用java实现一个库存管理系统

这里提供一个简单的Java库存管理系统示例，主要包括库存管理、入库、出库和查询功能：

import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class InventoryManagementSystem {
    private static Map<String, Integer> inventory = new HashMap<>();

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        while (true) {
            System.out.println("请选择操作：1-库存管理，2-入库，3-出库，4-查询，0-退出");
            int choice = scanner.nextInt();
            switch (choice) {
                case 1:
                    manageInventory();
                    break;
                case 2:
                    stockIn();
                    break;
                case 3:
                    stockOut();
                    break;
                case 4:
                    checkInventory();
                    break;
                case 0:
                    System.out.println("感谢使用，再见！");
                    System.exit(0);
                default:
                    System.out.println("输入有误，请重新输入！");
            }
        }
    }

    private static void manageInventory() {
        Scanner scanner = new Scanner(System.in);
        while (true) {
            System.out.println("请选择操作：1-添加商品，2-删除商品，0-返回上级菜单");
            int choice = scanner.nextInt();
            switch (choice) {
                case 1:
                    System.out.println("请输入商品名称：");
                    String name = scanner.next();
                    System.out.println("请输入商品数量：");
                    int quantity = scanner.nextInt();
                    if (inventory.containsKey(name)) {
                        System.out.println("该商品已存在，无法添加！");
                    } else {
                        inventory.put(name, quantity);
                        System.out.println("添加成功！");
                    }
                    break;
                case 2:
                    System.out.println("请输入商品名称：");
                    name = scanner.next();
                    if (inventory.containsKey(name)) {
                        inventory.remove(name);
                        System.out.println("删除成功！");
                    } else {
                        System.out.println("该商品不存在，无法删除！");
                    }
                    break;
                case 0:
                    return;
                default:
                    System.out.println("输入有误，请重新输入！");
            }
        }
    }

    private static void stockIn() {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入商品名称：");
        String name = scanner.next();
        if (inventory.containsKey(name)) {
            System.out.println("请输入入库数量：");
            int quantity = scanner.nextInt();
            inventory.put(name, inventory.get(name) + quantity);
            System.out.println("入库成功！");
        } else {
            System.out.println("该商品不存在，无法入库！");
        }
    }

    private static void stockOut() {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入商品名称：");
        String name = scanner.next();
        if (inventory.containsKey(name)) {
            System.out.println("请输入出库数量：");
            int quantity = scanner.nextInt();
            int currentQuantity = inventory.get(name);
            if (quantity > currentQuantity) {
                System.out.println("出库失败，库存不足！");
            } else {
                inventory.put(name, currentQuantity - quantity);
                System.out.println("出库成功！");
            }
        } else {
            System.out.println("该商品不存在，无法出库！");
        }
    }

    private static void checkInventory() {
        if (inventory.isEmpty()) {
            System.out.println("库存为空！");
        } else {
            System.out.println("当前库存如下：");
            for (String name : inventory.keySet()) {
                int quantity = inventory.get(name);
                System.out.println(name + "：" + quantity);
            }
        }
    }
}

这个示例中，使用了Java中的Map来存储商品名称和数量信息，实现了基本的库存管理、入库、出库和查询功能，具体操作可以根据需要进行修改和扩展。