学生管理系统 垃圾版

实行功能

代码目录

 index页面

    
    


添加学生
查看学生

　　添加学生页面

    
    


    

        学生姓名：

        学生年龄：

        学生成绩：

        保存
    

　　添加学生Servlet

package com.itheima.servlet;

import com.itheima.bean.Student;

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.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;

/*
*
*实现添加功能
* */
@WebServlet("/addStuServlet")
public class AddStudentServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //1.获取表单中的数据
        String username=req.getParameter("username");
        String age=req.getParameter("age");
        String score = req.getParameter("score");
        //2.创建学生对象并赋值
        Student stu=new Student();
        stu.setUsername(username);
        stu.setAge(Integer.parseInt(age));
        stu.setScore(Integer.parseInt(score));

        //3.将学生对象的数据保存到d:\\stu.txt中
        BufferedWriter bw=new BufferedWriter(new FileWriter("d:\\stu.txt",true));
        bw.write(stu.getUsername()+","+stu.getAge()+","+stu.getScore());
        bw.newLine();
        bw.close();
        //通过定时刷新功能相应给浏览器
        resp.setContentType("text/html;charset=UTF-8");
        resp.getWriter().write("添加成功。2秒后自动跳转到首页");
        resp.setHeader("Refresh","2;URL=/stu/index.html");
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
}

　　学生实体类

package com.itheima.bean;

public class Student {
    private String username;
    private int age;
    private int score;

    public Student() {
    }

    public Student(String username, int age, int score) {
        this.username = username;
        this.age = age;
        this.score = score;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public int getScore() {
        return score;
    }

    public void setScore(int score) {
        this.score = score;
    }

    @Override
    public String toString() {
        return "Student{" +
                "username='" + username + '\'' +
                ", age=" + age +
                ", score=" + score +
                '}';
    }
}

　　展示学生Servlet

package com.itheima.servlet;

import com.itheima.bean.Student;

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.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;

/**
 * 实现查看功能
 * */
@WebServlet("/listStudentServlet")
public class ListStudentServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //1.创建一个字符输入流对象，关联读取的文件
        BufferedReader br=new BufferedReader(new FileReader("d:\\stu.txt"));
        //2.创建集合对象，保存Student对象
        ArrayList list=new ArrayList<>();


        //3.循环读取文件中的数据，将数据封装到Student对象中，在把多个对象添加到集合中
        String line;
        while((line= br.readLine())!=null){
            //张三,23,90
            Student stu=new Student();
            String[] split = line.split(",");
            stu.setUsername(split[0]);
            stu.setAge(Integer.parseInt(split[1]));
            stu.setScore(Integer.parseInt(split[2]));
            list.add(stu);
        }
        //4.遍历集合，将数据响应给浏览器
        resp.setContentType("text/html;charset=UTF-8");
        //获取输出流对象
        PrintWriter pw = resp.getWriter();
        for(Student s:list){
            pw.write(s.getUsername()+","+s.getAge()+","+s.getScore());
            pw.write("
");
        }

    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
}