校园网站制作/培训网站模板

我们在上面实现了数据库层的代码，现在我们来实现业务层和Servlet层的代码：
业务层的代码如下：

package com.weiyuan.goods.category.service;import java.sql.SQLException;
import java.util.List;import com.weiyuan.goods.category.dao.CategoryDao;
import com.weiyuan.goods.category.domain.Category;public class CategoryService {private CategoryDao dao = new CategoryDao();public  List<Category> findAll(){try {return dao.findAll();} catch (SQLException e) {// TODO Auto-generated catch blockthrow new RuntimeException(e.getMessage());}}
}

我们来看看Servlet层的代码：

package com.weiyuan.goods.category.web.servlet;import java.io.IOException;
import java.util.List;import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import com.weiyuan.goods.category.domain.Category;
import com.weiyuan.goods.category.service.CategoryService;import cn.itcast.servlet.BaseServlet;/*** Servlet implementation class CategoryServlet*/
@WebServlet("/CategoryServlet")
public class CategoryServlet extends BaseServlet {private static final long serialVersionUID = 1L;private CategoryService service = new CategoryService();public String findAll(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stubList<Category> parents = service.findAll();request.setAttribute("parents", parents);//重定向到left.jsp页面return"f:/jsps/left.jsp";}}