用java写一个管理系统

很抱歉，我是一个AI语言模型，无法实际编写程序。不过，以下是一个简单的Java管理系统的示例，希望能够帮助你了解如何开始编写一个管理系统：

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

public class ManagementSystem {
    private ArrayList<Employee> employees;
    private Scanner scanner;

    public ManagementSystem() {
        employees = new ArrayList<>();
        scanner = new Scanner(System.in);
    }

    public void run() {
        boolean exit = false;
        while (!exit) {
            System.out.println("请选择操作：");
            System.out.println("1. 添加员工");
            System.out.println("2. 删除员工");
            System.out.println("3. 查找员工");
            System.out.println("4. 修改员工信息");
            System.out.println("5. 显示所有员工");
            System.out.println("6. 退出系统");

            int choice = scanner.nextInt();

            switch (choice) {
                case 1:
                    addEmployee();
                    break;
                case 2:
                    deleteEmployee();
                    break;
                case 3:
                    searchEmployee();
                    break;
                case 4:
                    modifyEmployee();
                    break;
                case 5:
                    displayAllEmployees();
                    break;
                case 6:
                    exit = true;
                    break;
                default:
                    System.out.println("无效的选择，请重新输入！");
                    break;
            }
        }
    }

    private void addEmployee() {
        System.out.println("请输入员工姓名：");
        String name = scanner.next();

        System.out.println("请输入员工年龄：");
        int age = scanner.nextInt();

        System.out.println("请输入员工工资：");
        double salary = scanner.nextDouble();

        Employee employee = new Employee(name, age, salary);
        employees.add(employee);

        System.out.println("添加成功！");
    }

    private void deleteEmployee() {
        System.out.println("请输入要删除的员工的姓名：");
        String name = scanner.next();

        Employee employee = searchEmployeeByName(name);

        if (employee != null) {
            employees.remove(employee);
            System.out.println("删除成功！");
        } else {
            System.out.println("找不到该员工！");
        }
    }

    private void searchEmployee() {
        System.out.println("请输入要查找的员工的姓名：");
        String name = scanner.next();

        Employee employee = searchEmployeeByName(name);

        if (employee != null) {
            System.out.println("找到了该员工的信息：");
            System.out.println(employee.toString());
        } else {
            System.out.println("找不到该员工！");
        }
    }

    private void modifyEmployee() {
        System.out.println("请输入要修改的员工的姓名：");
        String name = scanner.next();

        Employee employee = searchEmployeeByName(name);

        if (employee != null) {
            System.out.println("请输入修改后的员工姓名：");
            String newName = scanner.next();
            employee.setName(newName);

            System.out.println("请输入修改后的员工年龄：");
            int newAge = scanner.nextInt();
            employee.setAge(newAge);

            System.out.println("请输入修改后的员工工资：");
            double newSalary = scanner.nextDouble();
            employee.setSalary(newSalary);

            System.out.println("修改成功！");
        } else {
            System.out.println("找不到该员工！");
        }
    }

    private void displayAllEmployees() {
        System.out.println("所有员工的信息如下：");
        for (Employee employee : employees) {
            System.out.println(employee.toString());
        }
    }

    private Employee searchEmployeeByName(String name) {
        for (Employee employee : employees) {
            if (employee.getName().equals(name)) {
                return employee;
            }
        }
        return null;
    }
}

这是一个简单的员工信息管理系统，可以添加、删除、查找、修改和显示所有员工的信息。它使用了ArrayList来存储所有员工的信息，使用Scanner来读取用户输入。你可以根据自己的需求修改它。