Day38

2024-06-15 1026阅读

Day38

WEB-学生管理系统

详情页面index.jsp

学生角色:修改密码,修改信息

Day38
(图片来源网络,侵删)

老师角色:修改密码,修改信息,查询所有学生

安全退出按钮

需要的数据:姓名,角色,username

将数据从LoginServlet中拿过来,方式一:存请求里,通过请求拿过来。

方式二:存session里,通过session拿过来。

推荐:存在session里,因为请求数据在返回成功后就会消失,但是目前需要将数据保存,所以用session。

if(user!=null){
                //有相关数据,登录成功
                request.getSession().setAttribute("username",user.getUsername());
                request.getSession().setAttribute("name",user.getName());
                request.getSession().setAttribute("role",role);
                response.sendRedirect("index.jsp");
}

详情页面:



    Title
    
        body {
            display: flex;
            justify-content: center;
            align-items: center;
            height: 100vh;
            margin: 0;
            font-family: Arial, sans-serif;
            background: #f0f0f0;
            text-align: center;
        }
    



    

欢迎进入学生管理系统!

修改密码 ">修改信息 ">修改信息 查询学生 安全退出 function doOutLogin(){ window.location="DoOutLoginServlet"; }
登录-记住我功能

登录成功后退出,再次点击登录直接跳转到详情页面

rememberMe:选中了返回on,没选中返回null

逻辑:当rememberMe非空时,把数据存到cookie里面,(不是session,session在服务器,cookie在浏览器),数据存储index.jsp所需要的数据,否则跳转过去数据为空。

一个数据为一个凭证,要做三个凭证。(要传三个数据)

使用工具类做凭证:

CookieUtil类,编写方法createCookie(String key,String value,int time)

注意:1.cookie是纯文本数据。2.存储中文的时候,使用URLEncoder.encode(value,“UTF-8”)方法把value转换为中文合法。

public static Cookie createCookie(String key,String value,int time){
        try {
            Cookie cookie = new Cookie(key, URLEncoder.encode(value,"UTF-8"));
            cookie.setMaxAge(time);
            return cookie;
        } catch (UnsupportedEncodingException e) {
            throw new RuntimeException(e);
        }
    }

然后利用该工具类添加cookie:

 if(user!=null){
                //有相关数据,登录成功
                //记住我功能
                if(rememberMe!=null){
                    response.addCookie(CookieUtil.createCookie("username",user.getUsername(),60*60*24));
                    response.addCookie(CookieUtil.createCookie("name",user.getName(),60*60*24));
                    response.addCookie(CookieUtil.createCookie("role",role,60*60*24));
                }

之后再login.jsp中取凭证,如果凭证相同添加数据,都相同则直接跳转index.jsp。

 
 

注意:1.cookie会自己有一个JSESSIONID,所以此刻有四个cookie。

2.需要对之前中文编码的value进行解码。

登录成功-安全退出

DoOutLoginServlet

思路:删除Session里的数据,删除cookie里的数据,跳转。

先在CookieUtil里添加删除Cookie的功能( 通过设置一个已存在的 Cookie 的过期时间为零来删除 Cookie ):

public static void removeCookie(HttpServletResponse response,String key){
        //通过设置一个已存在的 Cookie 的过期时间为零来删除 Cookie
        response.addCookie(createCookie(key,"",0));
    }

然后使用:

package com.qf.servlet;
import com.qf.utils.CookieUtil;
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 javax.servlet.http.HttpSession;
import java.io.IOException;
@WebServlet("/DoOutLoginServlet")
public class DoOutLoginServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("UTF-8");
        response.setContentType("text/html;charSet=UTF-8");
        HttpSession session = request.getSession();
        //删除session里的数据
        session.removeAttribute("username");
        session.removeAttribute("name");
        session.removeAttribute("role");
        //删除cookie里的数据
        CookieUtil.removeCookie(response,"username");
        CookieUtil.removeCookie(response,"name");
        CookieUtil.removeCookie(response,"role");
        //跳转
        response.sendRedirect("welcome.html");
    }
}
修改密码

从详情页面直接跳转到repassword.jsp,从session中获取账号和密码。

表单:

账号、原密码、新密码、提交、返回

判断角色和账号:

方案一:在action里面拼接,缺点:action里面的信息会显示出来。

方案二:隐藏域,input type=“hidden”



    Title



    
      
          
          
          账号:
原密码:
新密码:
返回 function fun01(){ window.location="index.jsp"; }

将数据传给RepasswordServlet:

获取数据,判断角色,查询对象判断是否为空,不为空则修改,修改后安全退出,为空修改失败,设置信息返回修改页面。

package com.qf.servlet;
import com.qf.pojo.Student;
import com.qf.pojo.Teacher;
import com.qf.pojo.User;
import com.qf.utils.DBUtil;
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.sql.SQLException;
@WebServlet("/RepasswordServlet")
public class RepasswordServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("UTF-8");
        response.setContentType("text/html;charset=UTF-8");
        String username = request.getParameter("username");
        String role = request.getParameter("role");
        String password = request.getParameter("password");
        String repassword = request.getParameter("repassword");
        try {
            User user = null;
            if("student".equals(role)){
                user = DBUtil.commonQueryObj(Student.class, "select * from student where username=? and password=?", username, password);
                if(user != null){
                    DBUtil.commonUpdate("update student set password=? where username=?",repassword,username);
                }
            }else if("teacher".equals(role)){
                user = DBUtil.commonQueryObj(Teacher.class,"select * from teacher where username=? and password=?", username, password);
                if(user != null){
                    DBUtil.commonUpdate("update teacher set password=? where username=?",repassword,username);
                }
            }
            if(user != null){
                request.getRequestDispatcher("DoOutLoginServlet").forward(request,response);
            }else{
                request.setAttribute("msg","修改密码失败 -- 原密码不正确");
                request.getRequestDispatcher("repassword.jsp").forward(request,response);
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        } catch (InstantiationException e) {
            throw new RuntimeException(e);
        } catch (IllegalAccessException e) {
            throw new RuntimeException(e);
        }
    }
}
修改学生信息

修改姓名,年龄,爱好

关键:已有数据从哪里来?–Servlet中利用传过来的username从数据库中获取对象,将对象放到session里面传到stuinfo页面

StuInitModifyServlet:

package com.qf.servlet;
import com.qf.pojo.Student;
import com.qf.utils.DBUtil;
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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.sql.SQLException;
@WebServlet("/StuInitModifyServlet")
public class StuInitModifyServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("UTF-8");
        response.setContentType("text/html;charSet=UTF-8");
//        String username = (String) request.getSession().getAttribute("username");
        String username = request.getParameter("username");
        try {
            //利用账户查询学生对象
            Student student = DBUtil.commonQueryObj(Student.class, "select * from student where username=?", username);
            //将对象返回给前端
            request.setAttribute("stu",student);
            request.getRequestDispatcher("stuinfo.jsp").forward(request,response);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        } catch (InstantiationException e) {
            throw new RuntimeException(e);
        } catch (IllegalAccessException e) {
            throw new RuntimeException(e);
        }
    }
}

jsp页面根据对象获取数据

stuinfo.jsp:



    Title



    

修改学生信息


姓名:
年龄:
性别: 男 女
爱好: 足球 篮球 购物
返回 function fun01(){ window.location="index.jsp"; }

修改后将数据传回(注意要用隐藏域写账号,以便传回账号)到一个Servlet中完成对数据库信息的修改

StuModifyServlet:

package com.qf.servlet;
import com.qf.pojo.Student;
import com.qf.utils.BeanUtil;
import com.qf.utils.CookieUtil;
import com.qf.utils.DBUtil;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import java.io.IOException;
import java.sql.SQLException;
import java.util.Map;
@WebServlet("/StuModifyServlet")
public class StuModifyServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("UTF-8");
        response.setContentType("text/html;charSet=UTF-8");
        Map parameterMap = request.getParameterMap();
        Student stu = new Student();
        BeanUtil.populate(stu,parameterMap);
        System.out.println(stu);
        try {
            //更新数据库数据
            DBUtil.commonUpdate("update student set name=?,age=?,sex=?,hobbies=?",stu.getName(),stu.getAge(),stu.getSex(),stu.getHobbies());
            //更新session
            HttpSession session = request.getSession();
            session.setAttribute("name",stu.getName());
            //更新cookie
            response.addCookie(CookieUtil.createCookie("name",stu.getName(),60*60*24));
            //跳转
            response.sendRedirect("index.jsp");
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }
}
修改老师信息

老师角色->index.jsp–>TeaInitModifyServlet(根据username查询老师对象,并添加到请求中,查询所有学科对象(集合),并添加到请求中)–>teaInfo.jsp(获取请求中的老师对象和学科集合再适配到页面上,页面中有账号、姓名、学科,学科需要匹配当前账号的信息,判断老师和学科表中的id是否相同,默认选中。还有修改和返回两个按钮,修改到TeaModifyServlet,依据username修改name和courseId,更新session和cookie里的name数据,跳转到index.jsp;返回到index.jsp)。

TeaInitModifyServlet:

package com.qf.servlet;
import com.qf.pojo.Course;
import com.qf.pojo.Teacher;
import com.qf.utils.DBUtil;
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.sql.SQLException;
import java.util.List;
@WebServlet("/TeaInitModifyServlet")
public class TeaInitModifyServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("UTF-8");
        response.setContentType("text/html;charSet=UTF-8");
        String username = request.getParameter("username");
        try {
            //查询老师对象
            Teacher teacher = DBUtil.commonQueryObj(Teacher.class, "select * from teacher where username=?", username);
            // 查询所有课程对象
            List courseList = DBUtil.commonQueryList(Course.class, "select * from course");
            //返回到请求中并跳转页面
            request.setAttribute("teacher",teacher);
            request.setAttribute("courseList",courseList);
            request.getRequestDispatcher("teainfo.jsp").forward(request,response);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        } catch (InstantiationException e) {
            throw new RuntimeException(e);
        } catch (IllegalAccessException e) {
            throw new RuntimeException(e);
        }
    }
}

teainfo.jsp:





    Title


    
    

修改老师信息


姓名:
课程: 返回 function fun01(){ window.location="index.jsp"; }

TeaModifyServlet:

package com.qf.servlet;
import com.qf.pojo.Teacher;
import com.qf.utils.BeanUtil;
import com.qf.utils.CookieUtil;
import com.qf.utils.DBUtil;
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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.sql.SQLException;
import java.util.Map;
@WebServlet("/TeaModifyServlet")
public class TeaModifyServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("UTF-8");
        response.setContentType("text/html;charSet=UTF-8");
        Teacher teacher = new Teacher();
        Map parameterMap = request.getParameterMap();
        BeanUtil.populate(teacher,parameterMap);
        try {
            DBUtil.commonUpdate("update teacher set name=?,courseId=?",teacher.getName(),teacher.getCourseId());
            HttpSession session = request.getSession();
            session.setAttribute("name",teacher.getName());
            response.addCookie(CookieUtil.createCookie("name",teacher.getName(),60*60*24));
            response.sendRedirect("index.jsp");
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }
}
查询

QueryAllStuServlet

做分页假数据:

public static void main(String[] args) {
        for(int i=0;i
            String sql = "insert into student values (?,?,?,?,?,?)";
            try {
                DBUtil.commonInsert(sql,"jiashuju"+i,"123123","假数据"+i,"man",18,"football");
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
        }
    }

   @Override
   protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       this.doPost(request, response);
   }
   @Override
   protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       request.setCharacterEncoding("UTF-8");
       response.setContentType("text/html;charset=UTF-8");
       try {
           List
           throw new RuntimeException(e);
       } catch (InstantiationException e) {
           throw new RuntimeException(e);
       } catch (IllegalAccessException e) {
           throw new RuntimeException(e);
       }
   }
//      假数据
//    public static void main(String[] args) {
//        for(int i=0;i
//            String sql = "insert into student values (?,?,?,?,?,?)";
//            try {
//                DBUtil.commonInsert(sql,"jiashuju"+i,"123123","假数据"+i,"man",18,"football");
//            } catch (SQLException e) {
//                throw new RuntimeException(e);
//            }
//        }
//    }
}

    public static StudentDto studentHandler(Student student){
        String sex = student.getSex();
        if("man".equals(sex)){
            sex = "男";
        }
        if("woman".equals(sex)){
            sex = "女";
        }
        String hobbies = student.getHobbies();
        hobbies = hobbies.replaceAll("football","足球");
        hobbies = hobbies.replaceAll("basketball","篮球");
        hobbies = hobbies.replaceAll("shop","购物");
        StudentDto studentDto = new StudentDto(student,sex,hobbies);
        return studentDto;
    }
    public static List
        List
            StudentDto studentDto = studentHandler(stu);
            studentDtos.add(studentDto);
        }
        return studentDtos;
    }
}

        Connection connection = null;
        PreparedStatement statement = null;
        ResultSet resultSet = null;
        try {
            connection = getConnection();
            statement = connection.prepareStatement(sql);
            resultSet = statement.executeQuery();
            if(resultSet.next()){
                int allCount = resultSet.getInt(1);
                return allCount;
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        } finally {
            close(connection,statement,resultSet);
        }
        return 0;
    }

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("UTF-8");
        response.setContentType("text/html;charset=UTF-8");
        int curPage = Integer.parseInt(request.getParameter("curPage"));
        int count = 15;//每一页的数据条数
        int offset = (curPage-1)*count;//计算偏移量
        int allCount = DBUtil.getAllCount("select count(username) from student");//总条数
        int totalPage;//总页数
        if(allCount%count == 0){
            totalPage = allCount/count;
        }else{
            totalPage = allCount/count + 1;
        }
        try {
            String sql = "select * from student limit ?,?";
            List
            throw new RuntimeException(e);
        } catch (InstantiationException e) {
            throw new RuntimeException(e);
        } catch (IllegalAccessException e) {
            throw new RuntimeException(e);
        }
    }
}
//      假数据
//    public static void main(String[] args) {
//        for(int i=0;i
//            String sql = "insert into student values (?,?,?,?,?,?)";
//            try {
//                DBUtil.commonInsert(sql,"jiashuju"+i,"123123","假数据"+i,"man",18,"football");
//            } catch (SQLException e) {
//                throw new RuntimeException(e);
//            }
//        }
//    }
p前端中完善翻页功能/p pre class="brush:python;toolbar:false"%@ page import="com.qf.pojo.Student" % %@ page import="java.util.List" % %@ page import="com.qf.dto.StudentDto" %%-- Created by IntelliJ IDEA. User: Gu Date: 2024-06-14 Time: 20:14 To change this template use File | Settings | File Templates. --% %@ page contentType="text/html;charset=UTF-8" language="java" % html head titleTitle/title /head body % ListStudentDto stuList = (ListStudentDto) request.getAttribute("stuList"); int curPage = (int) request.getAttribute("curPage"); int totalPage = (int) request.getAttribute("totalPage"); % button οnclick="fun01()"返回/button h1学生列表页面/h1 table border="1" width="800px" tr th账号/th th姓名/th th性别/th th年龄/th th爱好/th th操作/th /tr %for(StudentDto stu:stuList){ % tr td%=stu.getStu().getUsername()%/td td%=stu.getStu().getName()%/td td%=stu.getSex()%/td td%=stu.getStu().getAge()%/td td%=stu.getHobbies()%/td td 修改 删除 /td /tr %}% /table 首页 %if(curPage1){% "上一页 %}% %if(curPagetotalPage){% ">下一页 ">尾页 function fun01(){ window.location = "index.jsp"; }
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