第一本书的项目
项目名：吃货联盟订餐系统
package item_one;
import java.util.Scanner;
public class Item_one {
public static void main(String[] args) {
// 数据主体，一组订单信息
String[] names = new String[6];// 订餐人
String[] dishMegs = new String[6];// 所订餐品信息
int[] times = new int[6];// 送餐时间
String[] addresses = new String[6];// 送餐地址
int[] states = new int[6];// 订单状态 0：已预定 1：已完成
double[] sumPrices = new double[6];// 总金额
// 初始化两条订单信息
names[0] = "杨小灿";
dishMegs[0] = "红烧带鱼2份";
times[0] = 12;
addresses[0] = "深圳市福田区";
states[0] = 0;
sumPrices[0] = 76.0;
// 初始化第二条信息
names[1] = "小灿";
dishMegs[1] = "鱼香茄子2份";
times[1] = 12;
addresses[1] = "深圳市福田区";
states[1] = 1;
sumPrices[1] = 45.0;
// 数据主体，一组餐品信息
String[] dishNames = { "红烧带鱼", "鱼香茄子", "时令蔬菜" }; // 菜品名称
double[] prices = new double[] { 38.0, 20.0, 10.0 }; // 菜品单价
int[] praiseNums = new int[3]; // 点赞数
// 二.整体框架
Scanner input = new Scanner(System.in);
int num = -1; // 用户输入0时返回主菜单，否则退出系统
boolean isExit = false; // 标志用户是否退出系统
System.out.println("\n欢迎使用“吃货联盟订餐系统”");
// 循环：显示菜单，根据用户选择相应的数字执行相应的功能
do {
// 显示菜单
System.out.println("******************");
System.out.println("1.我要订餐");
System.out.println("2.查看餐袋");
System.out.println("3.签收订单");
System.out.println("4.删除订单");
System.out.println("5.我要点赞");
System.out.println("6.退出系统");
System.out.println("******************");
System.out.print("请选择：");
int choose = input.nextInt(); // 记录用户选择的功能编号
// 根据用户输入的功能编号，执行相应的功能
// 1
switch (choose) {
case 1:
// 我要订餐
System.out.println("***我要订餐***");
boolean isAdd = false; // 记录是否可以订餐
for (int j = 0; j < names.length; j++) {
if (names[j] == null) {// 找到第一个空位置，可以添加订单信息
isAdd = true; // 置标志位，可以订餐
System.out.print("请输入订餐人姓名：");
String name = input.next();
// 显示供选择的菜品信息
System.out.println("序号" + "\t" + "菜名" + "\t" + "单价" + "\t" + "点赞数");
for (int i = 0; i < dishNames.length; i++) {
String price = prices[i] + "元";
String priaiseNum = (praiseNums[i]) > 0 ? praiseNums[i] + "赞" : "0";
System.out.println((i + 1) + "\t" + dishNames[i] + "\t" + price + "\t" + priaiseNum);
}
// 用户点菜
System.out.print("请选择您要点的菜品编号：");
int chooseDish = input.nextInt();
System.out.print("请选择您要的份数：");
int number = input.nextInt();
String dishMeg = dishNames[chooseDish - 1] + "" + number + "份";
double sumPrice = prices[chooseDish - 1] * number;
// 餐费满50元，免送餐费5元
double deliCharge = (sumPrice >= 50) ? 0 : 5;
System.out.print("请输入送餐时间（送餐时间是10点至20点间整点送餐）：");
int time = input.nextInt();
while (time < 10 || time > 20) {
System.out.print("您输入有误，请输入10-20间的整数！");
time = input.nextInt();
}
System.out.print("请输入送餐地址：");
String address = input.next();
// 无需添加状态，默认是0，即以预定状态
System.out.println("订餐成功！");
System.out.println("您订的是：" + dishMeg);
System.out.println("送餐时间：" + time + "点");
System.out.println("餐费：" + sumPrice + "元" + "送餐费" + deliCharge + "元，总计：" + (sumPrice + deliCharge) + "元");
// 添加数据
names[j] = name;
dishMegs[j] = dishMeg;
times[j] = time;
addresses[j] = address;
sumPrices[j] = sumPrice + deliCharge;
break;
}
}
if (!isAdd) {
System.out.println("对不起，您的餐袋已满！");
}
break;
case 2:
// 查看餐袋
System.out.println("***查看餐袋***");
System.out.println("序号\t订餐人\t餐品信息\t\t送餐时间\t送餐地址\t\t总金额\t订单状态");
for (int i = 0; i < names.length; i++) {
if (names[i] != null) {
String state = (states[i] == 0) ? "已预定" : "已完成";
String date = times[i] + "点";
String sumPrice = sumPrices[i] + "元";
System.out.println((i + 1) + "\t" + names[i] + "\t" + dishMegs[i] + "\t\t" + date + "\t"
+ addresses[i] + "\t" + sumPrice + "\t" + state);
}
}
break;
case 3:
// 签收订单
System.out.println("***签收订单***");
boolean isSignFind = false;// 找到要签收的订单
System.out.print("请选择要签收的订单序号：");
int signOrderId = input.nextInt();
for (int i = 0; i < names.length; i++) {
// 状态为已预定，序号为用户输入的订单序号减1：可签收
// 状态为已完成，序号为用户输入的订单序号减1：不可签收
if (names[i] != null && states[i] == 0 && signOrderId == i + 1) {
states[i] = 1;// 将状态值置为已完成
System.out.println("订单签收成功！");
isSignFind = true;// 标记已找到此订单
} else if (names[i] != null && states[i] == 1 && signOrderId == i + 1) {
System.out.println("您选择的订单已完成签收，不能再次签收！");
isSignFind = true;// 标记已找到此订单
}
}
// 未找到的订单序号：不可签收
if (!isSignFind) {
System.out.println("您选择的订单不存在！");
}
break;
case 4:
// 删除订单
System.out.println("***删除订单***");
boolean isDelFind = false;// 标记是否找到要删除的订单
System.out.print("请选择要删除的订单讯号：");
int delId = input.nextInt();
for (int i = 0; i < names.length; i++) {
// 状态值为已完成，序号值为用户输入的序号减1：可删除
// 状态值为已预定，序号值为用户输入的序号减1：不可删除
if (names[i] != null && states[i] == 1 && delId == i + 1) {
isDelFind = true;// 标记已找到此订单
// 执行删除操作：删除位置后的元素依次前移
for (int j = delId - 1; j < names.length - 1; j++) {
names[j] = names[j + 1];
dishMegs[j] = dishMegs[j + 1];
times[j] = times[j + 1];
addresses[j] = addresses[j + 1];
states[j] = states[j + 1];
sumPrices[j] = sumPrices[j + 1];
}
// 最后一位清空
int endIndex = names.length - 1;
names[endIndex] = null;
dishMegs[endIndex] = null;
times[endIndex] = 0;
addresses[endIndex] = null;
states[endIndex] = 0;
sumPrices[endIndex] = 0;
System.out.println("删除订单成功！");
break;
} else if (names[i] != null && states[i] == 0 && delId == i + 1) {
System.out.println("你选择的订单未签收，不能删除！");
isDelFind = true;// 标记已找到此订单
break;
}
}
// 未找到该序号的订单：不能删除
if (!isDelFind) {
System.out.println("您要删除的订单不存在！");
}
break;
case 5:
// 我要点赞
System.out.println("***我要点赞***");
System.out.println("序号" + "\t" + "菜名" + "\t" + "单价");
for (int i = 0; i < dishNames.length; i++) {
String price = prices[i] + "元";
String priaiseNum = (praiseNums[i] > 0 ? praiseNums[i] + "赞" : "");
System.out.println((i + 1) + "\t" + dishNames[i] + "\t" + price + "\t" + priaiseNum);
}
System.out.print("请选择您要点赞的菜品序号：");
int priaiseNum = input.nextInt();
praiseNums[priaiseNum - 1]++;// 点赞数加1
System.out.println("点赞成功！");
break;
case 6:
// 退出系统
System.out.println("***退出系统***");
System.out.println("谢谢使用！欢迎下次光临!");
break;
default:
// 退出系统
isExit = true;
break;
}
if (!isExit) {
System.out.print("输入0返回：");
num = input.nextInt();
} else {
break;
}
} while (num == 0);
}
}