用SpringMVC+jdbc写一个课堂签到管理系统

好的，下面是一个简单的课堂签到管理系统的实现，使用SpringMVC框架和JDBC进行数据库操作。

首先，我们需要创建一个数据库，其中包含两个表：学生表和签到表。学生表包括学生的学号、姓名和班级；签到表包括签到记录的id、学生的学号、签到时间和签到状态（已签到或未签到）。

1. 创建数据库：

CREATE DATABASE `class_sign` CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

USE `class_sign`;

CREATE TABLE `student` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `stu_no` varchar(20) DEFAULT NULL,
  `name` varchar(20) DEFAULT NULL,
  `class` varchar(20) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

CREATE TABLE `sign` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `stu_no` varchar(20) DEFAULT NULL,
  `sign_time` datetime DEFAULT NULL,
  `status` varchar(10) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

2. 创建Maven项目，并添加SpringMVC和JDBC的依赖：

<dependencies>
    <!-- SpringMVC -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>5.3.9</version>
    </dependency>
  
    <!-- JDBC -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.26</version>
    </dependency>
</dependencies>

3. 配置web.xml文件，指定DispatcherServlet的映射和路径：

<web-app>
    <display-name>class-sign</display-name>
  
    <servlet>
        <servlet-name>dispatcherServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>/WEB-INF/classes/springmvc-config.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
  
    <servlet-mapping>
        <servlet-name>dispatcherServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

4. 配置SpringMVC的配置文件springmvc-config.xml，包括视图解析器和控制器的配置：

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd">

    <!-- 视图解析器 -->
    <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/views/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

    <!-- 控制器配置 -->
    <mvc:annotation-driven/>
    <context:component-scan base-package="com.example.controller"/>

    <!-- 数据源配置 -->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.cj.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/class_sign?useUnicode=true&amp;characterEncoding=utf-8&amp;serverTimezone=GMT%2B8"/>
        <property name="username" value="root"/>
        <property name="password" value="root"/>
    </bean>

    <!-- JDBC模板配置 -->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="dataSource"/>
    </bean>
</beans>

5. 创建学生实体类Student和签到实体类Sign：

public class Student {
    private Integer id;
    private String stuNo;
    private String name;
    private String clazz;
    // getter和setter方法
}

public class Sign {
    private Integer id;
    private String stuNo;
    private Date signTime;
    private String status;
    // getter和setter方法
}

6. 创建学生的DAO类StudentDao和签到的DAO类SignDao，并实现相应的方法：

@Repository
public class StudentDao {
    @Autowired
    private JdbcTemplate jdbcTemplate;

    public List<Student> findAll() {
        String sql = "SELECT * FROM student";
        return jdbcTemplate.query(sql, new BeanPropertyRowMapper<>(Student.class));
    }

    public Student findByStuNo(String stuNo) {
        String sql = "SELECT * FROM student WHERE stu_no = ?";
        List<Student> list = jdbcTemplate.query(sql, new BeanPropertyRowMapper<>(Student.class), stuNo);
        return list.size() == 0 ? null : list.get(0);
    }

    public int add(Student student) {
        String sql = "INSERT INTO student(stu_no, name, class) VALUES(?, ?, ?)";
        return jdbcTemplate.update(sql, student.getStuNo(), student.getName(), student.getClazz());
    }

    public int delete(Integer id) {
        String sql = "DELETE FROM student WHERE id = ?";
        return jdbcTemplate.update(sql, id);
    }
}

@Repository
public class SignDao {
    @Autowired
    private JdbcTemplate jdbcTemplate;

    public int add(Sign sign) {
        String sql = "INSERT INTO sign(stu_no, sign_time, status) VALUES(?, ?, ?)";
        return jdbcTemplate.update(sql, sign.getStuNo(), sign.getSignTime(), sign.getStatus());
    }

    public List<Sign> findByStuNo(String stuNo) {
        String sql = "SELECT * FROM sign WHERE stu_no = ?";
        return jdbcTemplate.query(sql, new BeanPropertyRowMapper<>(Sign.class), stuNo);
    }

    public int delete(Integer id) {
        String sql = "DELETE FROM sign WHERE id = ?";
        return jdbcTemplate.update(sql, id);
    }
}

7. 创建控制器类SignController，实现学生的添加和删除、签到的添加和查询功能：

@Controller
@RequestMapping("/sign")
public class SignController {
    @Autowired
    private StudentDao studentDao;

    @Autowired
    private SignDao signDao;

    @RequestMapping("/toAdd")
    public String toAdd(Model model) {
        model.addAttribute("student", new Student());
        return "add";
    }

    @RequestMapping("/add")
    public String add(Student student) {
        studentDao.add(student);
        return "redirect:/sign/list";
    }

    @RequestMapping("/delete/{id}")
    public String delete(@PathVariable("id") Integer id) {
        studentDao.delete(id);
        return "redirect:/sign/list";
    }

    @RequestMapping("/list")
    public String list(Model model) {
        List<Student> students = studentDao.findAll();
        model.addAttribute("students", students);
        return "list";
    }

    @RequestMapping("/toSign")
    public String toSign(Model model) {
        model.addAttribute("sign", new Sign());
        return "sign";
    }

    @RequestMapping("/sign")
    public String sign(Sign sign) {
        String stuNo = sign.getStuNo();
        Student student = studentDao.findByStuNo(stuNo);
        if (student == null) {
            return "error";
        }
        sign.setSignTime(new Date());
        sign.setStatus("已签到");
        signDao.add(sign);
        return "redirect:/sign/signList/" + stuNo;
    }

    @RequestMapping("/signList/{stuNo}")
    public String signList(@PathVariable("stuNo") String stuNo, Model model) {
        List<Sign> signs = signDao.findByStuNo(stuNo);
        model.addAttribute("signs", signs);
        return "signList";
    }

    @RequestMapping("/deleteSign/{id}")
    public String deleteSign(@PathVariable("id") Integer id) {
        Sign sign = signDao.findById(id);
        if (sign == null) {
            return "error";
        }
        signDao.delete(id);
        return "redirect:/sign/signList/" + sign.getStuNo();
    }
}

8. 创建视图文件，包括学生添加页面add.jsp、学生列表页面list.jsp、签到页面sign.jsp和签到列表页面signList.jsp：

add.jsp：

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>添加学生</title>
</head>
<body>
<h1>添加学生</h1>
<form action="${pageContext.request.contextPath}/sign/add" method="post">
    学号：<input type="text" name="stuNo"/><br/>
    姓名：<input type="text" name="name"/><br/>
    班级：<input type="text" name="clazz"/><br/>
    <input type="submit" value="添加"/>
</form>
<hr/>
<a href="${pageContext.request.contextPath}/sign/list">查看所有学生</a>
</body>
</html>

list.jsp：

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>学生列表</title>
</head>
<body>
<h1>学生列表</h1>
<table border="1">
    <tr>
        <th>ID</th>
        <th>学号</th>
        <th>姓名</th>
        <th>班级</th>
        <th>操作</th>
    </tr>
    <c:forEach items="${students}" var="student">
        <tr>
            <td>${student.id}</td>
            <td>${student.stuNo}</td>
            <td>${student.name}</td>
            <td>${student.clazz}</td>
            <td>
                <a href="${pageContext.request.contextPath}/sign/delete/${student.id}">删除</a>
            </td>
        </tr>
    </c:forEach>
</table>
<hr/>
<a href="${pageContext.request.contextPath}/sign/toAdd">添加学生</a>
<a href="${pageContext.request.contextPath}/sign/toSign">学生签到</a>
</body>
</html>

sign.jsp：

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>学生签到</title>
</head>
<body>
<h1>学生签到</h1>
<form action="${pageContext.request.contextPath}/sign/sign" method="post">
    学号：<input type="text" name="stuNo"/><br/>
    <input type="submit" value="签到"/>
</form>
<hr/>
<a href="${pageContext.request.contextPath}/sign/list">查看所有学生</a>
<a href="${pageContext.request.contextPath}/sign/toSign">学生签到</a>
</body>
</html>

signList.jsp：

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>签到列表</title>
</head>
<body>
<h1>签到列表</h1>
<table border="1">
    <tr>
        <th>ID</th>
        <th>学号</th>
        <th>签到时间</th>
        <th>签到状态</th>
        <th>操作</th>
    </tr>
    <c:forEach items="${signs}" var="sign">
        <tr>
            <td>${sign.id}</td>
            <td>${sign.stuNo}</td>
            <td>${sign.signTime}</td>
            <td>${sign.status}</td>
            <td>
                <a href="${pageContext.request.contextPath}/sign/deleteSign/${sign.id}">删除</a>
            </td>
        </tr>
    </c:forEach>
</table>
<hr/>
<a href="${pageContext.request.contextPath}/sign/list">查看所有学生</a>
<a href="${pageContext.request.contextPath}/sign/toSign">学生签到</a>
</body>
</html>

这样，我们就完成了一个简单的课堂签到管理系统的实现，使用了SpringMVC框架和JDBC进行数据库操作。