Java商品管理系统开发教程

public class Product {
    private String id;
    private String name;
    private double price;
    private int stock;

    public Product(String id, String name, double price, int stock) {
        this.id = id;
        this.name = name;
        this.price = price;
        this.stock = stock;
    }

    // Getter 和 Setter 方法
    public String getId() { return id; }
    public void setId(String id) { this.id = id; }

    public String getName() { return name; }
    public void setName(String name) { this.name = name; }

    public double getPrice() { return price; }
    public void setPrice(double price) { this.price = price; }

    public int getStock() { return stock; }
    public void setStock(int stock) { this.stock = stock; }

    @Override
    public String toString() {
        return "商品编号：" + id + " | 名称：" + name +
               " | 价格：" + price + "元 | 库存：" + stock + "件";
    }
}

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

public class ProductManager {
    private ArrayList<Product> products = new ArrayList<>();
    private Scanner scanner = new Scanner(System.in);

    public void start() {
        while (true) {
            System.out.println("\n=== 小型商品管理系统 ===");
            System.out.println("1. 添加商品");
            System.out.println("2. 查看所有商品");
            System.out.println("3. 查询商品");
            System.out.println("4. 修改商品");
            System.out.println("5. 删除商品");
            System.out.println("6. 退出");
            System.out.print("请选择操作：");

            int choice = scanner.nextInt();
            scanner.nextLine(); // 消费换行符

            switch (choice) {
                case 1 -> addProduct();
                case 2 -> showAllProducts();
                case 3 -> findProduct();
                case 4 -> updateProduct();
                case 5 -> deleteProduct();
                case 6 -> {
                    System.out.println("系统已退出！");
                    return;
                }
                default -> System.out.println("无效选择，请重试。");
            }
        }
    }

    private void addProduct() {
        System.out.print("请输入商品编号：");
        String id = scanner.nextLine();
        if (findProductById(id) != null) {
            System.out.println("该编号商品已存在！");
            return;
        }

        System.out.print("请输入商品名称：");
        String name = scanner.nextLine();
        System.out.print("请输入价格：");
        double price = scanner.nextDouble();
        System.out.print("请输入库存数量：");
        int stock = scanner.nextInt();
        scanner.nextLine();

        products.add(new Product(id, name, price, stock));
        System.out.println("商品添加成功！");
    }

    private void showAllProducts() {
        if (products.isEmpty()) {
            System.out.println("暂无商品信息。");
        } else {
            for (Product p : products) {
                System.out.println(p);
            }
        }
    }

    private void findProduct() {
        System.out.print("请输入要查询的商品编号：");
        String id = scanner.nextLine();
        Product p = findProductById(id);
        if (p != null) {
            System.out.println("找到商品：" + p);
        } else {
            System.out.println("未找到该商品！");
        }
    }

    private Product findProductById(String id) {
        for (Product p : products) {
            if (p.getId().equals(id)) {
                return p;
            }
        }
        return null;
    }

    private void updateProduct() {
        System.out.print("请输入要修改的商品编号：");
        String id = scanner.nextLine();
        Product p = findProductById(id);
        if (p == null) {
            System.out.println("未找到该商品！");
            return;
        }

        System.out.print("请输入新名称（原：" + p.getName() + "）：");
        String name = scanner.nextLine();
        System.out.print("请输入新价格（原：" + p.getPrice() + "）：");
        double price = scanner.nextDouble();
        System.out.print("请输入新库存（原：" + p.getStock() + "）：");
        int stock = scanner.nextInt();
        scanner.nextLine();

        p.setName(name);
        p.setPrice(price);
        p.setStock(stock);
        System.out.println("商品信息已更新！");
    }

    private void deleteProduct() {
        System.out.print("请输入要删除的商品编号：");
        String id = scanner.nextLine();
        Product p = findProductById(id);
        if (p != null) {
            products.remove(p);
            System.out.println("商品已删除！");
        } else {
            System.out.println("未找到该商品！");
        }
    }

    public static void main(String[] args) {
        new ProductManager().start();
    }
}