StudentManager.java

// StudentManager.java
import java.io.*;
import java.util.*;

public class StudentManager {
    Scanner scanner = new Scanner(System.in);
    String fileName = "students.txt";

    public void addStudent() {
        System.out.print("Enter Name: ");
        String name = scanner.nextLine();
        System.out.print("Enter Roll Number: ");
        String roll = scanner.nextLine();
        System.out.print("Enter Department: ");
        String dept = scanner.nextLine();
        System.out.print("Enter Email: ");
        String email = scanner.nextLine();

        try (BufferedWriter writer = new BufferedWriter(new FileWriter(fileName, true))) {
            writer.write(name + "," + roll + "," + dept + "," + email);
            writer.newLine();
            System.out.println("✅ Student added and saved to file!");
        } catch (IOException e) {
            System.out.println("❌ Error saving student: " + e.getMessage());
        }
    }

    public void viewAll() {
        File file = new File(fileName);
        if (!file.exists() || file.length() == 0) {
            System.out.println("❗ No student records found.");
            return;
        }

        System.out.println("\n🎓 All Student Records:");
        try (BufferedReader reader = new BufferedReader(new FileReader(file))) {
            String line;
            while ((line = reader.readLine()) != null) {
                String[] data = line.split(",");
                System.out.println("Name: " + data[0]);
                System.out.println("Roll No: " + data[1]);
                System.out.println("Department: " + data[2]);
                System.out.println("Email: " + data[3]);
                System.out.println("-----------------------------");
            }
        } catch (IOException e) {
            System.out.println("❌ Error reading file: " + e.getMessage());
        }
    }

    public void searchStudent() {
        System.out.print("Enter Roll Number to search: ");
        String roll = scanner.nextLine();
        boolean found = false;

        try (BufferedReader reader = new BufferedReader(new FileReader(fileName))) {
            String line;
            while ((line = reader.readLine()) != null) {
                String[] data = line.split(",");
                if (data[1].equalsIgnoreCase(roll)) {
                    System.out.println("\n🎯 Student Found:");
                    System.out.println("Name: " + data[0]);
                    System.out.println("Roll No: " + data[1]);
                    System.out.println("Department: " + data[2]);
                    System.out.println("Email: " + data[3]);
                    found = true;
                    break;
                }
            }
        } catch (IOException e) {
            System.out.println("❌ Error reading file: " + e.getMessage());
        }

        if (!found) {
            System.out.println("❌ Student not found.");
        }
    }
}