Java --- Login Register of Projects and CRUD (jsp + servlet)

Login registration and CRUD (jsp + servlet)

(A) Features

1. The user enters the correct password to log in

2. New users can register

3. To display the student's login information table

4. You can add students

5. Students can modify existing information

6. You can delete the existing student

7. You can display the user logged on student number (each page can be displayed by calling the session)

8. The views may be recorded

(B) show page

log in page

 

registration page

 

Student Information Page

 

Add Page

 

Student Information table after the add

 

Modify page

 

Student Information table after revision

 

Student Information table after deletion

 

(C) the project code

 

package entity;

public class Student {
     private String sno;
     private String password;
     private String name;

    public Student(String sno, String password, String name) {
        this.sno = sno;
        this.password = password;
        this.name = name;
    }

    public String getSno() {
        return sno;
    }

    public void setSno(String sno) {
        this.sno = sno;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

 

package util;



import entity.Student;



import java.util.HashMap;



public class StudentUtil {

    public static HashMap<String, Student> map=new HashMap<String,Student>();

    static{

        map.put("101",new Student("101","123","lili"));

        map.put("102",new Student("102","123","lisa"));

        map.put("103",new Student("103","123","coco"));

        map.put("104",new Student("104","123","mark"));

    }

    public static boolean log(Student stu){

        boolean b=false;

        for(String s:map.keySet()){

            if(map.get(s).getSno().equals(stu.getSno())&&map.get(s).getPassword().equals(stu.getPassword())){

                b=true;

            }

        }

        return b;

    }

    public static boolean reg(Student stu){

        map.put(stu.getSno(),stu);

        return true;

    }

}

 

package servlet;



import entity.Student;

import org.omg.CORBA.Request;

import util.StudentUtil;



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;

@WebServlet("/LoginServlet")

public class LoginServlet extends HttpServlet {

    @Override

    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String sno=req.getParameter("sno");

        String password=req.getParameter("password");

        Student s=new Student(sno,password,null);

        boolean b=StudentUtil.log(s);

        if(b==true){

            req.setAttribute("sno",sno);

            req.getRequestDispatcher("logon.jsp").forward(req,resp);

        }else{

            req.getRequestDispatcher("error.jsp").forward(req,resp);

        }

    }



    @Override

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        doPost(req, resp);

    }

}

 

package servlet;



import entity.Student;

import util.StudentUtil;



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;

@WebServlet("/RegisterServlet")

public class RegisterServlet extends HttpServlet {

    @Override

    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String sno=req.getParameter("sno");

        String password=req.getParameter("password");

        String name=req.getParameter("name");

        StudentUtil.reg(new Student(sno,password,name));

        req.getRequestDispatcher("/index.jsp").forward(req,resp);

    }



    @Override

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        doPost(req, resp);

    }

}

 

package servlet;



import entity.Student;

import util.StudentUtil;



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;

@WebServlet("/InsertServlet")

public class InsertServlet extends HttpServlet {

    @Override

    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String sno=req.getParameter("sno");

        String password=req.getParameter("password");

        String name=req.getParameter("name");

        StudentUtil.map.put(sno,new Student(sno,password,name));

        req.getRequestDispatcher("student.jsp").forward(req,resp);

    }



    @Override

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        doPost(req, resp);

    }

}

 

package servlet;



import util.StudentUtil;



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;

@WebServlet("/UpdateServlet")

public class UpdateServlet extends HttpServlet {

    @Override

    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String sno=req.getParameter("sno");

        String password=req.getParameter("password");

        String name=req.getParameter("name");

        StudentUtil.map.get(sno).setName(name);

        StudentUtil.map.get(sno).setPassword(password);

        req.getRequestDispatcher("student.jsp").forward(req,resp);

    }



    @Override

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        doPost(req, resp);

    }

}

package servlet;



import util.StudentUtil;



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;

@WebServlet("/DeleteServlet")

public class DeleteServlet extends HttpServlet {

    @Override

    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

       String sno= req.getParameter("sno");

        StudentUtil.map.remove(sno);

        req.getRequestDispatcher("student.jsp").forward(req,resp);

    }



    @Override

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        doPost(req, resp);

    }

}

 

 

index.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<html>

<head>

    <title>Title</title>

</head>

<body>

<form action="LoginServlet" method="post">

    <div class="log">

        <h2>登录</h2>

        学号：<input type="text" name="sno"><br>

        密码：<input type="password" name="password"> <br>

        <input type="submit" value="确认登录">

        <a href="register.jsp" >注册</a>

    </div>

</form>

</body>

</html>

 

register.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<html>

<head>

    <title>Title</title>

</head>

<body>

<form action="RegisterServlet" method="post">

    学号：<input type="text" name="sno"><br>

    密码：<input type="text" name="password"><br>

    姓名：<input type="text" name="name"><br>

    <input type="submit" value="确认">

</form>

</body>

</html>

 

 

logon.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<html>

<head>

    <title>Title</title>

</head>

<body>

<%

    session.setAttribute("sno",request.getAttribute("sno"));

    Object o=application.getAttribute("count");

    if(o==null){

        application.setAttribute("count",1);

    }else{

        int c=Integer.parseInt(o.toString());

        application.setAttribute("count",c+1);

    }

%>

<%

request.getRequestDispatcher("student.jsp").forward(request,response);

%>

</body>

</html>

 

student.jsp

<%@ page import="util.StudentUtil" %>

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<html>

<head>

    <title>Title</title>

</head>

<body>



<a href="insert.jsp">增加</a>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

<span>用户：<%=session.getAttribute("sno")%></span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

<span>浏览量：<%=application.getAttribute("count")%></span>

<table>

    <tr>

        <td>学号</td>

        <td>密码</td>

        <td>姓名</td>

        <td></td>

    </tr>

    <%

      for(String s: StudentUtil.map.keySet()){%>

          <tr>

              <td><%=StudentUtil.map.get(s).getSno()%></td>

              <td><%=StudentUtil.map.get(s).getPassword()%></td>

              <td><%=StudentUtil.map.get(s).getName()%></td>

              <td><a href="update.jsp?sno=<%=StudentUtil.map.get(s).getSno()%>&&password=<%=StudentUtil.map.get(s).getPassword()%>&&name=<%=StudentUtil.map.get(s).getName()%>">修改</a>

                  <a href="DeleteServlet?sno=<%=StudentUtil.map.get(s).getSno()%>">删除</a></td>

          </tr>

     <% } %>

</table>



</body>

</html>

 

error.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<html>

<head>

    <title>Title</title>

</head>

<body>

账户名或密码错误

<a href="index.jsp">返回登录</a>

</body>

</html>

 

 

insert.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<html>

<head>

    <title>Title</title>

</head>

<body>

<form action="InsertServlet" method="post">

    学号：<input type="text" name="sno"/><br>

    密码：<input type="text" name="password"/><br>

    姓名：<input type="text" name="name"/><br>

    <input type="submit" value="确认添加">

</form>



</body>

</html>

 

 

update.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<form action="UpdateServlet" method="post">
    <table>
        <tr>
            <td>学号</td>
            <td><input type="text" name="sno" value="<%=request.getParameter("sno")%>"></td>
        </tr>
        <tr>
            <td>密码</td>
            <td><input type="text" name="password" value="<%=request.getParameter("password")%>"></td>
        </tr>
        <tr>
            <td>姓名</td>
            <td><input type="text" name="name" value="<%=request.getParameter("name")%>"></td>
        </tr>
    </table>
    <input type="submit" value="确认修改">
</form>
</body>
</html>