Student_management_system.java

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

class Student{
  private String name;
  private int rollNumber;
  private String grade;

public Student(String name, int rollNumber, String grade){
 this.name=name;
 this.rollNumber=rollNumber;
 this.grade=grade;
}

public int getRollNumber(){
  return rollNumber;
}
@Override
public String toString(){
 return "Name: "+ name+ ",Roll Number: " + rollNumber+ ",Grade: "+grade;

}
}
class StudentManagementSystem{
 private List<Student> students;

public StudentManagementSystem(){
  students = new ArrayList<>();
}
public void addStudent(Student student){
  students.add(student);
}
public boolean removeStudent(int rollNumber){
 for(Student student : students){
   if(student.getRollNumber() == rollNumber){
      students.remove(student);
      return true;
}
}
return false;
}

public Student searchStudent(int rollNumber){
 for(Student student : students){
   if(student.getRollNumber() == rollNumber){
      
      return student;

}
}
 return null;
}
 public List<Student> getAllStudents(){
  return students;
}
}

public class Student_management_system{
public static void main(String[] args){
 Scanner scanner= new Scanner(System.in);
 StudentManagementSystem sms= new StudentManagementSystem();

while(true){
 System.out.println("1. Add Student");
System.out.println("2. Remove Student");
System.out.println("3. Search Student");
System.out.println("4. Display All Student");
System.out.println("5. Exit");
System.out.println("Enter your choice:");
int choice = scanner.nextInt();

switch(choice){
 case 1:
  scanner.nextLine();
  System.out.print("Enter student name: ");
  String name = scanner.nextLine();
  System.out.println("Enter roll number: ");
  int rollNumber = scanner.nextInt();
  scanner.nextLine();
  System.out.println("Enter grade: ");
  String grade = scanner.nextLine();

  Student newStudent = new Student(name, rollNumber, grade);
  sms.addStudent(newStudent);
  System.out.println("Student added.");
  break;

case 2:
  System.out.println("Enter roll number of student to remove: ");
  int rollToRemove = scanner.nextInt();
  boolean removed = sms.removeStudent(rollToRemove);
  if(removed){
     System.out.println("Student removed.");
  }
  else{
  System.out.println("Student not found.");
}
  break;

case 3:
  System.out.println("Enter roll number of student to search: ");
  int rollToSearch = scanner.nextInt();
  Student searchedStudent = sms.searchStudent(rollToSearch);
  if(searchedStudent != null){
    System.out.println("Student found:");
    System.out.println(searchedStudent);
}
  else{
    System.out.println("Student not found.");
}
  break;

case 4:
  List<Student> allStudents = sms.getAllStudents();
  if (allStudents.isEmpty()){
    System.out.println("No students to display.");
}else{
 System.out.println("All Students.");
 for(Student student : allStudents){
   System.out.println(student);
}
}
break;

case 5:
  System.out.println("Exiting...");
  scanner.close();
  System.exit(0);
  break;
default:
  System.out.println("Invalid choice. Please choose again..");
break;

}
}



}
}