写一个基于javaweb的鲜花贩卖系统

这里提供一个基于JavaWeb的简单鲜花贩卖系统的示例，仅供参考。

1. 首先，需要创建一个数据库，用于存储鲜花信息、订单信息等。这里我们创建一个名为 "flower_shop" 的数据库，包含两个表：

- flower 表：包含 flower_id、flower_name、flower_price、flower_image 等字段，用于存储鲜花的信息。
- order 表：包含 order_id、user_id、flower_id、order_time、order_status 等字段，用于存储订单信息。

2. 然后，创建一个 JavaWeb 项目，包含以下文件和目录：

|- src/
|   |- com.example.controller/
|   |   |- FlowerController.java
|   |   |- OrderController.java
|   |- com.example.dao/
|   |   |- FlowerDao.java
|   |   |- OrderDao.java
|   |- com.example.model/
|   |   |- Flower.java
|   |   |- Order.java
|   |- com.example.utils/
|   |   |- DBUtils.java
|- webapp/
|   |- WEB-INF/
|   |   |- views/
|   |   |   |- flower.jsp
|   |   |   |- order.jsp
|   |   |- web.xml
|   |- index.jsp
|   |- login.jsp
|   |- register.jsp
|- pom.xml

3. 在 pom.xml 中添加以下依赖：

<!-- Servlet API -->
<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>javax.servlet-api</artifactId>
    <version>4.0.1</version>
    <scope>provided</scope>
</dependency>

<!-- JSTL -->
<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>jstl</artifactId>
    <version>1.2</version>
</dependency>

<!-- MySQL Connector -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.26</version>
</dependency>

4. 编写 Flower 类和 Order 类，用于存储鲜花信息和订单信息：

package com.example.model;

public class Flower {
    private int flowerId;
    private String flowerName;
    private double flowerPrice;
    private String flowerImage;

    public int getFlowerId() {
        return flowerId;
    }

    public void setFlowerId(int flowerId) {
        this.flowerId = flowerId;
    }

    public String getFlowerName() {
        return flowerName;
    }

    public void setFlowerName(String flowerName) {
        this.flowerName = flowerName;
    }

    public double getFlowerPrice() {
        return flowerPrice;
    }

    public void setFlowerPrice(double flowerPrice) {
        this.flowerPrice = flowerPrice;
    }

    public String getFlowerImage() {
        return flowerImage;
    }

    public void setFlowerImage(String flowerImage) {
        this.flowerImage = flowerImage;
    }
}

package com.example.model;

import java.util.Date;

public class Order {
    private int orderId;
    private int userId;
    private int flowerId;
    private Date orderTime;
    private int orderStatus;

    public int getOrderId() {
        return orderId;
    }

    public void setOrderId(int orderId) {
        this.orderId = orderId;
    }

    public int getUserId() {
        return userId;
    }

    public void setUserId(int userId) {
        this.userId = userId;
    }

    public int getFlowerId() {
        return flowerId;
    }

    public void setFlowerId(int flowerId) {
        this.flowerId = flowerId;
    }

    public Date getOrderTime() {
        return orderTime;
    }

    public void setOrderTime(Date orderTime) {
        this.orderTime = orderTime;
    }

    public int getOrderStatus() {
        return orderStatus;
    }

    public void setOrderStatus(int orderStatus) {
        this.orderStatus = orderStatus;
    }
}

5. 编写 FlowerDao 类和 OrderDao 类，用于操作数据库：

package com.example.dao;

import com.example.model.Flower;
import com.example.utils.DBUtils;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

public class FlowerDao {
    public static List<Flower> getAllFlowers() {
        List<Flower> flowers = new ArrayList<>();

        try (Connection conn = DBUtils.getConnection();
             PreparedStatement stmt = conn.prepareStatement("SELECT * FROM flower")) {
            ResultSet rs = stmt.executeQuery();

            while (rs.next()) {
                Flower flower = new Flower();

                flower.setFlowerId(rs.getInt("flower_id"));
                flower.setFlowerName(rs.getString("flower_name"));
                flower.setFlowerPrice(rs.getDouble("flower_price"));
                flower.setFlowerImage(rs.getString("flower_image"));

                flowers.add(flower);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }

        return flowers;
    }

    public static Flower getFlowerById(int flowerId) {
        Flower flower = null;

        try (Connection conn = DBUtils.getConnection();
             PreparedStatement stmt = conn.prepareStatement("SELECT * FROM flower WHERE flower_id = ?")) {
            stmt.setInt(1, flowerId);
            ResultSet rs = stmt.executeQuery();

            if (rs.next()) {
                flower = new Flower();

                flower.setFlowerId(rs.getInt("flower_id"));
                flower.setFlowerName(rs.getString("flower_name"));
                flower.setFlowerPrice(rs.getDouble("flower_price"));
                flower.setFlowerImage(rs.getString("flower_image"));
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }

        return flower;
    }
}

package com.example.dao;

import com.example.model.Order;
import com.example.utils.DBUtils;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

public class OrderDao {
    public static List<Order> getOrdersByUserId(int userId) {
        List<Order> orders = new ArrayList<>();

        try (Connection conn = DBUtils.getConnection();
             PreparedStatement stmt = conn.prepareStatement("SELECT * FROM `order` WHERE user_id = ?")) {
            stmt.setInt(1, userId);
            ResultSet rs = stmt.executeQuery();

            while (rs.next()) {
                Order order = new Order();

                order.setOrderId(rs.getInt("order_id"));
                order.setUserId(rs.getInt("user_id"));
                order.setFlowerId(rs.getInt("flower_id"));
                order.setOrderTime(rs.getDate("order_time"));
                order.setOrderStatus(rs.getInt("order_status"));

                orders.add(order);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }

        return orders;
    }

    public static void addOrder(int userId, int flowerId) {
        try (Connection conn = DBUtils.getConnection();
             PreparedStatement stmt = conn.prepareStatement("INSERT INTO `order` (user_id, flower_id, order_time, order_status) VALUES (?, ?, ?, ?)")) {
            stmt.setInt(1, userId);
            stmt.setInt(2, flowerId);
            stmt.setObject(3, new Date());
            stmt.setInt(4, 0);
            stmt.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

6. 编写 FlowerController 类和 OrderController 类，用于处理 HTTP 请求：

package com.example.controller;

import com.example.dao.FlowerDao;
import com.example.model.Flower;

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.util.List;

@WebServlet("/flower")
public class FlowerController extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        List<Flower> flowers = FlowerDao.getAllFlowers();
        req.setAttribute("flowers", flowers);
        req.getRequestDispatcher("/WEB-INF/views/flower.jsp").forward(req, resp);
    }
}

package com.example.controller;

import com.example.dao.OrderDao;
import com.example.model.Order;

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.util.List;

@WebServlet("/order")
public class OrderController extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        int userId = (int) req.getSession().getAttribute("userId");
        List<Order> orders = OrderDao.getOrdersByUserId(userId);
        req.setAttribute("orders", orders);
        req.getRequestDispatcher("/WEB-INF/views/order.jsp").forward(req, resp);
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        int userId = (int) req.getSession().getAttribute("userId");
        int flowerId = Integer.parseInt(req.getParameter("flowerId"));
        OrderDao.addOrder(userId, flowerId);
        resp.sendRedirect(req.getContextPath() + "/order");
    }
}

7. 在 web.xml 中配置 Servlet 和 JSP：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
                             http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
         version="4.0">
    <servlet>
        <servlet-name>FlowerController</servlet-name>
        <servlet-class>com.example.controller.FlowerController</servlet-class>
    </servlet>
    <servlet>
        <servlet-name>OrderController</servlet-name>
        <servlet-class>com.example.controller.OrderController</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>FlowerController</servlet-name>
        <url-pattern>/flower</url-pattern>
    </servlet-mapping>
    <servlet-mapping>
        <servlet-name>OrderController</servlet-name>
        <url-pattern>/order</url-pattern>
    </servlet-mapping>
    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
</web-app>

8. 编写 JSP 页面，用于展示鲜花信息和订单信息：

flower.jsp：

<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>鲜花商店</title>
</head>
<body>
<h1>鲜花商店</h1>
<table>
    <thead>
    <tr>
        <th>ID</th>
        <th>名称</th>
        <th>价格</th>
        <th>图片</th>
        <th>操作</th>
    </tr>
    </thead>
    <tbody>
    <c:forEach var="flower" items="${flowers}">
        <tr>
            <td>${flower.flowerId}</td>
            <td>${flower.flowerName}</td>
            <td>${flower.flowerPrice}</td>
            <td><img src="${flower.flowerImage}" alt="${flower.flowerName}" width="100"></td>
            <td>
                <form action="${pageContext.request.contextPath}/order" method="post">
                    <input type="hidden" name="flowerId" value="${flower.flowerId}">
                    <button type="submit">购买</button>
                </form>
            </td>
        </tr>
    </c:forEach>
    </tbody>
</table>
</body>
</html>

order.jsp：

<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>我的订单</title>
</head>
<body>
<h1>我的订单</h1>
<table>
    <thead>
    <tr>
        <th>ID</th>
        <th>鲜花名称</th>
        <th>鲜花价格</th>
        <th>鲜花图片</th>
        <th>下单时间</th>
        <th>状态</th>
    </tr>
    </thead>
    <tbody>