基于javaweb的JSP+Servlet学生请假管理系统(java+servlet+mysql+jdbc+tomcat+jsp+bootstrap)

运行环境

Java≥8、MySQL≥5.7、Tomcat≥8

开发工具

eclipse/idea/myeclipse/sts等均可配置运行

适用

课程设计，大作业，毕业设计，项目练习，学习演示等

功能说明

基于javaweb的JSP+Servlet学生请假管理系统(java+servlet+mysql+jdbc+tomcat+jsp+bootstrap)

管理员：
admin 123456

学生：
a 123456
b 123456

功能：
学生可以增改查（不可以改审批状态）
老师可以删改查（可以改审批状态）

            //  随机设置当前验证码字符的颜色
            g.setColor(getRandomColor(10, 100));
            //  在图形上输出验证码字符，x和y都是随机生成的
            g.drawString(String.valueOf(codeChar), 16 * i + random.nextInt(7), height - random.nextInt(6));
        }
        HttpSession session = request.getSession();
        session.setMaxInactiveInterval(5 * 60);
        //  将验证码保存在session对象中，key为validation_code
        session.setAttribute("validationCode", validationCode.toString());
        g.dispose();//  关闭Graphics对象
        OutputStream os = response.getOutputStream();
        ImageIO.write(image, "JPEG", os);// 以JPEG格式向客户端发送图形验证码
    } else if ("resetPassword".equalsIgnoreCase(action)) {
        String msg;
        User loginUser = (User) request.getSession().getAttribute("loginUser");
        String oldPassword = request.getParameter("oldPassword");
        if (!loginUser.getPassword().equals(oldPassword)) {
            msg = "原密码错误！";
        } else {
            String newPassword = request.getParameter("newPassword");
            loginUser.setPassword(newPassword);
            UserService userService = new UserServiceImpl();
            userService.update(loginUser);
            msg = "修改成功！";
        }
        request.getSession().setAttribute("alert_msg", msg);
        request.getRequestDispatcher("reset_password.jsp").forward(request, response);
    } else {
        response.sendRedirect("login.jsp");
    }
}

/**
 * 处理Get请求
 *
 * @param request
 * @param response
 * @throws ServletException
 * @throws IOException
 */
@Override
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    doPost(request, response);
}

// 返回一个随机颜色（Color对象）
private Color getRandomColor(int minColor, int maxColor) {
    Random random = new Random();
    // 保存minColor最大不会超过255
    if (minColor > 255)
        minColor = 255;

}

/**
 * 处理Get请求
 *
 * @param request
 * @param response
 * @throws ServletException
 * @throws IOException
 */
@Override
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    doPost(request, response);//Get请求和Post请求的处理是一样的，所以把request、response转交给Post方法就好
}

/**
 * 根据参数，查询出条例条件的记录集合，最后将数据返回给调用处或者将数据集合设置到session域里，再跳转到对应的列表页面
 *
 * @param request
 * @param response
 */
private void redirectList(HttpServletRequest request, HttpServletResponse response) throws IOException {
    //查询列和关键字
    String searchColumn = request.getParameter("searchColumn");
    String keyword = request.getParameter("keyword");
    Map<String, Object> params = new HashMap();//用来保存控制层传进来的参数(查询条件)
    params.put("searchColumn", searchColumn);//要查询的列
    params.put("keyword", keyword/*keyword != null ? new String(keyword.getBytes("ISO-8859-1"), "UTF-8") : null*/);//查询的关键字
    User loginUser = (User) request.getSession().getAttribute("loginUser");
    if (!"管理员".equals(loginUser.getUserType())) {
        params.put("createBy", loginUser.getId());
    }
    LeaveService leaveService = new LeaveServiceImpl();
    Map<String, Object> map = leaveService.list(params);
    request.getSession().setAttribute("list", map.get("list"));

    Integer totalRecord = (Integer) map.get("totalCount");//根据查询条件取出对应的总记录数，用于分页
    String pageNum = request.getParameter("pageNum");//封装分页参数
    com.demo.util.PageBean<Object> pb = new com.demo.util.PageBean(Integer.valueOf(pageNum != null ? pageNum : "1"), totalRecord);
    params.put("startIndex", pb.getStartIndex());
    params.put("pageSize", pb.getPageSize());
    List list = (List) leaveService.list(params).get("list");//根据分页参数startIndex、pageSize查询出来的最终结果list
    pb.setServlet("LeaveServlet");

     * 根据参数，查询出条例条件的记录集合，最后将数据返回给调用处或者将数据集合设置到session域里，再跳转到对应的列表页面
     *
     * @param request
     * @param response
     */
    private void redirectList(HttpServletRequest request, HttpServletResponse response) throws IOException {
        //查询列和关键字
        String searchColumn = request.getParameter("searchColumn");
        String keyword = request.getParameter("keyword");
        Map<String, Object> params = new HashMap();//用来保存控制层传进来的参数(查询条件)
        params.put("searchColumn", searchColumn);//要查询的列
        params.put("keyword", keyword/*keyword != null ? new String(keyword.getBytes("ISO-8859-1"), "UTF-8") : null*/);//查询的关键字
        User loginUser = (User) request.getSession().getAttribute("loginUser");
        if (!"管理员".equals(loginUser.getUserType())) {
            params.put("createBy", loginUser.getId());
        }
        LeaveService leaveService = new LeaveServiceImpl();
        Map<String, Object> map = leaveService.list(params);
        request.getSession().setAttribute("list", map.get("list"));

        Integer totalRecord = (Integer) map.get("totalCount");//根据查询条件取出对应的总记录数，用于分页
        String pageNum = request.getParameter("pageNum");//封装分页参数
        com.demo.util.PageBean<Object> pb = new com.demo.util.PageBean(Integer.valueOf(pageNum != null ? pageNum : "1"), totalRecord);
        params.put("startIndex", pb.getStartIndex());
        params.put("pageSize", pb.getPageSize());
        List list = (List) leaveService.list(params).get("list");//根据分页参数startIndex、pageSize查询出来的最终结果list
        pb.setServlet("LeaveServlet");
        pb.setSearchColumn(searchColumn);
        pb.setKeyword(keyword);
        pb.setList(list);
        request.getSession().setAttribute("pageBean", pb);
        request.getSession().setAttribute("list", pb.getList());

        response.sendRedirect("leave_list.jsp");
    }
}

     */
    private void redirectList(HttpServletRequest request, HttpServletResponse response) throws IOException {
        //查询列和关键字
        String searchColumn = request.getParameter("searchColumn");
        String keyword = request.getParameter("keyword");
        Map<String, Object> params = new HashMap();//用来保存控制层传进来的参数(查询条件)
        params.put("searchColumn", searchColumn);//要查询的列
        params.put("keyword", keyword/*keyword != null ? new String(keyword.getBytes("ISO-8859-1"), "UTF-8") : null*/);//查询的关键字
        User loginUser = (User) request.getSession().getAttribute("loginUser");
        if (!"管理员".equals(loginUser.getUserType())) {
            params.put("id", loginUser.getId());
        }
        UserService userService = new UserServiceImpl();
        Map<String, Object> map = userService.list(params);
        request.getSession().setAttribute("list", map.get("list"));

        Integer totalRecord = (Integer) map.get("totalCount");//根据查询条件取出对应的总记录数，用于分页
        String pageNum = request.getParameter("pageNum");//封装分页参数
        com.demo.util.PageBean<Object> pb = new com.demo.util.PageBean(Integer.valueOf(pageNum != null ? pageNum : "1"), totalRecord);
        params.put("startIndex", pb.getStartIndex());
        params.put("pageSize", pb.getPageSize());
        List list = (List) userService.list(params).get("list");//根据分页参数startIndex、pageSize查询出来的最终结果list
        pb.setServlet("UserServlet");
        pb.setSearchColumn(searchColumn);
        pb.setKeyword(keyword);
        pb.setList(list);
        request.getSession().setAttribute("pageBean", pb);
        request.getSession().setAttribute("list", pb.getList());

        response.sendRedirect("user_list.jsp");
    }
}


/**
 * 这是过滤器
 * 主要负责过滤编码为utf-8及登录拦截，禁止未登录就访问
 */
public class LoginFilter implements Filter {

    //@Override
    public void destroy() {

/**
 * 用户模块的Servlet控制层，负责接收页面传过来的请求参数，根据action参数的值来确定页面要执行的具体操作<br>
 * 而后再调用UserService业务层的方法来处理具体的业务，最后将处理完成的结果返回或跳转至相应页面
 */
//@WebServlet("/UserServlet")
public class UserServlet extends HttpServlet {

    /**
     * 处理Post请求
     *
     * @param request
     * @param response
     * @throws ServletException
     * @throws IOException
     */
    @Override
    public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //过滤编码
        request.setCharacterEncoding("UTF-8");
        response.setCharacterEncoding("UTF-8");
        String action = request.getParameter("action");
        if ("add".equals(action)) {//增加
            User vo = new User();
            //取出页面传进来的各个数据，并设置到User对象的属性里
            vo.setUsername(request.getParameter("username"));
            vo.setPassword(request.getParameter("password"));
            vo.setRealName(request.getParameter("realName"));
            vo.setUserType(request.getParameter("userType"));
            vo.setCreateBy(((com.demo.vo.User) request.getSession().getAttribute("loginUser")).getId());
            UserService userService = new UserServiceImpl();
            //调用Service层增加方法（add），增加记录
            userService.add(vo);
            this.redirectList(request, response);
        } else if ("delete".equals(action)) {//删除
            //取出表要删除的用户记录的主键
            long id = Long.parseLong(request.getParameter("id"));
            UserService userService = new UserServiceImpl();
            //调用Service层删除方法（delete），将对应的记录删除
            userService.delete(id);
            this.redirectList(request, response);
        } else if ("edit".equals(action)) {//修改
            //取出页面传进来的各个数据，并设置到User对象的属性里
            User vo = new User();
            vo.setId(Long.valueOf(request.getParameter("id")));
            vo.setUsername(request.getParameter("username"));
            vo.setPassword(request.getParameter("password"));
            vo.setRealName(request.getParameter("realName"));
            vo.setUserType(request.getParameter("userType"));
            vo.setCreateBy(Long.valueOf(request.getParameter("createBy")));

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项目链接：
https://javayms.github.io?id=172325201106201sw
https://javayms.pages.dev?id=172325201106201sw