jsp签到源码

CREATE TABLE user_signin (
    id INT AUTO_INCREMENT PRIMARY KEY,
    user_id INT NOT NULL,
    signin_date DATE NOT NULL,
    UNIQUE KEY (user_id, signin_date)
);

<%@ page import="java.sql.*" %>
<%
    String userId = request.getParameter("userId");
    if (userId != null) {
        Connection conn = null;
        PreparedStatement pstmt = null;
        ResultSet rs = null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "password");
            pstmt = conn.prepareStatement("SELECT * FROM user_signin WHERE user_id = ? AND signin_date = ?");
            pstmt.setInt(1, Integer.parseInt(userId));
            pstmt.setDate(2, new java.sql.Date(System.currentTimeMillis()));
            rs = pstmt.executeQuery();
            if (!rs.next()) {
                pstmt = conn.prepareStatement("INSERT INTO user_signin (user_id, signin_date) VALUES (?, ?)");
                pstmt.setInt(1, Integer.parseInt(userId));
                pstmt.setDate(2, new java.sql.Date(System.currentTimeMillis()));
                pstmt.executeUpdate();
                out.println("签到成功！");
            } else {
                out.println("今日已签到！");
            }
        } catch (Exception e) {
            e.printStackTrace();
            out.println("签到失败：" + e.getMessage());
        } finally {
            if (rs != null) rs.close();
            if (pstmt != null) pstmt.close();
            if (conn != null) conn.close();
        }
    } else {
        out.println("用户ID不能为空！");
    }
%>