Java简单的订餐系统（附系统代码）

一、简介

        本项目是个Java开发的简单的外卖订餐系统（未使用数据库）。

        实现的功能：注册、登录、点餐、查看历史订单、余额充值及优惠券，并将数据写入本地文件。

二、大致过程

1、首先设计登录及注册功能，涉及管理员和用户，其中管理员是账号、密码都为admin的用，使用字节流将账号和密码写入本地文件，根据登录时不同的用户，展示不同的界面。

用户界面

 管理员界面

代码

Admin类

package com.order;

import java.io.*;
import java.util.*;
import java.util.function.BiConsumer;

public class Admin extends User{
    //更新user文件
    public void userWriter(Map<String, String> accountMap) throws IOException {
        OutputStream outputStream = new FileOutputStream(OrderSystem.path+"user.txt");
        Iterator<Map.Entry<String, String>> iterator = accountMap.entrySet().iterator();
        while (iterator.hasNext()){
            String account = iterator.next().getKey();
            String psw = accountMap.get(account);
            outputStream.write((account+","+psw+"\n").getBytes());
        }
        outputStream.close();
    }
    //删除User
    public Map<String, String> deleteUser(Map<String, String> accountMap) throws IOException {
        System.out.print("请输入要删除的用户名:");
        Scanner scanner = new Scanner(System.in);
        String name = scanner.nextLine();
        accountMap.remove(name);
        userWriter(accountMap);
        return accountMap;

    }
    //读取user
    public Map<String, String> loadAccountMap() throws IOException {
        InputStream inputStream = new FileInputStream(OrderSystem.path+"user.txt");
        Map<String, String> accountMap = new HashMap<>();
        InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
        BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
        String line;
        while ((line = bufferedReader.readLine())!=null){
            String[] strings = line.split(",");
            accountMap.put(strings[0],strings[1]);
        }
        inputStream.close();
        return accountMap;
    }
    //更新Food
    public void foodWriter(Map<Integer, Food> foodMap) throws IOException {
        OutputStream outputStream = new FileOutputStream(OrderSystem.path+"food.txt");
        ObjectOutputStream objectOutputStream = new ObjectOutputStream(outputStream);
        objectOutputStream.writeObject(foodMap);
        objectOutputStream.close();
    }
    //添加Food
    public Map<Integer, Food> addFood(Map<Integer, Food> foodMap) throws IOException, ClassNotFoundException {
        Scanner scanner = new Scanner(System.in);

        foodMap.forEach(new BiConsumer<Integer, Food>() {
            @Override
            public void accept(Integer integer, Food food) {
                System.out.println(integer+"\t"+food.getName()+"\t"+food.getPrice());
            }
        });
        System.out.println("--------------");
        System.out.print("输入菜品名称:");
        String name = scanner.nextLine();
        System.out.print("输入菜品价格:");
        int price = scanner.nextInt();
        foodMap.put(foodMap.size()+1,new Food(name,price));
        foodWriter(foodMap);
        return foodMap;
    }
    //读取Food
    public Map<Integer, Food> foodReader() throws IOException, ClassNotFoundException {
        InputStream inputStream = new FileInputStream(OrderSystem.path+"food.txt");
        ObjectInputStream objectInputStream = new ObjectInputStream(inputStream);
        Object object = objectInputStream.readObject();
        objectInputStream.close();
        Map map = (Map) object;
        return map;
    }
    //更改价格
    public Map<Integer, Food> changePrice(Map<Integer, Food> foodMap) throws IOException {
        new User().selectFood(foodMap);
        Scanner scanner = new Scanner(System.in);
        System.out.print("更改价格的菜品编号");
        Integer num = scanner.nextInt();
        if (!foodMap.containsKey(num)){
            System.out.println("编号不存在");
            return foodMap;
        }
        System.out.print("更改价格为:");
        Integer price = scanner.nextInt();
        Food food = foodMap.get(num);
        food.setPrice(price);
        foodMap.put(num,food);
        foodWriter(foodMap);
        return foodMap;

    }
    //更改密码
    public Map<String, String> changePassword(Map<String, String> accountMap) throws IOException {
        Scanner scanner = new Scanner(System.in);
        System.out.print("输入账号:");
        String account0 = scanner.nextLine();
        System.out.print("将密码更改为:");
        String psw0 = scanner.nextLine();
        accountMap.put(account0,psw0);
        userWriter(accountMap);
        return accountMap;
    }



    public void getUser(Map<String, String> accountMap){
        System.out.println("账号\t\t|密码");
        accountMap.forEach(new BiConsumer<String, String>() {
            @Override
            public void accept(String s, String s2) {
                System.out.println(s+"\t\t|"+s2);
            }
        });
    }

    public void main0(Map<String,String> accountMap,Map<Integer,Food> foodMap) throws IOException, ClassNotFoundException { ArrayList list = new ArrayList();
        //管理员界面
        Scanner scanner = new Scanner(System.in);
        int select1 = -1;
        while (select1 != 0){
            Menu.adminMenu();
            select1 = scanner.nextInt();
            switch (select1){
                case 0:
                    //0---退出系统
                    System.exit(0);
                    break;
                case 1:
                    //1---添加用户
                    register(accountMap);
                    break;
                case 2:
                    //2---删除用户
                    accountMap = deleteUser(accountMap);
                    break;
                case 3:
                    //3---添加菜品
                    foodMap = addFood(foodMap);
                    break;
                case 4:
                    //4---查看用户
                    getUser(accountMap);
                    break;
                case 5:
                    //5---修改密码
                     changePassword(accountMap);
                    break;
                case 6:
                    //6---修改菜价
                    changePrice(foodMap);
                    break;
                case 7:
                    //7---查询菜品
                    new User().selectFood(foodMap);
                    break;
                default:
                    System.out.println("输入错误请重新输入");

            }

        }
    }
}

 Food类

package com.order;

import java.io.Serializable;
import java.util.*;

public class Food implements Serializable {
    private String name;
    private int price;
    public Food(String name, int price) {
        this.name = name;
        this.price = price;
    }

    @Override
    public String toString() {
        return name+"\t"+price;
    }

    public String getName() {
        return name;
    }

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

    public int getPrice() {
        return price;
    }

    public void setPrice(int price) {
        this.price = price;
    }
}

Menu类

package com.order;

public class Menu {
    public static void adminMenu(){
        System.out.println("----------------------");
        System.out.println("0---退出系统");
        System.out.println("1---添加用户");
        System.out.println("2---删除用户");
        System.out.println("3---添加菜品");
        System.out.println("4---查看用户");
        System.out.println("5---修改密码");
        System.out.println("6---修改菜价");
        System.out.println("7---查询菜品");
        System.out.println("----------------------");
        System.out.printf("请选择功能：");
    }
    public static void userMenu(){
        System.out.println("----------------------");
        System.out.println("0---退出系统");
        System.out.println("1---点餐");
        System.out.println("2---下单");
        System.out.println("3---查看历史订单");
        System.out.println("4---领取优惠券");
        System.out.println("5---查看优惠券");
        System.out.println("6---查看菜品");
        System.out.println("7---查看余额");
        System.out.println("8---充值余额");
        System.out.println("----------------------");
        System.out.printf("请选择功能：");
    }
}

User类

package com.order;

import java.io.*;
import java.util.*;
import java.util.function.BiConsumer;


public class User implements Serializable{
    private String account;
    private transient String password;
    //优惠券Map<优惠金额,数量>
    private Map<Integer,Integer> discountCard = new HashMap<>();
    //订单表Map<订单号,Map<菜品编号,价格>>
    private Map<Integer,Map<Integer, Integer>> orderMap = new HashMap<>();
    //余额
    private double balance;
    //优惠金额
    private int discount;
    //返回优惠券表
    public Map<Integer,Integer> getDiscountCard() {
        return discountCard;
    }
    //充值余额
    public void recharge(double d){
        this.setBalance(this.balance+d);
    }
    //输出优惠券表
    public void printDiscountCard(){
        if (this.discountCard.isEmpty()){
            System.out.println("无优惠券");
            return;
        }
        System.out.println("优惠金额\t|数量");
        Iterator<Map.Entry<Integer,Integer>> iterator = this.discountCard.entrySet().iterator();
        while(iterator.hasNext()){
            Map.Entry<Integer,Integer> entry = iterator.next();
            System.out.println(entry.getKey()+"\t\t|"+entry.getValue());
        }
    }
    //领取优惠券
    public void setDiscountCard(LinkedList<User> list) {
        Random random = new Random();
        int p = random.nextInt(5)+1;
        System.out.println("获得一张"+p+"元优惠券!");

        if (this.discountCard.containsKey(p)){
            this.discountCard.put(p,this.discountCard.get(p)+1);
        }else{
            this.discountCard.put(p,1);
        }
        //list.add(this);

    }
    //登录
    public int login(Map<String, String> account, int count) throws InterruptedException {
        int c = 0;
        if (account.containsKey(this.account)&&account.get(this.account).equals(this.password)){
            if (this.account.equals("admin")){
                System.out.println("管理员登录成功");
                return 2;
            }else {
                System.out.println("登录成功");
                return 1;
            }

        }else{
            return 0;
        }
    }
    //注册
    public void register(Map<String, String> accountMap) throws IOException {
        OutputStream outputStream = new FileOutputStream(OrderSystem.path+"user.txt",true);
        System.out.println("注册功能:");
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入");
        System.out.print("账号:");
        String uName = scanner.nextLine();
        System.out.print("密码:");
        String psw = scanner.nextLine();
        if (accountMap.containsKey(uName)){
            System.out.println("用户名已存在!");
        }else{
            for (int i = 0; i < OrderSystem.MAX_User; i++) {
                if (!accountMap.containsKey(i)){
                    accountMap.put(uName,psw);
                }
            }

            outputStream.write((uName+","+psw+"\n").getBytes());
        }
    }
    //查询菜品
    public void selectFood(Map<Integer,Food> foodMap){
        System.out.println("菜品编号\t|菜品名称\t|价格");
        foodMap.forEach(new BiConsumer<Integer, Food>() {
            @Override
            public void accept(Integer integer, Food food) {
                System.out.println(integer+"\t\t|"+food.getName()+"\t|"+food.getPrice());
            }
        });
    }
    //点餐
    public void orderFood(Map<Integer,Food> foodMap,Map<Integer, Integer> shopMap){
        //点餐
        //菜品编号
        Scanner scanner = new Scanner(System.in);
        int num;
        System.out.print("请输入菜品编号:");
        num = scanner.nextInt();
        //校验编号是否合法
        while(!foodMap.containsKey(num)){
            if (!foodMap.containsKey(num)){
                System.out.println("编号不存在,请重新输入");
            }
            num = scanner.nextInt();
        }
        //购买数量
        int amount = 0;
        //校验数量是否合法
        while(amount<=0){
            System.out.printf("请输入购买数量:");
            amount = scanner.nextInt();
            if (amount<=0){
                System.out.println("输入错误，请重新输入");
            }
        }
        //购物车中存在相同商品将数量相加
        if (shopMap.containsKey(num)){
            shopMap.put(num,shopMap.get(num)+amount);
        }else {
            shopMap.put(num,amount);
        }
        System.out.println("菜品名称\t|数量\t|价格");
        //创建迭代器
        Iterator<Map.Entry<Integer,Integer>> orderIterator = shopMap.entrySet().iterator();
        Map.Entry<Integer,Integer> orderEntry ;
        Integer sumPrice = 0;
        String name = null;
        Integer count = null;
        Integer price = null;
        //迭代器循环
        while (orderIterator.hasNext()){
            orderEntry = orderIterator.next();
            //通过food类中的foodMap获取编号对应的名称
            name = foodMap.get(orderEntry.getKey()).getName();
            //数量
            count = orderEntry.getValue();
            //价格=单价*数量
            price = foodMap.get(orderEntry.getKey()).getPrice()*count;
            sumPrice +=price;
            System.out.println(name+"\t|"+count+"\t\t|"+price);
        }
        System.out.println("总价:"+sumPrice);
    }
    //输出历史订单
    public void getOrder(Map<Integer,Food> foodMap,int num){

        Integer sumPrice = 0;
        String name = null;
        Integer count = null;
        Integer price = null;
        //遍历历史订单并输出
        for (int i = num; i < this.orderMap.size(); i++) {
            System.out.println("----------------------");
            System.out.println("订单号:"+i);
            Iterator<Map.Entry<Integer, Integer>> orderIterator = this.orderMap.get(i).entrySet().iterator();
            Map.Entry<Integer,Integer> orderEntry ;
            //迭代器循环
            while (orderIterator.hasNext()){
                orderEntry = orderIterator.next();
                //通过food类中的foodMap获取编号对应的名称
                name = foodMap.get(orderEntry.getKey()).getName();
                //数量
                count = orderEntry.getValue();
                //价格=单价*数量
                price = foodMap.get(orderEntry.getKey()).getPrice()*count;
                sumPrice +=price;
                System.out.println(name+"\t|"+count+"\t\t|"+price);
            }
            System.out.println("总价:"+sumPrice);
            sumPrice = 0;
            System.out.println("----------------------");
        }
    }
    //下单
    public void placeOrder(Map<Integer,Food> foodMap,Map<Integer, Integer> shopMap,LinkedList<User> list) throws IOException {
        if (shopMap.isEmpty()){
            System.out.println("订单为空请重新点餐");
            return;
        }

        Map<Integer, Integer> sMap = new HashMap<>();
        //拷贝购物车
        sMap.putAll(shopMap);
        int sum = 0;

        Iterator<Map.Entry<Integer,Integer>> iterator = shopMap.entrySet().iterator();
        Map.Entry<Integer,Integer> orderEntry ;

        while (iterator.hasNext()){
            orderEntry = iterator.next();
            //总价+=单价*数量
            sum += foodMap.get(orderEntry.getKey()).getPrice()*orderEntry.getValue();
        }
        Scanner scanner = new Scanner(System.in);
        //输出优惠券
        this.printDiscountCard();
        if (!this.discountCard.isEmpty()){
            System.out.println("是否使用优惠券");
            System.out.println("0---否");
            System.out.println("1---是");
            int select = -1;
            while(!(select==0 || select==1)){
                select = scanner.nextInt();
                switch (select){
                    case 0:
                        this.discount = 0;
                        break;
                    case 1:
                        System.out.print("请输入你要使用的优惠券金额为:");
                        this.discount = scanner.nextInt();
                        //存在该金额，数量-1
                        if (this.discountCard.containsKey(discount)){
                            this.discountCard.put(discount,this.discountCard.get(discount)-1);
                            if (this.discountCard.get(discount)==0){
                                this.discountCard.remove(discount);
                            }
                        }
                        break;
                    default:
                        System.out.println("输入错误,请重新输入");
                }
            }
        }



        sum -=discount;
        if (this.balance<sum){
            System.out.println("余额不足，请重新下单。当前余额:"+this.balance);
            shopMap.clear();
            return;
        }
        this.setBalance(this.balance-sum);
        orderMap.put(orderMap.size(), sMap);
        shopMap.clear();

        this.getOrder(foodMap,orderMap.size()-1);
        System.out.println("优惠:"+discount);
        System.out.println("支付:"+sum);
        System.out.println("----------------------");
        //将登录的user添加进list
        //list.add(this);
        //System.out.println("历史订单查询完毕");
    }
    //读取uuser
    public LinkedList<User> listReader() throws IOException, ClassNotFoundException {
        InputStream inputStream = new FileInputStream(OrderSystem.path+"uuser.txt");
        ObjectInputStream objectInputStream = new ObjectInputStream(inputStream);
        Object object = objectInputStream.readObject();
        objectInputStream.close();
        LinkedList<User> list = (LinkedList<User>) object;
        return list;
    }
    //更新文件
    public void listWriter(LinkedList<User> list) throws IOException {
        list.add(this);
        OutputStream outputStream = new FileOutputStream(OrderSystem.path+"uuser.txt");
        ObjectOutputStream objectOutputStream = new ObjectOutputStream(outputStream);
        objectOutputStream.writeObject(list);
        objectOutputStream.close();
        list.remove(this);
    }
    //主方法
    public void main(Map<Integer,Food> foodMap,Map<Integer, Integer> shopMap,LinkedList<User> list) throws IOException, InterruptedException {
        Menu.userMenu();
        for (int i = 0; i < list.size(); i++) {
            if (list.get(i).equals(this)){
                //如果文件中存在同名user，把该user的历史订单拷贝
                this.orderMap.putAll(list.get(i).getOrderMap());
                this.discountCard.putAll(list.get(i).getDiscountCard());
                this.setBalance(list.get(i).getBalance());
                list.remove(i);
                break;
            }
        }

        Scanner scanner = new Scanner(System.in);
        int  select = scanner.nextInt();
        switch (select){
            case 0:
                //0---退出系统
                System.exit(0);

                break;
            case 1:
                //1---点餐
                orderFood(foodMap,shopMap);
                break;
            case 2:
                //2---下单
                placeOrder(foodMap,shopMap,list);
                //list.add(this);
                this.listWriter(list);
                break;
            case 3:
                //3---查看历史订单
                this.getOrder(foodMap,0);
                break;
            case 4:
                //4---领取优惠券
                this.setDiscountCard(list);
                //更新文件
                this.listWriter(list);
                break;
            case 5:
                //5---查看优惠券
                this.printDiscountCard();
                break;
            case 6:
                //6---查看菜品
                selectFood(foodMap);
                break;
            case 7:
                //7---查看余额
                System.out.println("余额:"+this.getBalance());
                break;
            case 8:
                //8---充值余额
                System.out.print("输入要充值的金额:");
                double money = scanner.nextDouble();
                Thread.sleep(500);
                this.recharge(money);
                //更新文件
                this.listWriter(list);
                System.out.println("充值成功,当前余额:"+this.getBalance());
                break;
            default:
                System.out.println("输入错误请重新输入");
        }
    }

    @Override
    public boolean equals(Object o) {
        User u = (User)o;
        if (u.getAccount().equals(this.getAccount())){
            return true;
        }else {
            return false;
        }
    }

    @Override
    public int hashCode() {
        return Objects.hash(account, password);
    }

    public User() {

    }

    public User(String account,String password){
        this.account=account;
        this.password=password;
    }

    public String getAccount() {
        return account;
    }

    public void setAccount(String account) {
        this.account = account;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public Map<Integer, Map<Integer, Integer>> getOrderMap() {
        return orderMap;
    }

    public void setOrderMap(Map<Integer, Map<Integer, Integer>> orderMap) {
        this.orderMap = orderMap;
    }

    public double getBalance() {
        return balance;
    }

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

OrderSystem类

package com.order;


import java.io.*;
import java.util.*;


public class OrderSystem {
    //最大存储量
    public static int MAX_User = 99;
    //文件路径
    public static String path = "D:\\01Buka\\Java394\\src\\com\\order\\";

    public static void main(String[] args) throws InterruptedException, IOException, ClassNotFoundException {

        //账户表account(账号,密码)
        Map<String, String> accountMap = new Admin().loadAccountMap();
        //购物车shopMap
        Map<Integer, Integer> shopMap = new HashMap<>();
        //用户表list(账号,订单表)
        LinkedList<User> list = new User().listReader();
        //LinkedList<User> list = new LinkedList<>();
        //菜谱表
        Map<Integer, Food> foodMap  = new Admin().foodReader();
        //未将序列化文件写入本地之前，需要将上面这行代码注释，运行下面这行代码;若已将序列化文件写入本地，则反之
        //FileReader fileReader = new FileReader(path+"user.txt");
        InputStream inputStream = new FileInputStream(path+"user.txt");
        InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
        BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
        //FileWriter fileWriter = new FileWriter(path+"user.txt");
        OutputStream outputStream = new FileOutputStream(path+"user.txt",true);
        Scanner scanner = new Scanner(System.in);

        User user = null;

        boolean flag = true;
        int select = 0;
        while (flag){
            System.out.println("----------------------");
            System.out.println("0---注册");
            System.out.println("1---登录");
            System.out.println("----------------------");
            System.out.print("请选择功能：");
            select = scanner.nextInt();
            switch (select){
                case 0:{
                    new User().register(accountMap);
                break;
                }
                case 1:{
                    Scanner scanner0 = new Scanner(System.in);
                    String account;
                    String password;
                    int log = 0;
                    for (int i = 0; i < 3; i++) {
                        System.out.println("登录功能:");
                        System.out.println("请输入");
                        System.out.print("账号:");
                        account = scanner0.nextLine();
                        System.out.print("密码:");
                        password = scanner0.nextLine();
                        user = new User(account,password);
                        log = user.login(accountMap,0);

                        if (log == 0){
                            System.out.println("用户名不存在或密码错误");
                        }else {
                            break;
                        }
                        if (i == 2){
                            System.out.println("等待10s重试");
                            Thread.sleep(10000);
                            i=0;
                        }
                    }
                    if (log == 2){
                        //管理员界面
                        new Admin().main0(accountMap,foodMap);
                    }else if (log== 1){
                        //用户界面
                        System.out.println("用户界面");
                        //orderMap = user.loadUserOrder();
                        while (flag){
                            user.main(foodMap, shopMap,list);
                        }
                    }else if (log== 0){
                        System.out.println("登录失败");
                        System.exit(0);
                    }
                    flag = false;
                    break;
                }
                default:
                    System.out.println("输入错误请重新输入");

            }
        }


    }
}