. Design the classes and relationship among the classes properly and justify your choice. [Marks-10] 2. a) Implement the Person, customer and Employee classes in python. Implement constructor chaining, method overriding properly. Create objects of each class, call the methods and show the output [Marks-5] b) Consider the Bill class. Implement method overloading using dispatcher module. [Marks-5] c) Consider the Product class, implement it as an abstract class. Derive a class "S_product" from the abstract class with specific method implementation. [Marks-5] 3. a) Differentiate between method overloading and method overriding in your own words. Explain the role of method resolution order (MRO) in method overriding concept. [Marks-5] b) Define polymorphism and encapsulation in your own words. Explain different types of access modifiers with scope of each access modifiers [Marks-5] 4. a) In a Student Result Management System, the program stores student marks in a list. When a user tries to access the marks of a student by providing an index, there is a possibility that the entered index is outside the valid range of the list. To handle this situation, the system applies a try block for accessing the mark, an except block to catch invalid index access, an else block to display the mark when the index is valid, and a finally block to show a closing message like "Operation Completed. Closing Result System. Now implement the above scenario in python. [Marks-5]