Javaweb期末大作业游戏购物网站

package com.shop.servlet; import com.shop.entity.User; import com.shop.utils.DBUtils; import com.shop.utils.GsonUtil; 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 java.io.IOException; import java.math.BigDecimal; import java.util.ArrayList; import java.util.Arrays; import java.util.List; import java.util.Map; @WebServlet(urlPatterns = "/car") public class CarServlet extends HttpServlet { @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { req.setCharacterEncoding("UTF-8"); resp.setCharacterEncoding("UTF-8"); String method = req.getParameter("method"); if ("update".equals(method)) { update(req, resp); } else if ("list".equals(method)) { list(req, resp); } } private void update(HttpServletRequest request, HttpServletResponse response) { String idStr = request.getParameter("id"); Integer id = null; if (idStr != null && !"".equals(idStr)) { id = Integer.valueOf(idStr); } String shopName = request.getParameter("shopName"); BigDecimal price = null; if (request.getParameter("price")!= null) { price = new BigDecimal(request.getParameter("price")); } String shuliang = request.getParameter("shuliang"); String img = request.getParameter("img"); // 更新 if (id != null) { DBUtils.executeUpdate("update car set shuliang = ? where id = ?", Arrays.asList(shuliang, id)); DBUtils.executeUpdate("delete from car where shuliang = 0", new ArrayList<>()); try { response.getWriter().write("success"); } catch (IOException e) { e.printStackTrace(); } } else { Integer userId = Integer.valueOf(request.getParameter("userId")); List<Map<String, Object>> maps = DBUtils.executeQuery("select * from car where shopName = ? and userId = ?", Arrays.asList(shopName, userId)); if (maps != null && maps.size() > 0) { DBUtils.executeUpdate("update car set shuliang = shuliang + 1 where userId = ? and shopName = ?", Arrays.asList(userId, shopName)); } else { DBUtils.executeUpdate("insert into car(shopName, price, shuliang, img, userId) value(?,?,?,?,?)", Arrays.asList(shopName, price, shuliang, img, userId)); try { response.getWriter().write("success"); } catch (IOException e) { e.printStackTrace(); } } } } private void list(HttpServletRequest request, HttpServletResponse response) { Integer userId = Integer.valueOf(request.getParameter("userId")); List<Map<String, Object>> maps = DBUtils.executeQuery("select * from car where userId = ?", Arrays.asList(userId)); try { response.getWriter().write(GsonUtil.getResponseString(maps)); } catch (IOException e) { e.printStackTrace(); } } }