javaweb入门版学生信息管理系统-增删改查+JSP+Jstl+El

news2024/11/27 22:46:01

dao


public class StudentDao {
    QueryRunner queryRunner = QueryRunnerUtils.getQueryRunner();
    //查询全部学生信息
    public List<Student> selectStudent(){
        String sql = "select * from tb_student";
        List<Student> students = null;
        try {
            students =queryRunner.query(sql, new BeanListHandler<>(Student.class));
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return students;
    }
    //根据学生姓名查询信息
    public List<Student> selectName(String username){
        String sql = "select * from tb_student where sname = ? ";
        List<Student> list = null;
        try {
            list = queryRunner.query(sql, new BeanListHandler<>(Student.class), username);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return list;
    }
    //添加一条学生信息
    public int insert(String username,int age,String sex,String email){
        int rows = 0;
        String sql = "insert into tb_student(sname,sage,ssex,semail) values(?,?,?,?)";
        try {
            rows = queryRunner.update(sql, username, age, sex, email);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return rows;
    }
    //删除一条学生信息
    public int delete(int id){
        String sql = "delete from tb_student where sid = ?";
        int rows = 0;
        try {
            rows = queryRunner.update(sql, id);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return rows;
    }
    //修改学生信息
    public int update(int id,String username,int age,String sex,String email){
        String sql = "update tb_student set sname=?,sage=?,ssex=?,semail=? where sid = ?";
        int rows = 0;
        try {
            rows = queryRunner.update(sql, username, age, sex, email, id);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return rows;
    }
}

<%@ page import="com.etime.entity.Student" %>
<%@ page import="java.util.List" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<html>
<head>
    <title>学生信息</title>
</head>
<body>
<div align="center">
    <h1>学生信息</h1>
    <%--添加学生--%>
    <a href="insertStudent.jsp"><button>新增</button></a>
    <%--显示全部学生信息--%>
    <a href="StudentServlet?type=student"><button>查看全部</button></a>
    <%--搜索学生信息--%>
    <form action="StudentServlet" method="get">
        <input type="hidden" name="type" value="selectName">
        <input type="text"  name="selectText" placeholder="请输入要查询的人的姓名"><input type="submit" value="搜索">
    </form>
    <%--展示学生信息--%>
    <table border="2" cellpadding="0" cellspacing="0" align="center">
        <tr></tr>
        <tr>
            <th>学号</th>
            <th>姓名</th>
            <th>年龄</th>
            <th>性别</th>
            <th>邮箱</th>
            <th>操作</th>
        </tr>
        <%-- 优化版--%>
        <c:forEach var="stu" items="${list}">
            <tr>
                <td>${stu.sid}</td>
                <td>${stu.sname}</td>
                <td>${stu.sage}</td>
                <td>${stu.ssex}</td>
                <td>${stu.semail}</td>
                <td>
                    <a href="updateStudent.jsp?id=${stu.sid}&name=${stu.sname}&age=${stu.sage}&sex=${stu.ssex}&email=${stu.semail}">
                        <input type="button" value="修改"></a>
                    <a href="StudentServlet?type=delete&id=${stu.sid}">
                        <input type="button" value="删除"></a>
                </td>
            </tr>
        </c:forEach>
    </table>
    <a href="PaginationServlet?type=first"><button>首页</button></a>
    <a href="">上一页</a>
    1/12
    <a href="">下一页</a>
    <a href="PaginationServlet?type=last">尾页</a>
</div>
</body>
</html>

servlet

package com.etime.servlet;

import com.etime.dao.StudentDao;
import com.etime.entity.Student;

import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.annotation.*;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;

@WebServlet(name = "StudentServlet", value = "/StudentServlet")
public class StudentServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //防止乱码
        request.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=utf-8");

        String type = request.getParameter("type");
        //获取学生数据
        StudentDao studentDao = new StudentDao();
        if ("student".equals(type)) {
            List<Student> studentList = studentDao.selectStudent();
            request.setAttribute("list", studentList);
            request.getRequestDispatcher("showStudent.jsp").forward(request, response);
            //获取字符流，将数据显示出来
            /* PrintWriter writer = response.getWriter();
            writer.print("<h1>学生信息</h1>");
            for (Student student : studentList) {
                writer.println(student + "<br>");
            }
            writer.close();*/
        } else if ("selectName".equals(type)) {
            String selectText = request.getParameter("selectText");
            List<Student> list = studentDao.selectName(selectText);
            request.setAttribute("list", list);
            request.getRequestDispatcher("showStudent.jsp").forward(request, response);
        } else if ("insertStudent".equals(type)) {
            String name = request.getParameter("name");
            int age = Integer.parseInt(request.getParameter("age"));
            String sex = request.getParameter("sex");
            String email = request.getParameter("email");
            int i = studentDao.insert(name, age, sex, email);
            if (i != 0) {
                request.setAttribute("state", "添加成功！");
                request.getRequestDispatcher("index.jsp").forward(request, response);
                //response.sendRedirect("showStudent.jsp");
            } else {
                request.setAttribute("state", "添加失败！");
                request.getRequestDispatcher("index.jsp").forward(request, response);
                //response.sendRedirect("insertStudent.jsp");
            }
        } else if ("delete".equals(type)) {
            int id = Integer.parseInt(request.getParameter("id"));
            int i = studentDao.delete(id);
            if (i != 0) {
                request.setAttribute("state", "删除成功！");
                request.getRequestDispatcher("index.jsp").forward(request, response);
            } else {
                request.setAttribute("state", "删除失败");
                request.getRequestDispatcher("index.jsp").forward(request, response);
            }
        } else if ("newUpdate".equals(type)){
            String name = request.getParameter("name");
            //int age = Integer.parseInt(request.getParameter("age"));
            String age = request.getParameter("age");
            String sex = request.getParameter("sex");
            String email = request.getParameter("email");
            int id = Integer.parseInt(request.getParameter("id"));
            int i = studentDao.update(id, name, Integer.parseInt(age), sex, email);
            if (i != 0) {
                request.setAttribute("state", "修改成功！");
                request.getRequestDispatcher("index.jsp").forward(request, response);
            } else {
                request.setAttribute("state", "修改失败！");
                request.getRequestDispatcher("index.jsp").forward(request, response);
            }
        }

    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    }
}