java基礎項目案例：吃貨聯盟訂餐系統

package org;

import java.util.Scanner;

public class OrderingUtil {
	Scanner input = new Scanner(System.in);

	String[] names = new String[5];// 保存訂餐人姓名
	String[] dishMegs = new String[5];// 保存所選菜品名
	int[] dishNums = new int[5];// 保存所選菜品份數
	int[] times = new int[5];// 保存送餐時間
	String[] addresses = new String[5];// 保存送餐地址
	int[] states = new int[5];// 保存訂單狀態：0表示已預訂，1表示已完成
	double[] sumPrices = new double[5];// 保存訂單的總金額

	int[] praiseNums = new int[5];

	String[] dishNames = { "大盤雞", "幹鍋鴨", "水煮魚", "麻婆豆腐", "油燜大蝦" };
	double[] prices = { 20.0, 25.0, 10.0, 30.0, 20.0 };

	public void init() {
		// 初始化3條訂單信息
		// 第1條
		names[0] = "張三";
		dishMegs[0] = "大盤雞";
		dishNums[0] = 3;
		times[0] = 12;
		addresses[0] = "北京路";
		states[0] = 0;
		sumPrices[0] = 60.0;
		// 第2條
		names[1] = "李四";
		dishMegs[1] = "麻婆豆腐";
		dishNums[1] = 2;
		times[1] = 19;
		addresses[1] = "南京路";
		states[1] = 1;
		sumPrices[1] = 60.0;
		// 第3條
		names[2] = "王五";
		dishMegs[2] = "水煮魚";
		dishNums[2] = 1;
		times[2] = 19;
		addresses[2] = "天津路";
		states[2] = 1;
		sumPrices[2] = 15.0;
	}

	public void display() {
		System.out.println("***查看餐袋***");
		System.out.println("序號\t\t訂餐人\t\t餐品名稱\t\t餐品數量\t\t送餐時間\t\t送餐地址\t\t總金額\t\t訂單狀態");
		for (int i = 0; i < names.length; i++) {
			if (names[i] != null) {
				String state = (states[i] == 0) ? "已預訂" : "已完成";
				System.out.println((i + 1) + "\t\t" + names[i] + "\t\t"
						+ dishMegs[i] + "\t\t" + dishNums[i] + "份" + "\t\t"
						+ times[i] + "\t\t" + addresses[i] + "\t\t"
						+ sumPrices[i] + "元" + "\t\t" + state);
			}
		}
	}

	public void add() {
		System.out.println("***我要訂餐***");
		boolean isAdd = false;// 記錄是否可以點餐
		for (int i = 0; i < names.length; i++) {
			if (names[i] == null) {
				isAdd = false;
				System.out.print("請輸入訂餐人姓名：");
				String name = input.next();
				System.out.println("序號" + "\t\t" + "菜名" + "\t\t" + "單價"
						+ "\t\t" + "點贊數");
				for (int j = 0; j < dishNames.length; j++) {
					System.out.println((j + 1) + "\t\t" + dishNames[j] + "\t\t"
							+ prices[j] + "元" + "\t\t" + praiseNums[j]);
				}
				System.out.print("請選擇您要點的菜品編號：");
				int chooseDish = input.nextInt();
				String dishMeg = dishNames[chooseDish - 1];
				System.out.print("請選擇您需要的份數：");
				int number = input.nextInt();
				System.out.print("請輸入送餐時間（送餐時間是10點至20點間整點送餐）：");
				int time = input.nextInt();
				while (time < 10 || time > 20) {
					System.out.print("您的輸入有誤，請輸入10-20間的整數");
					time = input.nextInt();
				}
				System.out.print("請輸入送餐地址：");
				String address = input.next();
				// 默認可以預定，不用寫訂單狀態
				System.out.println("訂餐成功！");
				System.out.println("您定的是：" + dishNames[chooseDish - 1] + number
						+ "份");
				System.out.println("送餐時間：" + time + "點");
				double sumPrice = prices[chooseDish - 1] * number;// 計算餐費
				double sendMoney = (sumPrice >= 50) ? 0 : 5;// 計算送餐費
				System.out.println("餐費：" + sumPrice + "元，" + "送餐費" + sendMoney
						+ "元，" + "總計：" + (sumPrice + sendMoney) + "元。");
				// 添加數據
				names[i] = name;
				dishMegs[i] = dishMeg;
				times[i] = time;
				dishNums[i] = number;
				addresses[i] = address;
				sumPrices[i] = sumPrice + sendMoney;
				break;
			}
			if (isAdd) {
				System.out.println("對不起，您的餐袋已滿！");
			}
		}
	}

	public void delete() {
		System.out.println("***刪除訂單***");
		boolean isDelFind = false;
		System.out.print("請輸入要刪除的訂單序號：");
		int delID = input.nextInt();
		for (int i = 0; i < names.length; i++) {
			// 根據狀態值判斷能不能刪除，只有已完成的才能刪除
			if (names[i] != null && states[i] == 1 && delID == i + 1) {
				isDelFind = true;
				for (int j = delID - 1; j < names.length - 1; j++) {
					names[j] = names[j + 1];
					dishMegs[j] = dishMegs[j + 1];
					dishNums[j] = dishNums[j + 1];
					times[j] = times[j + 1];
					addresses[j] = addresses[j + 1];
					states[j] = states[j + 1];
					sumPrices[j] = sumPrices[j + 1];
				}
				// 將最後一位清空
				names[names.length - 1] = null;
				dishMegs[names.length - 1] = null;
				dishNums[names.length - 1] = 0;
				times[names.length - 1] = 0;
				addresses[names.length - 1] = null;
				states[names.length - 1] = 0;
				sumPrices[names.length - 1] = 0;
				System.out.println("刪除訂單成功！");
				break;
			} else if (names[i] != null && states[i] == 0 && delID == i + 1) {
				isDelFind = true;
				System.out.println("您選擇的訂單未簽收，不能刪除！");
				break;
			}
		} // 未找到的訂單不能刪除
		if (!isDelFind) {
			System.out.println("您要刪除的訂單不存在！");
		}
	}

	public void sign() {
		System.out.println("***簽收訂單***");
		boolean isSignFind = false;
		System.out.print("請選擇要簽收的訂單序號：");
		int sign = input.nextInt();
		for (int i = 0; i < names.length; i++) {
			if (names[i] != null && states[i] == 0 && sign == i + 1) {
				states[i] = 1;
				System.out.println("訂單簽收成功！");
				isSignFind = true;// 標記已找到的訂單
			} else if (names[i] != null && states[i] == 1 && sign == i + 1) {
				System.out.println("您選擇的訂單已完成簽收，不能再次簽收！");
				isSignFind = true;// 標記已找到的訂單
			}
		}
		if (!isSignFind) {
			System.out.println("您選擇的訂單不存在！");
		}
	}

	public void praise() {
		System.out.println("***我要點贊***");
		// 顯示菜品信息
		System.out.println("序號\t菜名\t單價");
		for (int i = 0; i < dishNames.length; i++) {
			String priaiseNum = (praiseNums[i] > 0) ? praiseNums[i] + "贊" : "";
			System.out.println((i + 1) + "\t" + dishNames[i] + "\t" + prices[i]
					+ "元" + priaiseNum);
		}
		System.out.print("請選擇您要點讚的菜品序號：");
		int number = input.nextInt();
		praiseNums[number - 1]++;
		System.out.println("點贊成功");
	}

	public void startMenu() {
		init();
		/* 實現菜單切換 */
		System.out.println("歡迎使用“吃貨聯盟訂餐系統”");
		int num = 1;// 用戶輸入0返回主菜單否則退出系統
		boolean isExit = false;// 標記用戶是否退出系統，true爲退出
		// 循環控制用戶輸入選擇並執行
		do {
			System.out.println("************************");
			System.out.println("1、我要訂餐");
			System.out.println("2、查看餐袋");
			System.out.println("3、簽收訂單");
			System.out.println("4、刪除訂單");
			System.out.println("5、我要點贊");
			System.out.println("6、退出系統");
			System.out.println("************************");
			System.out.print("請選擇：");
			num = input.nextInt();// 用戶輸入所要選擇進行的操作

			/* 使用switch結構來建立選擇內容 */
			switch (num) {
			case 1:// 我要訂餐
				add();
				break;
			case 2:// 查看訂單
				display();
				break;
			case 3:// 我要簽收
				sign();
				break;
			case 4:// 刪除訂單
				delete();
				break;
			case 5:// 我要點贊
				praise();
				break;
			case 6:// 退出
				isExit = true;
				break;
			default:// 輸入不合法，直接退出
				isExit = true;
				break;
			}
			// 返回主界面
			if (!isExit) {
				System.out.print("輸入0返回：");
				num = input.nextInt();
			} else {
				break;
			}

		} while (num == 0);
		System.out.println("謝謝惠顧，歡迎您再次使用！");
		input.close();

	}

}

package org;
public class OrderingMgr {
	public static void main(String[] args) {
		OrderingUtil od = new OrderingUtil();
		od.startMenu();
		}
}