StudentManagementSystem.java

import java.io.*;
import java.util.*;

public class StudentManagementSystem {
    private List<Student> students = new ArrayList<>();
    private final String filePath = "students.dat"; // File for saving data

    // Constructor: Load students from file
    public StudentManagementSystem() {
        loadFromFile();
    }

    // Add a new student
    public void addStudent(Student student) {
        students.add(student);
        System.out.println("Student added successfully!");
        saveToFile();
    }

    // Remove a student by roll number
    public boolean removeStudent(int rollNumber) {
        Iterator<Student> iterator = students.iterator();
        while (iterator.hasNext()) {
            Student student = iterator.next();
            if (student.getRollNumber() == rollNumber) {
                iterator.remove();
                System.out.println("Student removed successfully!");
                saveToFile();
                return true;
            }
        }
        System.out.println("Student with roll number " + rollNumber + " not found.");
        return false;
    }

    // Search for a student by roll number
    public Student searchStudent(int rollNumber) {
        for (Student student : students) {
            if (student.getRollNumber() == rollNumber) {
                return student;
            }
        }
        System.out.println("Student with roll number " + rollNumber + " not found.");
        return null;
    }

    // Display all students
    public void displayAllStudents() {
        if (students.isEmpty()) {
            System.out.println("No students found.");
        } else {
            System.out.println("=== Student List ===");
            for (Student student : students) {
                System.out.println(student);
            }
        }
    }

    // Save student list to a file
    private void saveToFile() {
        try (ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream(filePath))) {
            oos.writeObject(students);
        } catch (IOException e) {
            System.out.println("Error saving student data: " + e.getMessage());
        }
    }

    // Load student list from a file
    @SuppressWarnings("unchecked")
    private void loadFromFile() {
        File file = new File(filePath);
        if (file.exists()) {
            try (ObjectInputStream ois = new ObjectInputStream(new FileInputStream(file))) {
                students = (List<Student>) ois.readObject();
            } catch (IOException | ClassNotFoundException e) {
                System.out.println("Error loading student data: " + e.getMessage());
            }
        }
    }
}