jsp手机号抽奖

import java.util.Random;

public class Lottery {
    public static String drawWinner(List<String> participants) {
        Random random = new Random();
        int index = random.nextInt(participants.size());
        return participants.get(index);
    }
}

String url = "jdbc:mysql://localhost:3306/lotterydb";
String user = "root";
String password = "password";

try (Connection conn = DriverManager.getConnection(url, user, password)) {
    // 数据库操作
} catch (SQLException e) {
    e.printStackTrace();
}

try (Connection conn = DriverManager.getConnection(url, user, password)) {
    conn.setAutoCommit(false);
    // 执行抽奖逻辑
    conn.commit();
} catch (SQLException e) {
    conn.rollback();
    e.printStackTrace();
}

<form action="draw" method="post">
    <input type="text" name="phone" placeholder="请输入手机号">
    <input type="submit" value="抽奖">
</form>

<%@ page import="java.util.List" %>
<%@ page import="java.util.ArrayList" %>
<%@ page import="java.util.Random" %>

<%
    List<String> participants = (List<String>) application.getAttribute("participants");
    if (participants == null) {
        participants = new ArrayList<>();
        application.setAttribute("participants", participants);
    }

    String phone = request.getParameter("phone");
    if (phone != null && !phone.isEmpty()) {
        participants.add(phone);
    }

    String winner = null;
    if (!participants.isEmpty()) {
        Random random = new Random();
        int index = random.nextInt(participants.size());
        winner = participants.get(index);
    }
%>
<p>中奖手机号：<%= winner != null ? winner : "暂无中奖者" %></p>