Assignment Introduction

This practice assignment is designed to help you apply the Object-Oriented Programming concepts learned in this chapter. Until now, you have studied important OOP topics such as class, object, properties, methods, constructor, encapsulation, inheritance, polymorphism, abstraction, interface, and composition.

Now it is time to use these concepts in a practical project-based assignment. In this assignment, you will design a Student Management System. This system will manage student details, course information, address details, marks, grades, reports, and notifications.

The goal of this assignment is not only to write code, but also to learn how to think like a software designer. You should first identify the classes, their properties, their methods, and the relationships between them. After that, you can create a simple implementation using any object-oriented programming language such as Java, C#, Python, JavaScript, PHP, or C++.

Assignment Objective

The main objective of this assignment is to design a basic Student Management System using Object-Oriented Programming principles. Students should be able to understand how real-world entities can be converted into classes and objects.

Prerequisites

Before attempting this assignment, students should have a basic understanding of the following concepts. These prerequisites will help students complete the assignment smoothly.

Problem Statement

Design a simple Student Management System using Object-Oriented Programming. The system should store and manage student details, course details, address information, marks, grade calculation, and report generation.

Your task is to identify the required classes, define their properties and methods, apply OOP principles, and create a simple working model of the system.

Functional Requirements

Functional requirements describe what the system should do. Your Student Management System should support the following features:

Non-Functional Requirements

Non-functional requirements describe how the system should be designed. Your solution should follow clean OOP design principles.

Step 1: Identify Classes

The first step in designing this project is identifying the possible classes. In OOP, classes usually come from important nouns in the problem statement.

From the problem statement, we can identify the following possible classes:

Step 2: Identify Properties / Attributes

After identifying classes, we should define what data each class will store. These data items become properties or attributes.

Step 3: Identify Methods

Methods represent the actions or behavior of an object. Look for verbs in the requirement to identify possible methods.

Step 4: Identify OOP Relationships

A good OOP design requires identifying relationships between classes. This helps us decide where to use inheritance, composition, interface, and polymorphism.

Suggested Class Design

The following design shows how classes can be connected in this assignment.

// Suggested class relationship overview

Person
  |
  |-- Student

Student has Address
Student has Course
Student has Result

ReportGenerator interface
  |
  |-- MarksReport

NotificationService sends notification

Assignment Task 1: Create the Person Class

Create a Person class to store common personal details. This class will act as a parent class for Student.

class Person {

    protected String name;
    protected int age;
    protected String contactNumber;

    Person(String personName, int personAge, String contact) {
        name = personName;
        age = personAge;
        contactNumber = contact;
    }

    void displayBasicDetails() {
        System.out.println("Name: " + name);
        System.out.println("Age: " + age);
        System.out.println("Contact Number: " + contactNumber);
    }
}

Assignment Task 2: Create the Address Class

Create an Address class to store address details. This class will be used inside the Student class through composition.

class Address {

    private String city;
    private String state;
    private String country;
    private String postalCode;

    Address(String studentCity, String studentState, String studentCountry, String studentPostalCode) {
        city = studentCity;
        state = studentState;
        country = studentCountry;
        postalCode = studentPostalCode;
    }

    void displayAddress() {
        System.out.println("City: " + city);
        System.out.println("State: " + state);
        System.out.println("Country: " + country);
        System.out.println("Postal Code: " + postalCode);
    }
}

Assignment Task 3: Create the Course Class

Create a Course class to store course information. A student should have one course object.

class Course {

    private String courseCode;
    private String courseName;
    private int durationInMonths;

    Course(String code, String name, int duration) {
        courseCode = code;
        courseName = name;
        durationInMonths = duration;
    }

    void displayCourseDetails() {
        System.out.println("Course Code: " + courseCode);
        System.out.println("Course Name: " + courseName);
        System.out.println("Duration: " + durationInMonths + " months");
    }
}

Assignment Task 4: Create the Result Class

Create a Result class to store marks and calculate grade. This class should properly apply encapsulation because marks should not be stored with invalid values.

class Result {

    private int marks;

    Result(int studentMarks) {
        setMarks(studentMarks);
    }

    void setMarks(int studentMarks) {
        if (studentMarks >= 0 && studentMarks <= 100) {
            marks = studentMarks;
        } else {
            marks = 0;
            System.out.println("Invalid marks. Marks must be between 0 and 100.");
        }
    }

    int getMarks() {
        return marks;
    }

    String calculateGrade() {
        if (marks >= 90) {
            return "A";
        } else if (marks >= 75) {
            return "B";
        } else if (marks >= 60) {
            return "C";
        } else if (marks >= 40) {
            return "D";
        } else {
            return "Fail";
        }
    }

    boolean isPassed() {
        return marks >= 40;
    }

    void displayResult() {
        System.out.println("Marks: " + marks);
        System.out.println("Grade: " + calculateGrade());
        System.out.println("Status: " + (isPassed() ? "Passed" : "Failed"));
    }
}

Assignment Task 5: Create the Student Class

Create a Student class that inherits from Person and uses Address, Course, and Result objects through composition.

class Student extends Person {

    private String studentId;
    private int rollNumber;
    private Address address;
    private Course course;
    private Result result;

    Student(String id, String studentName, int studentAge, String contact, int roll, Address studentAddress, Course studentCourse, Result studentResult) {
        super(studentName, studentAge, contact);
        studentId = id;
        rollNumber = roll;
        address = studentAddress;
        course = studentCourse;
        result = studentResult;
    }

    void displayStudentProfile() {
        System.out.println("Student ID: " + studentId);
        displayBasicDetails();
        System.out.println("Roll Number: " + rollNumber);

        System.out.println("--- Address Details ---");
        address.displayAddress();

        System.out.println("--- Course Details ---");
        course.displayCourseDetails();

        System.out.println("--- Result Details ---");
        result.displayResult();
    }

    Result getResult() {
        return result;
    }

    String getStudentName() {
        return name;
    }
}

Assignment Task 6: Create a ReportGenerator Interface

Create an interface called ReportGenerator. This interface should define a common method named generateReport().

interface ReportGenerator {

    void generateReport();
}

class MarksReport implements ReportGenerator {

    private Student student;

    MarksReport(Student reportStudent) {
        student = reportStudent;
    }

    public void generateReport() {
        System.out.println("===== Student Marks Report =====");
        System.out.println("Student Name: " + student.getStudentName());
        System.out.println("Marks: " + student.getResult().getMarks());
        System.out.println("Grade: " + student.getResult().calculateGrade());
        System.out.println("Status: " + (student.getResult().isPassed() ? "Passed" : "Failed"));
    }
}

Assignment Task 7: Create NotificationService Class

Create a NotificationService class to send simple notification messages. This class demonstrates separation of responsibility.

class NotificationService {

    void sendNotification(String message) {
        System.out.println("Notification: " + message);
    }
}

Complete Assignment Sample Solution in Java

The following sample solution combines all classes and demonstrates a basic working Student Management System. Students can use this as a reference after trying the assignment themselves.

class Person {

    protected String name;
    protected int age;
    protected String contactNumber;

    Person(String personName, int personAge, String contact) {
        name = personName;
        age = personAge;
        contactNumber = contact;
    }

    void displayBasicDetails() {
        System.out.println("Name: " + name);
        System.out.println("Age: " + age);
        System.out.println("Contact Number: " + contactNumber);
    }
}

class Address {

    private String city;
    private String state;
    private String country;
    private String postalCode;

    Address(String studentCity, String studentState, String studentCountry, String studentPostalCode) {
        city = studentCity;
        state = studentState;
        country = studentCountry;
        postalCode = studentPostalCode;
    }

    void displayAddress() {
        System.out.println("City: " + city);
        System.out.println("State: " + state);
        System.out.println("Country: " + country);
        System.out.println("Postal Code: " + postalCode);
    }
}

class Course {

    private String courseCode;
    private String courseName;
    private int durationInMonths;

    Course(String code, String name, int duration) {
        courseCode = code;
        courseName = name;
        durationInMonths = duration;
    }

    void displayCourseDetails() {
        System.out.println("Course Code: " + courseCode);
        System.out.println("Course Name: " + courseName);
        System.out.println("Duration: " + durationInMonths + " months");
    }
}

class Result {

    private int marks;

    Result(int studentMarks) {
        setMarks(studentMarks);
    }

    void setMarks(int studentMarks) {
        if (studentMarks >= 0 && studentMarks <= 100) {
            marks = studentMarks;
        } else {
            marks = 0;
            System.out.println("Invalid marks. Marks must be between 0 and 100.");
        }
    }

    int getMarks() {
        return marks;
    }

    String calculateGrade() {
        if (marks >= 90) {
            return "A";
        } else if (marks >= 75) {
            return "B";
        } else if (marks >= 60) {
            return "C";
        } else if (marks >= 40) {
            return "D";
        } else {
            return "Fail";
        }
    }

    boolean isPassed() {
        return marks >= 40;
    }

    void displayResult() {
        System.out.println("Marks: " + marks);
        System.out.println("Grade: " + calculateGrade());
        System.out.println("Status: " + (isPassed() ? "Passed" : "Failed"));
    }
}

class Student extends Person {

    private String studentId;
    private int rollNumber;
    private Address address;
    private Course course;
    private Result result;

    Student(String id, String studentName, int studentAge, String contact, int roll, Address studentAddress, Course studentCourse, Result studentResult) {
        super(studentName, studentAge, contact);
        studentId = id;
        rollNumber = roll;
        address = studentAddress;
        course = studentCourse;
        result = studentResult;
    }

    void displayStudentProfile() {
        System.out.println("===== Student Profile =====");
        System.out.println("Student ID: " + studentId);
        displayBasicDetails();
        System.out.println("Roll Number: " + rollNumber);

        System.out.println("--- Address Details ---");
        address.displayAddress();

        System.out.println("--- Course Details ---");
        course.displayCourseDetails();

        System.out.println("--- Result Details ---");
        result.displayResult();
    }

    Result getResult() {
        return result;
    }

    String getStudentName() {
        return name;
    }
}

interface ReportGenerator {

    void generateReport();
}

class MarksReport implements ReportGenerator {

    private Student student;

    MarksReport(Student reportStudent) {
        student = reportStudent;
    }

    public void generateReport() {
        System.out.println("===== Student Marks Report =====");
        System.out.println("Student Name: " + student.getStudentName());
        System.out.println("Marks: " + student.getResult().getMarks());
        System.out.println("Grade: " + student.getResult().calculateGrade());
        System.out.println("Status: " + (student.getResult().isPassed() ? "Passed" : "Failed"));
    }
}

class NotificationService {

    void sendNotification(String message) {
        System.out.println("Notification: " + message);
    }
}

public class Main {
    public static void main(String[] args) {

        Address address1 = new Address("Kolkata", "West Bengal", "India", "700001");
        Course course1 = new Course("PL101", "Programming Fundamentals", 6);
        Result result1 = new Result(85);

        Student student1 = new Student("S101", "Rahul", 20, "9876543210", 101, address1, course1, result1);

        student1.displayStudentProfile();

        ReportGenerator report = new MarksReport(student1);
        report.generateReport();

        NotificationService notificationService = new NotificationService();
        notificationService.sendNotification("Marks report generated successfully for " + student1.getStudentName());
    }
}

Expected Output

The exact output may vary depending on formatting, but the output should look similar to this:

===== Student Profile =====
Student ID: S101
Name: Rahul
Age: 20
Contact Number: 9876543210
Roll Number: 101
--- Address Details ---
City: Kolkata
State: West Bengal
Country: India
Postal Code: 700001
--- Course Details ---
Course Code: PL101
Course Name: Programming Fundamentals
Duration: 6 months
--- Result Details ---
Marks: 85
Grade: B
Status: Passed
===== Student Marks Report =====
Student Name: Rahul
Marks: 85
Grade: B
Status: Passed
Notification: Marks report generated successfully for Rahul

OOP Concepts Applied in This Assignment

The following table explains how different OOP concepts are used in this assignment.

Assignment Questions for Students

Students should answer the following questions after completing the assignment. These questions help test conceptual understanding.

Extension Tasks

After completing the basic assignment, students can improve the project by adding more features. These extension tasks are optional but highly recommended.

Evaluation Criteria

The assignment can be evaluated using the following criteria.

Common Mistakes to Avoid

Students should avoid the following mistakes while completing this assignment.

Best Practices for This Assignment

Follow these best practices to write a clean and professional solution.

Frequently Asked Questions

1. What is the main goal of this assignment?

The main goal is to apply Object-Oriented Programming concepts by designing a Student Management System using classes, objects, properties, methods, constructors, encapsulation, inheritance, composition, interface, abstraction, and polymorphism.

2. Which class should be the parent class?

The Person class can be used as the parent class because common personal details such as name, age, and contact number can be reused by Student and other future classes such as Teacher.

3. Why should Student have Address instead of inheriting Address?

Because Student is not an Address. A Student has an Address. Therefore, composition is the correct relationship.

4. Where is encapsulation used?

Encapsulation is used in the Result class by keeping marks private and updating marks through setMarks() with validation.

5. Where is inheritance used?

Inheritance is used when Student extends Person. This represents an is-a relationship because a student is a person.

6. Where is composition used?

Composition is used when Student contains Address, Course, and Result objects. This represents has-a relationships.

7. Why is ReportGenerator an interface?

ReportGenerator defines a common contract for generating reports. Different report classes can implement this interface and generate different types of reports.

8. How is polymorphism used?

Polymorphism is used when a ReportGenerator reference points to a MarksReport object and calls generateReport(). In the future, the same interface can be used for AttendanceReport or FeeReport.

9. Can this assignment be done in languages other than Java?

Yes. The same design can be implemented in any object-oriented programming language such as C#, Python, JavaScript, PHP, C++, Kotlin, or Swift. The syntax will change, but the OOP design remains the same.

10. What should students submit?

Students should submit class design, source code, sample output, and a short explanation of where each OOP concept is used.

Assignment Summary

This assignment helps students practice Object-Oriented Programming using a practical Student Management System. Students must identify classes, define properties and methods, use constructors, and apply important OOP concepts in a meaningful way.

The assignment demonstrates inheritance through Student and Person, composition through Student with Address, Course, and Result, encapsulation through private marks, abstraction through report generation, interface through ReportGenerator, and polymorphism through report implementation.

By completing this assignment, students will understand how OOP concepts work together in real-world application design. This assignment also prepares students for larger projects such as Library Management System, Banking System, E-Commerce System, and Hospital Management System.