.大学生班级事务管理系统 主要功能模块： （1）班级人员管理模块 （2）不同级别登录人员对班级事务的增删查改等操作模块 （3）班级留言板功能模板 用java代码实现

下面是一个简单的Java代码实现，实现了班级人员管理、登录权限控制和班级留言板功能模块。具体的实现细节，可以根据具体需求进行修改和完善。

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

// 定义一个班级人员类
class Student {
    private String name;
    private String id;
    private String major;
    private String phone;

    public Student(String name, String id, String major, String phone) {
        this.name = name;
        this.id = id;
        this.major = major;
        this.phone = phone;
    }

    public String getName() {
        return name;
    }

    public String getId() {
        return id;
    }

    public String getMajor() {
        return major;
    }

    public String getPhone() {
        return phone;
    }

    @Override
    public String toString() {
        return "姓名：" + name + "，学号：" + id + "，专业：" + major + "，电话：" + phone;
    }
}

// 定义一个班级留言板类
class MessageBoard {
    private ArrayList<String> messages;

    public MessageBoard() {
        messages = new ArrayList<>();
    }

    public void addMessage(String message) {
        messages.add(message);
    }

    public void printMessages() {
        System.out.println("留言板：");
        for (String message : messages) {
            System.out.println(message);
        }
    }
}

// 定义一个班级管理系统类
public class ClassManagementSystem {
    private ArrayList<Student> students;
    private MessageBoard messageBoard;

    public ClassManagementSystem() {
        students = new ArrayList<>();
        messageBoard = new MessageBoard();
    }

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

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

    public void printStudents() {
        System.out.println("班级人员：");
        for (Student student : students) {
            System.out.println(student);
        }
    }

    public void login(int level) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入用户名：");
        String username = scanner.nextLine();
        System.out.println("请输入密码：");
        String password = scanner.nextLine();
        if (level == 1 && username.equals("admin") && password.equals("123456")) {
            System.out.println("管理员登录成功！");
            // 管理员可以进行增删改操作
            System.out.println("请选择操作：");
            System.out.println("1. 增加人员");
            System.out.println("2. 删除人员");
            System.out.println("3. 修改人员信息");
            int choice = scanner.nextInt();
            scanner.nextLine();
            if (choice == 1) {
                System.out.println("请输入姓名：");
                String name = scanner.nextLine();
                System.out.println("请输入学号：");
                String id = scanner.nextLine();
                System.out.println("请输入专业：");
                String major = scanner.nextLine();
                System.out.println("请输入电话：");
                String phone = scanner.nextLine();
                Student student = new Student(name, id, major, phone);
                addStudent(student);
                System.out.println("人员添加成功！");
            } else if (choice == 2) {
                System.out.println("请输入要删除的学号：");
                String id = scanner.nextLine();
                for (Student student : students) {
                    if (student.getId().equals(id)) {
                        removeStudent(student);
                        System.out.println("人员删除成功！");
                        break;
                    }
                }
            } else if (choice == 3) {
                System.out.println("请输入要修改的学号：");
                String id = scanner.nextLine();
                for (Student student : students) {
                    if (student.getId().equals(id)) {
                        System.out.println("请输入新的姓名（留空表示不修改）：");
                        String name = scanner.nextLine();
                        System.out.println("请输入新的专业（留空表示不修改）：");
                        String major = scanner.nextLine();
                        System.out.println("请输入新的电话（留空表示不修改）：");
                        String phone = scanner.nextLine();
                        if (!name.isEmpty()) {
                            student = new Student(name, student.getId(), student.getMajor(), student.getPhone());
                        }
                        if (!major.isEmpty()) {
                            student = new Student(student.getName(), student.getId(), major, student.getPhone());
                        }
                        if (!phone.isEmpty()) {
                            student = new Student(student.getName(), student.getId(), student.getMajor(), phone);
                        }
                        System.out.println("人员修改成功！");
                        break;
                    }
                }
            } else {
                System.out.println("无效操作！");
            }
        } else if (level == 2 && username.equals("user") && password.equals("123456")) {
            System.out.println("普通用户登录成功！");
            // 普通用户可以查看班级人员和留言板
            System.out.println("请选择操作：");
            System.out.println("1. 查看班级人员");
            System.out.println("2. 查看留言板");
            int choice = scanner.nextInt();
            scanner.nextLine();
            if (choice == 1) {
                printStudents();
            } else if (choice == 2) {
                messageBoard.printMessages();
            } else {
                System.out.println("无效操作！");
            }
        } else {
            System.out.println("用户名或密码错误！");
        }
    }

    public void addMessage(String message) {
        messageBoard.addMessage(message);
    }

    public static void main(String[] args) {
        ClassManagementSystem system = new ClassManagementSystem();
        system.addStudent(new Student("张三", "1001", "计算机科学与技术", "12345678901"));
        system.addStudent(new Student("李四", "1002", "软件工程", "12345678902"));
        system.addStudent(new Student("王五", "1003", "信息管理", "12345678903"));
        Scanner scanner = new Scanner(System.in);
        while (true) {
            System.out.println("请选择登录级别：");
            System.out.println("1. 管理员");
            System.out.println("2. 普通用户");
            int level = scanner.nextInt();
            scanner.nextLine();
            system.login(level);
        }
    }
}