商品管理功能涉及核心数据模型与多层业务逻辑处理，以下为关键实现细节。 数据模型定义 商品类别实体类采用标准JavaBean规范：

package com.example.domain;

public class ProductCategory {
    private int categoryId;
    private String categoryName;
    
    public int getCategoryId() { return categoryId; }
    public void setCategoryId(int id) { this.categoryId = id; }
    public String getCategoryName() { return categoryName; }
    public void setCategoryName(String name) { this.categoryName = name; }
    
    @Override
    public String toString() {
        return "Category [id=" + categoryId + ", name=" + categoryName + "]";
    }
}

商品主实体类包含完整业务属性：

package com.example.domain;

public class Product {
    private int productId;
    private String productName;
    private double unitPrice;
    private int categoryCode;
    private String categoryName;
    private int stockQuantity;
    private String imageUrl;
    private String description;
    
    // 省略getter/setter及toString方法
}

文件上传处理逻辑 Web层实现文件上传与表单验证，采用Apache Commons FileUpload组件：

package com.example.controller;

import org.apache.commons.fileupload.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;

public class ProductUploadHandler extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 配置上传参数
        DiskFileItemFactory factory = new DiskFileItemFactory(1024 * 1024, new File(getServletContext().getRealPath("/temp")));
        ServletFileUpload upload = new ServletFileUpload(factory);
        upload.setFileSizeMax(1024 * 1024); // 单文件1MB
        upload.setHeaderEncoding("UTF-8");
        
        // 解析表单
        Map<String, String> formData = new HashMap<>();
        String fileSavePath = null;
        
        try {
            List<FileItem> items = upload.parseRequest(req);
            for (FileItem item : items) {
                if (item.isFormField()) {
                    formData.put(item.getFieldName(), item.getString("UTF-8"));
                } else {
                    // 生成安全文件名
                    String originalName = item.getName();
                    String safeName = UUID.randomUUID().toString() + "_" + 
                                     originalName.substring(originalName.lastIndexOf('.') + 1);
                    
                    // 创建存储路径
                    String storagePath = getServletContext().getRealPath("/uploads") + 
                                        File.separator + safeName;
                    new File(storagePath).getParentFile().mkdirs();
                    
                    // 保存文件
                    item.write(new File(storagePath));
                    fileSavePath = "/uploads/" + safeName;
                }
            }
        } catch (FileUploadException e) {
            throw new ServletException("文件上传失败", e);
        }
        
        // 业务处理
        Product product = new Product();
        product.setProductName(formData.get("productName"));
        product.setUnitPrice(Double.parseDouble(formData.get("price")));
        product.setCategoryName(formData.get("categoryName"));
        product.setImageUrl(fileSavePath);
        // ...其他属性设置
        
        ProductService service = ServiceFactory.getInstance(ProductService.class);
        boolean success = service.addProduct(product);
        resp.getWriter().write(success ? "添加成功" : "添加失败");
    }
}

业务逻辑处理 服务层实现商品与类别的关联管理：

package com.example.service;

public class ProductService {
    private ProductDao productDao;
    
    public boolean addProduct(Product product) {
        int categoryId = productDao.getCategoryId(product.getCategoryName());
        if (categoryId == -1) {
            categoryId = productDao.createCategory(product.getCategoryName());
        }
        product.setCategoryCode(categoryId);
        return productDao.saveProduct(product);
    }
}

数据访问层实现 DAO层使用JDBC执行数据库操作：

package com.example.dao;

public class ProductDaoImpl implements ProductDao {
    @Override
    public int getCategoryId(String name) {
        try (Connection conn = DBUtil.getConnection();
             PreparedStatement ps = conn.prepareStatement("SELECT id FROM categories WHERE name = ?")) {
            ps.setString(1, name);
            try (ResultSet rs = ps.executeQuery()) {
                return rs.next() ? rs.getInt(1) : -1;
            }
        } catch (SQLException e) {
            throw new DataAccessException("查询类别失败", e);
        }
    }
    
    @Override
    public boolean saveProduct(Product product) {
        try (Connection conn = DBUtil.getConnection();
             PreparedStatement ps = conn.prepareStatement(
                 "INSERT INTO products (name, price, category_id, stock, image_url, desc) VALUES (?, ?, ?, ?, ?, ?)")) {
            ps.setString(1, product.getProductName());
            ps.setDouble(2, product.getUnitPrice());
            ps.setInt(3, product.getCategoryCode());
            ps.setInt(4, product.getStockQuantity());
            ps.setString(5, product.getImageUrl());
            ps.setString(6, product.getDescription());
            return ps.executeUpdate() > 0;
        } catch (SQLException e) {
            throw new DataAccessException("保存商品失败", e);
        }
    }
}

配置文件示例：

ProductService=com.example.service.ProductServiceImpl
ProductDao=com.example.dao.ProductDaoImpl