In this tutorial, we’ll build a simple Java application for managing employment details. We’ll create classes for employees, managers, and departments, and explain each step with comments for beginners to understand.
1. Employee Class
/**
* The Employee class represents individual employees in the organization.
*/
public class Employee {
// Attributes
private int id; // Unique identifier for each employee
private String name; // Name of the employee
private double salary; // Salary of the employee
// Constructor
public Employee(int id, String name, double salary) {
// Initialize attributes with provided values
this.id = id;
this.name = name;
this.salary = salary;
}
// Getters and Setters
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getSalary() {
return salary;
}
public void setSalary(double salary) {
this.salary = salary;
}
// Method to display employee details
public void displayDetails() {
System.out.println("Employee ID: " + id);
System.out.println("Name: " + name);
System.out.println("Salary: " + salary);
}
}
Explanation:
- The
Employeeclass represents individual employees in the organization. - It has three attributes:
id,name, andsalaryto store employee information. - The constructor method
Employeeinitializes these attributes when a new employee object is created. - Getters (
getId,getName,getSalary) and setters (setId,setName,setSalary) are provided to access and modify the attributes. - The
displayDetailsmethod prints the employee’s ID, name, and salary to the console.
2. Manager Class
/**
* The Manager class represents managers in the organization.
* It extends the Employee class.
*/
public class Manager extends Employee {
// Additional attribute
private String department; // Department managed by the manager
// Constructor
public Manager(int id, String name, double salary, String department) {
// Call the constructor of the superclass (Employee) to initialize inherited attributes
super(id, name, salary);
// Initialize additional attribute specific to managers
this.department = department;
}
// Getter and Setter for department
public String getDepartment() {
return department;
}
public void setDepartment(String department) {
this.department = department;
}
// Overriding displayDetails method to include department
@Override
public void displayDetails() {
// Call the displayDetails method of the superclass (Employee) to print employee details
super.displayDetails();
// Print additional details specific to managers
System.out.println("Department: " + department);
}
}
Explanation:
- The
Managerclass represents managers in the organization and extends theEmployeeclass. - It adds an extra attribute
departmentto store the department managed by the manager. - The constructor method
Managerinitializes all attributes, including those inherited from theEmployeeclass. - Getter and setter methods are provided for the
departmentattribute. - The
displayDetailsmethod overrides the method in the superclass to include the department information when displaying manager details.
3. Department Class
import java.util.ArrayList;
import java.util.List;
/**
* The Department class represents departments in the organization.
*/
public class Department {
// Attributes
private String name; // Name of the department
private List<Employee> employees; // List of employees in the department
// Constructor
public Department(String name) {
// Initialize department name
this.name = name;
// Initialize list to store employees
employees = new ArrayList<>();
}
// Getter and Setter for name
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
// Method to add an employee to the department
public void addEmployee(Employee employee) {
// Add employee to the list
employees.add(employee);
}
// Method to display department details
public void displayDetails() {
// Print department name
System.out.println("Department Name: " + name);
// Iterate through the list of employees and print their details
System.out.println("Employees:");
for (Employee emp : employees) {
emp.displayDetails();
}
}
}
Explanation:
- The
Departmentclass represents departments in the organization. - It has two attributes:
nameto store the department name andemployeesto store a list of employees in the department. - The constructor method
Departmentinitializes the department name and creates an empty list of employees. - Getter and setter methods are provided for the
nameattribute. - The
addEmployeemethod adds an employee to the department’s list of employees. - The
displayDetailsmethod prints the department name and the details of all employees in the department.
