数据库代码：
create database xiaojungan; use xiaojungan; create table IF NOT EXISTS `t_user` ( `id` int NOT NULL AUTO_INCREMENT, `username` varchar(50) NOT NULL , `password` varchar(50) NULL , `role` int(11) NOT NULL DEFAULT '0' COMMENT '用户角色', PRIMARY KEY (`id`) ) AUTO_INCREMENT=100; CREATE TABLE `t_food` ( `id` int(11) NOT NULL AUTO_INCREMENT, `foodname` varchar(100) NOT NULL, `type_id` int(11) , `descript` longtext , `price` decimal(10,2) , `onSale` int(11) default '0', `imgAddress` varchar(200) , PRIMARY KEY (`id`) ) ; CREATE TABLE `t_type` ( `id` int(11) NOT NULL AUTO_INCREMENT, `typename` varchar(20) , PRIMARY KEY (`id`) ) ; CREATE TABLE `t_order` ( `id` int(11) NOT NULL AUTO_INCREMENT, `food_id` int(11), `user_id` int(11), `table_id` int(11), `food_account` int(11) , PRIMARY KEY (`id`) ); CREATE TABLE `t_table` ( `id` int(11) NOT NULL AUTO_INCREMENT, `tablename` varchar(20) , `user_id` int(11), PRIMARY KEY (`id`) )
c3p0-config.xml
<?xml version="1.0" encoding="UTF-8"?> <c3p0-config> <default-config> <property name="driverClass">com.mysql.cj.jdbc.Driver</property> <property name="jdbcUrl">jdbc:mysql://localhost:3306/xiaojungan?serverTimezone=Asia/Shanghai</property> <property name="user">root</property> <property name="password">147258369</property> <!-- 初始化连接的数量 --> <property name="initialPoolSize">10</property> <!-- 最大空闲时间，单位是秒 --> <property name="maxIdleTime">1</property> <!-- 池中最大连接的数量 --> <property name="maxPoolSize">100</property> <!-- 池中最小连接的数量 --> <property name="minPoolSize">10</property> </default-config> </c3p0-config>
Java
FoodDaoimpl.java
package dao.daoImpl; import bean.Food; import util.C3P0Util; import dao.FoodDao; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.util.ArrayList; import java.util.List; public class FoodDaoImpl implements FoodDao{ @Override public void addFood(Food food) throws Exception{ String sql = "INSERT INTO `xiaojungan`.`t_food`(`foodname`,`type_id`,`descript`,`price`,`saling`,`img`) VALUES (?,?,?,?,?,?)"; try( Connection conn = C3P0Util.getConnection(); PreparedStatement ps = conn.prepareStatement(sql); ) { ps.setString(1,food.getFoodname()); ps.setInt(2, food.getType_id()); ps.setString(3,food.getDescript()); ps.setBigDecimal(4, food.getPrice()); ps.setInt(5,food.getSaling()); ps.setString(6, food.getImg()); ps.executeUpdate(); } catch (Exception e) { e.printStackTrace(); throw new RuntimeException("添加失败！"); } } @Override public List<Food> findSalingFoods() throws Exception{ String sql = "select * from t_food where saling=?"; List<Food> foodList = new ArrayList<>(); try( Connection conn = C3P0Util.getConnection(); PreparedStatement ps = conn.prepareStatement(sql) ) { ps.setInt(1, 1); try ( ResultSet rs = ps.executeQuery() ) { //将查询出的结果数据封装到List对象中 while(rs.next()){ Food b = new Food(); b.setId(rs.getInt("id")); b.setFoodname(rs.getString("foodname")); b.setType_id(rs.getInt("type_id")); b.setDescript(rs.getString("descript")); b.setPrice(rs.getBigDecimal("price")); b.setImg(rs.getString("img")); b.setSaling(rs.getInt("saling")); foodList.add(b); } } catch (Exception e) { e.printStackTrace(); } }catch (Exception e){ e.printStackTrace(); } return foodList; } @Override public Food findFood_id(int id) throws Exception { String sql = "select * from t_food where id=?"; Food b = null; try( Connection conn = C3P0Util.getConnection(); PreparedStatement ps = conn.prepareStatement(sql) ) { ps.setInt(1, id); try ( ResultSet rs = ps.executeQuery() ) { //将查询出的结果数据封装到Food对象中 if(rs.next()){ b = new Food(); b.setId(rs.getInt("id")); b.setFoodname(rs.getString("foodname")); b.setType_id(rs.getInt("type_id")); b.setDescript(rs.getString("descript")); b.setPrice(rs.getBigDecimal("price")); b.setSaling(rs.getInt("saling")); b.setImg(rs.getString("img")); return b; } } catch (Exception e) { e.printStackTrace(); } }catch (Exception e){ e.printStackTrace(); } return b; } }
Html代码
index.html
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>小郡肝</title> <style type="text/css"> #main{ width: 80%;height: auto; margin: 0 auto; overflow:auto; background: burlywood; } #header_div{ width:80%;height: auto; overflow:auto; margin:5px auto 5px; background: coral; border-style: groove; } #header{ width:80%;height: auto; margin:0px auto ; padding: 20px; overflow:auto; } #food_div{ width:80%;height: auto; margin:0px auto 50px auto; overflow:auto; border-style: solid; background: aliceblue; } .childfood_div{ width:80%;height: auto; margin:5px auto ; border-style: solid; padding: 20px; overflow:auto; } </style> </head> <body> <div id="main"> <div id="header_div"> <div id="header"> <span style="font-family: 微软雅黑;font-size: xx-large">小郡肝火锅</span> <br> <p style="float: right"> <span id="loginT"><a href="login.html">登陆</a></span><span> </span> <span id="registT"><a href="register.html">注册</a> </span><span> </span> <span id="order" style="outline: none;"><a href="OrderServlet">餐车</a> </span> </p> </div> </div> <div id="food_div"> </div> </div> </body> <script type="text/javascript" src="MyAjax.js"></script> <script type="text/javascript"> window.onload = function () { var foodDiv = document.getElementById("food_div"); //获取XMLHttpRequest对象 var xhr = getXMLHttpRequest(); var user_id = "" ; //回调函数 xhr.onreadystatechange = function(){ if(xhr.readyState == 4){ if(xhr.status == 200){ var newsJ = xhr.responseText;//获取服务器返回的数据 if(newsJ == ""){ return; } //转化Json消息 var result = JSON.parse(newsJ); if(result[0] != null){ //消息第一个元素为当前用户 var loginT = document.getElementById("loginT"); loginT.innerHTML = result[0].username; user_id = result[0].id; var registT = document.getElementById("registT"); registT.innerHTML = "<a href='LoginOutServlet'>注销</a>"; var order = document.getElementById("order"); order.innerHTML = "<a href='OrderServlet?user_id="+ user_id +"'>餐车</a>"; } var childDivs = ""; //循环放入到div中 for(var i=1; i<result.length; i++){ childDivs += "<br><div class='childfood_div'>" + "<div style='float: left'>" + "<img src='" + result[i].img + "' width='198' height='198'/>" + "</div>" + "<div style='float: left'>" + "<br> " +"<sqan style='font-size: x-large;font-family: 黑体'>" + result[i].foodname + "</sqan>" + "<br><br> " + "在售价：" + result[i].price + "<br><br> " + "<sqan>" +"描述："+ result[i].descript +"</sqan>" + "<sqan>" +"分类："+ result[i].type_id+"</sqan>" + "</div>" + "<div style='float: left'>" + "<br><br><br><br><br><br><br><br> " + "<a href ='AddOrderServlet?food_id=" + result[i].id + "&user_id=" + user_id + "&food_account=1"+ "'>加入餐车</a>" + "</div>" + "</div>"; } //把多个食物childDivs放入列表foodDiv中 foodDiv.innerHTML = childDivs; } } } //创建连接 xhr.open("get","/Servlet?id=food"); //发送请求 xhr.send(null); } </script> </html>