使用Java来做一个能够有正常功能的饭卡管理系统

一个饭卡管理系统可以包括以下功能：

1. 管理员登录：管理员需要输入用户名和密码才能登录系统。
2. 饭卡信息管理：管理员可以添加、删除和修改饭卡信息，例如饭卡号码、持卡人姓名、余额等。
3. 消费记录管理：系统需要记录每次使用饭卡的消费记录，包括时间、金额、消费类型等信息。
4. 充值功能：持卡人可以通过管理员或自助充值机来给自己的饭卡充值。
5. 查询功能：持卡人和管理员都可以查询饭卡的余额、消费记录等信息。

以下是一个使用 Java 实现的简单的饭卡管理系统的示例代码。

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

public class MealCardManagementSystem {

    static Scanner scanner = new Scanner(System.in);
    static ArrayList<MealCard> mealCards = new ArrayList<>();

    public static void main(String[] args) {
        System.out.println("Welcome to Meal Card Management System!");

        // 添加测试数据
        mealCards.add(new MealCard("100001", "张三", 100));
        mealCards.add(new MealCard("100002", "李四", 50));
        mealCards.add(new MealCard("100003", "王五", 80));

        while (true) {
            System.out.println();
            System.out.println("Please select the operation you want to perform:");
            System.out.println("1. Administrator login");
            System.out.println("2. Cardholder login");
            System.out.println("3. Exit");
            int choice = scanner.nextInt();

            switch (choice) {
                case 1:
                    adminLogin();
                    break;
                case 2:
                    cardholderLogin();
                    break;
                case 3:
                    System.out.println("Goodbye!");
                    System.exit(0);
                    break;
                default:
                    System.out.println("Invalid choice, please try again.");
            }
        }
    }

    // 管理员登录
    static void adminLogin() {
        System.out.println("Please enter your username:");
        String username = scanner.next();
        System.out.println("Please enter your password:");
        String password = scanner.next();

        if (username.equals("admin") && password.equals("123456")) {
            adminMenu();
        } else {
            System.out.println("Wrong username or password, please try again.");
        }
    }

    // 管理员菜单
    static void adminMenu() {
        while (true) {
            System.out.println();
            System.out.println("Please select the operation you want to perform:");
            System.out.println("1. Add a meal card");
            System.out.println("2. Delete a meal card");
            System.out.println("3. Update a meal card");
            System.out.println("4. View all meal cards");
            System.out.println("5. Back to main menu");
            int choice = scanner.nextInt();

            switch (choice) {
                case 1:
                    addMealCard();
                    break;
                case 2:
                    deleteMealCard();
                    break;
                case 3:
                    updateMealCard();
                    break;
                case 4:
                    viewAllMealCards();
                    break;
                case 5:
                    return;
                default:
                    System.out.println("Invalid choice, please try again.");
            }
        }
    }

    // 添加饭卡
    static void addMealCard() {
        System.out.println("Please enter the meal card number:");
        String number = scanner.next();

        // 检查饭卡号是否已存在
        for (MealCard mealCard : mealCards) {
            if (mealCard.getNumber().equals(number)) {
                System.out.println("The meal card number already exists, please try again.");
                return;
            }
        }

        System.out.println("Please enter the cardholder's name:");
        String name = scanner.next();
        System.out.println("Please enter the balance:");
        double balance = scanner.nextDouble();

        MealCard mealCard = new MealCard(number, name, balance);
        mealCards.add(mealCard);

        System.out.println("Add meal card " + number + " success.");
    }

    // 删除饭卡
    static void deleteMealCard() {
        System.out.println("Please enter the meal card number:");
        String number = scanner.next();

        for (MealCard mealCard : mealCards) {
            if (mealCard.getNumber().equals(number)) {
                mealCards.remove(mealCard);
                System.out.println("Delete meal card " + number + " success.");
                return;
            }
        }

        System.out.println("The meal card number does not exist, please try again.");
    }

    // 修改饭卡
    static void updateMealCard() {
        System.out.println("Please enter the meal card number:");
        String number = scanner.next();

        for (MealCard mealCard : mealCards) {
            if (mealCard.getNumber().equals(number)) {
                System.out.println("Please enter the cardholder's name(" + mealCard.getName() + "):");
                String name = scanner.next();
                System.out.println("Please enter the balance(" + mealCard.getBalance() + "):");
                double balance = scanner.nextDouble();

                mealCard.setName(name);
                mealCard.setBalance(balance);

                System.out.println("Update meal card " + number + " success.");
                return;
            }
        }

        System.out.println("The meal card number does not exist, please try again.");
    }

    // 查看所有饭卡
    static void viewAllMealCards() {
        System.out.println("Meal Card Number\tCardholder's Name\tBalance");
        for (MealCard mealCard : mealCards) {
            System.out.println(mealCard.getNumber() + "\t" + mealCard.getName() + "\t" + mealCard.getBalance());
        }
    }

    // 持卡人登录
    static void cardholderLogin() {
        System.out.println("Please enter your meal card number:");
        String number = scanner.next();

        for (MealCard mealCard : mealCards) {
            if (mealCard.getNumber().equals(number)) {
                cardholderMenu(mealCard);
                return;
            }
        }

        System.out.println("The meal card number does not exist, please try again.");
    }

    // 持卡人菜单
    static void cardholderMenu(MealCard mealCard) {
        while (true) {
            System.out.println();
            System.out.println("Please select the operation you want to perform:");
            System.out.println("1. View balance");
            System.out.println("2. View consumption records");
            System.out.println("3. Recharge");
            System.out.println("4. Back to main menu");
            int choice = scanner.nextInt();

            switch (choice) {
                case 1:
                    System.out.println("Your balance is " + mealCard.getBalance() + ".");
                    break;
                case 2:
                    viewConsumptionRecords(mealCard);
                    break;
                case 3:
                    recharge(mealCard);
                    break;
                case 4:
                    return;
                default:
                    System.out.println("Invalid choice, please try again.");
            }
        }
    }

    // 查看消费记录
    static void viewConsumptionRecords(MealCard mealCard) {
        System.out.println("Time\tAmount\tType");
        for (String record : mealCard.getConsumptionRecords()) {
            System.out.println(record);
        }
    }

    // 充值
    static void recharge(MealCard mealCard) {
        System.out.println("Please enter the recharge amount:");
        double amount = scanner.nextDouble();

        mealCard.setBalance(mealCard.getBalance() + amount);
        mealCard.addConsumptionRecord(System.currentTimeMillis(), amount, "Recharge");

        System.out.println("Recharge success, your balance is " + mealCard.getBalance() + ".");
    }

}

class MealCard {

    private String number;
    private String name;
    private double balance;
    private ArrayList<String> consumptionRecords = new ArrayList<>();

    public MealCard(String number, String name, double balance) {
        this.number = number;
        this.name = name;
        this.balance = balance;
    }

    public String getNumber() {
        return number;
    }

    public void setNumber(String number) {
        this.number = number;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public double getBalance() {
        return balance;
    }

    public void setBalance(double balance) {
        this.balance = balance;
    }

    public ArrayList<String> getConsumptionRecords() {
        return consumptionRecords;
    }

    public void addConsumptionRecord(long time, double amount, String type) {
        String record = time + "\t" + amount + "\t" + type;
        consumptionRecords.add(record);
    }

}

这是一个简单的饭卡管理系统，你可以根据需要进行修改和完善。