Case Study: Employee Management System in Java
1. Introduction
In modern organizations, managing employees and departments efficiently is vital for
smooth operations. This case study outlines the creation of an Employee Management
System (EMS) in Java using object-oriented programming (OOP) principles like inheritance,
encapsulation, and polymorphism.
2. Objective
To develop a Java-based system that:
Manages employee data (name, ID, position)
Organizes employees into departments
Supports different employee types like Manager and Developer
Displays employee hierarchy
3. Key Features
Add and assign employees to departments
Inherit employee types (Manager, Developer) from base Employee
Display structured department-wise employee listings
Hierarchical view (Manager > Developers)
4. Class Structure
Employee (Base Class)
├── Manager (Subclass)
└── Developer (Subclass)
Department
└── List of Employees
5. Java Programs
a) Employee.java
Public class Employee {
Protected int id;
Protected String name;
Protected String position;
Public Employee(int id, String name, String position) {
This.id = id;
This.name = name;
This.position = position;
Public void displayInfo() {
System.out.println(“ID: “ + id + “, Name: “ + name + “, Position: “ + position);
}
b) Manager.java
Public class Manager extends Employee {
Public Manager(int id, String name) {
Super(id, name, “Manager”);
Public void manageTeam() {
System.out.println(name + “ is managing the team.”);
c) Developer.java
Public class Developer extends Employee {
Public Developer(int id, String name) {
Super(id, name, “Developer”);
Public void writeCode() {
System.out.println(name + “ is writing code.”);
}
d) Department.java
Import java.util.*;
Public class Department {
Private String deptName;
Private List<Employee> employees;
Public Department(String deptName) {
This.deptName = deptName;
Employees = new ArrayList<>();
Public void addEmployee(Employee emp) {
Employees.add(emp);
Public void showDepartmentStructure() {
System.out.println(“\nDepartment: “ + deptName);
For (Employee emp : employees) {
Emp.displayInfo();
}
e) Main.java
Public class Main {
Public static void main(String[] args) {
// Create Employees
Manager m1 = new Manager(1, “Suvithra”);
Developer d1 = new Developer(2, “Rahul”);
Developer d2 = new Developer(3, “Karthik”);
// Create Departments
Department devDept = new Department(“Development”);
Department hrDept = new Department(“Human Resources”);
// Add Employees to Departments
devDept.addEmployee(m1);
devDept.addEmployee(d1);
devDept.addEmployee(d2);
// Display Structure
devDept.showDepartmentStructure();
// Demonstrate behavior
M1.manageTeam();
D1.writeCode();
D2.writeCode();
}
6. Output Example
Department: Development
ID: 1, Name: Suvithra, Position: Manager
ID: 2, Name: Rahul, Position: Developer
ID: 3, Name: Karthik, Position: Developer
Suvithra is managing the team.
Rahul is writing code.
Karthik is writing code.
7. Conclusion
This case study demonstrates how inheritance and class hierarchy in Java can be used to
build a modular and maintainable Employee Management System. It showcases OOP
principles and how to logically organize data and behavior for real-world scenarios like
employee-department management.
