案例介绍：
编写一个超市购物程序，在一家超市有牙刷、毛巾、水杯、苹果和香蕉五种商品，用户输入商品序列号进行商品购买，用户输入购买数量后计算出所需要花费的钱，一次购买结束后，需要用户输入“Y”或“N”，“Y”代表继续购买，“N”代表购物结束，此时需要计算并输出本次购物的总计花费的钱。商品价格如下表所示。
运行结果：
完整代码：
import java.util.Scanner;public class supermarket { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); double toothbrush = 8.8;//牙刷 double towel = 10;//毛巾 double cup = 18.8;//水杯 double apple = 12.5;//苹果 double banana =15.5;//香蕉 System.out.println("------------黑马小商城------------"); System.out.println("1.牙刷的价格为："+toothbrush+"元"); System.out.println("2.毛巾的价格为："+towel+"元"); System.out.println("3.水杯的价格为："+cup+"元"); System.out.println("4.苹果的价格为："+apple+"元"); System.out.println("5.香蕉的价格为："+banana+"元"); System.out.println("--------------------------------"); int item;//购买商品序列号 int count;//购买商品的数量 double total = 0;//购买商品总金额 String good = "商品名"; String goods = "商品量词"; double price = 0; String choice = "Y"; do{ System.out.print("请输入您需要购买商品的序列号："); item = scanner.nextInt(); switch (item) { //将序列号对应的商品名、商品量词、商品价格分别赋值给good、goods、price case 1: good = "牙刷"; goods = "把"; price = toothbrush; break; case 2: good = "毛巾"; goods = "条"; price = towel; break; case 3: good = "水杯"; goods = "个"; price = cup; break; case 4: good = "苹果"; goods = "斤"; price = apple; break; case 5: good = "香蕉"; goods = "斤"; price =banana; break; default: item=0;//若序列号输入错误，将item赋值为0 System.out.println("---------商品序列号输入错误---------"); } if(item!=0) //序列号输入正确，执行if语句 { System.out.print("请输入您需要购买" + good + "的数量："); count = scanner.nextInt(); total = total + count * price; System.out.println("您购买了" + good + count + goods + "，需要花费" + count * price + "元"); } System.out.print("需要继续购买请输入Y，否则输入N："); choice = scanner.next(); while(!choice.equals("Y")&&!choice.equals("N"))//若输入字母不为Y或N，则进入while循环 { System.out.println("--------是否继续购买识别失败--------"); System.out.print("需要继续购买请输入Y，否则输入N："); choice = scanner.next(); }//输入"Y"循环继续，输入"N"循环退出 }while(choice.equals("Y")); System.out.println("您本次购物共花费 "+total+" 元"); System.out.println("期待您的下次光临！"); }}来源地址：https://blog.csdn.net/weixin_66697650/article/details/128586708
