java库存管理如何保

java库存管理如何保

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

public class Shop{
public static void main(String[] args){
//定义集合，存储的是Laptop类型变量
ArrayList array = new ArrayList();
add(array);

while(true){
int choose = chooseFunction();
switch(choose){
//查看库存清单
case 1:
printArrayList(array);
break;

case 2:
changeCount(array);
break;

case 3:
return;

default:
System.out.println("Sorry,暂时不提供此功能");
break;
}
}
}


public static void changeCount(ArrayList array){
for(int i = 0;i < array.size(); i++){
Laptop b = array.get(i);
Scanner s = new Scanner(System.in);
System.out.print("要修改商品"+b.brand+"的库存是：");
b.count = s.nextInt();
}
}


public static void printArrayList( ArrayList array){
int totalCount = 0;
double totalMoney = 0;

for(int i = 0;i < array.size() ; i++){
//存储集合的时候，集合add(b1) b1 是Name类型变量
//获取的时候，集合get方法，获取出来的是什么
Laptop b = array.get(i);
System.out.println(b.brand+" "+b.size+" "+b.price+" "+b.count);
totalCount += b.count;
totalMoney += b.price*b.count;
}
System.out.println("库存总数："+totalCount);
System.out.println("库存商品总金额："+totalMoney);
}


public static void add(ArrayList array){
Laptop b1 = new Laptop();
Laptop b2 = new Laptop();
Laptop b3 = new Laptop();

b1.brand = "MacBookAir";
b1.size = 13.3 ;
b1.price = 6988.88;
b1.count = 5;

b2.brand = "Thinkpad T450";
b2.size = 14.0 ;
b2.price = 5999.99;
b2.count = 10;

b3.brand = "Asus-FL5800";
b3.size = 15.6 ;
b3.price = 4999.5;
b3.count = 18;

//将laptop变量存到集合中
array.add(b1);
array.add(b2);
array.add(b3);

}


public static int chooseFunction(){
System.out.println("-------------库存管理------------");
System.out.println("1.查看库存清单");
System.out.println("2.修改商品库存数量");
System.out.println("3.退出");
System.out.println("请选择您要使用的功能：");
Scanner ran = new Scanner(System.in);
int number = ran.nextInt();
return number;
}
}
要注意加上 import 引用的类 可以避免编译找不到符号的错误
定义一个名为Laptop的类

public class Laptop{
String brand;//品牌
double size;//尺寸
double price;//价格
int count;//库存数
}
得到的结果是：