[an error occurred while processing this directive]

Login Authentication using Bean and Servlet In JSP

                         

In this section, we have developed a web application of login authentication using Bean  in JSP. Five files are used  "login.jsp", "loginbean.jsp", "welcome.jsp","LoginBean.java" and "login.java" in the code given below.

Brief description of the flow of application :

1). Create a webpage "login.jsp"  to login the user. 

2). Create a webpage "loginbean.jsp" to set the parameter using JSP Bean and forward to the Servlet page.

3). Create a bean file "LoginBean.java" to mapping the parameter from "loginbean.jsp".

4). Create a Servlet  "login.java" to validate the username and password from the database.

5). Create a webpage "welcome.jsp" display a message after successfully user login.  

 

Step:1 Create a web page  "login.jsp"  to login the user.

 

 

<html>
<head>
</head>
<body>
<form name="loginform" method="post" action="loginbean.jsp">
<br><br>
<table align="center"><tr><td><h2>Login Authentication</h2></td></tr></table>
<table width="300px" align="center" style="border:1px solid #000000;background-color:#efefef;">
<tr><td colspan=2></td></tr>
<tr><td colspan=2>&nbsp;</td></tr>
  <tr>
    <td><b>Login Name</b></td>
    <td><input type="text" name="userName" value=""></td>
  </tr>
  <tr>
    <td><b>Password</b></td>
    <td><input type="password" name="password" value=""></td>
  </tr>
  
  <tr>
    <td></td>
    <td><input type="submit" name="Submit" value="Submit"></td>
  </tr>
  <tr><td colspan=2>&nbsp;</td></tr>
</table>
</form>
</body>
</html>


 Step:2 To create a "loginbean.jsp" to set the parameter of the login.

<%page language="Java" import="java.sql.*" %>  
<HTML>   
<HEAD><TITLE>DataBase Search</TITLE></HEAD>  
<BODY>
<jsp:useBean id="db" scope="request" class="logbean.LoginBean" >
  <jsp:setProperty name="db" property="userName" value="<%=request.getParameter("userName")%>"/>
  <jsp:setProperty name="db" property="password" value="<%=request.getParameter("password")%>"/>
 </jsp:useBean>
<jsp:forward page="hello">
  <jsp:param name="username" value="<%=db.getUserName()%>" />
  <jsp:param name="password" value="<%=db.getPassword()%>" />
</jsp:forward> 
</body>
</html>


 Step:3 To create a "LoginBean.java" to mapping the parameter of  "loginbean.jsp".

package logbean;
public class LoginBean {
         
        String userName="";
      String password="";

        public String getUserName() {
            return userName;
        }
        public void setUserName(String userName) {
            this.userName = userName;
        }
    
        public String getPassword() {
            return password;
        }
        public void setPassword(String password) {
            this.password = password;
        }
    }
    


 Step:4 To create a  Servlet "login.java"  for validate the user login.

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.sql.*;
import java.sql.*;

public class login extends HttpServlet
 
   public void doPost(HttpServletRequest request, HttpServletResponse response)
                                   throws ServletException,IOException{
      response.setContentType("text/html");
      PrintWriter out = response.getWriter();

      System.out.println("MySQL Connect Example.");
      Connection conn = null;
      String url = "jdbc:mysql://localhost:3306/";
      String dbName = "user_register";
      String driver = "com.mysql.jdbc.Driver";
      String userName = "root"
      String password = "root";

       String username="";
       String userpass="";
       String strQuery= ""
      Statement st=null;
      ResultSet rs=null;
      HttpSession session = request.getSession(true);

      try {
        Class.forName(driver).newInstance();
        conn = DriverManager.getConnection(url+dbName,userName,password);
        if(request.getParameter("username")!=null &&
 request.getParameter
("username")!="" && request.getParameter("password")!=null &&
 request.getParameter
("password")!="")
        {
          username = request.getParameter("username").toString();
        userpass = request.getParameter("password").toString();
                    strQuery="select * from userregister where 
username='"
+username+"' and  password='"+userpass+"'";
           System.out.println(strQuery);
          st = conn.createStatement();
          rs = st.executeQuery(strQuery);
          int count=0;
          while(rs.next())
          {
            
            session.setAttribute("username",rs.getString(2));
            count++;
          }

                    if(count>0)
          {
            response.sendRedirect("welcome.jsp");
          }
          else
          {
                       response.sendRedirect("login.jsp");
          }
      
          
        }
        else
        {
           response.sendRedirect("login.jsp");
        }

        System.out.println("Connected to the database");       
        
        conn.close();
        System.out.println("Disconnected from database");
      catch (Exception e) {
      e.printStackTrace();
      }
  }
}


Step :5 To create the webpage "welcome.jsp" to display the message after successful message.

<HTML>   
<HEAD><TITLE>Welcome</TITLE></HEAD>  
<BODY>
<br><br><br><br>
<table align="center" style="border:1px solid #000000;">
<%
if(session.getAttribute("username")!=null && session.getAttribute("username")!="")
{
String user = session.getAttribute("username").toString();
%>
<tr><td align="center"><h1>Welcome <b><%= user%></b></h1></td></tr>
<%
}
%>
</table>
</body>
<html>


Output:

Login Authentication form :


After Successful Login user :


Download the application

                         

[an error occurred while processing this directive]