仅用Java实现学生信息管理系统

以下是一个仅使用Java实现学生信息管理系统的例子：

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

public class StudentManagementSystem {
    private ArrayList<Student> students;

    public StudentManagementSystem() {
        students = new ArrayList<>();
    }

    public void addStudent(Student student) {
        students.add(student);
    }

    public void removeStudent(Student student) {
        students.remove(student);
    }

    public void displayAllStudents() {
        for (Student student : students) {
            System.out.println(student);
        }
    }

    public void displayStudentById(int id) {
        for (Student student : students) {
            if (student.getId() == id) {
                System.out.println(student);
                return;
            }
        }
        System.out.println("No student found with id " + id);
    }

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

        while (true) {
            System.out.println("1. Add student");
            System.out.println("2. Remove student");
            System.out.println("3. Display all students");
            System.out.println("4. Display student by id");
            System.out.println("5. Exit");
            System.out.print("Enter your choice: ");
            int choice = scanner.nextInt();

            switch (choice) {
                case 1:
                    System.out.print("Enter student id: ");
                    int id = scanner.nextInt();
                    System.out.print("Enter student name: ");
                    String name = scanner.next();
                    System.out.print("Enter student age: ");
                    int age = scanner.nextInt();
                    Student student = new Student(id, name, age);
                    system.addStudent(student);
                    System.out.println("Student added successfully");
                    break;
                case 2:
                    System.out.print("Enter student id: ");
                    id = scanner.nextInt();
                    student = new Student(id, "", 0);
                    system.removeStudent(student);
                    System.out.println("Student removed successfully");
                    break;
                case 3:
                    system.displayAllStudents();
                    break;
                case 4:
                    System.out.print("Enter student id: ");
                    id = scanner.nextInt();
                    system.displayStudentById(id);
                    break;
                case 5:
                    System.exit(0);
                    break;
                default:
                    System.out.println("Invalid choice");
            }
        }
    }
}

class Student {
    private int id;
    private String name;
    private int age;

    public Student(int id, String name, int age) {
        this.id = id;
        this.name = name;
        this.age = age;
    }

    public int getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }

    @Override
    public String toString() {
        return "Student{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}