login using jsp

msi_333 · Sat Jan 24, 2009 1:12 am

login using jsp , the login is based on session object ,here there are three files: login(Sign-in) form, check sign-in ,and logout , You can change the check of login to your program needs .here the files i made .

1 .The Main Page . contain login form
html code

<HTML>
    <HEAD>
        <TITLE>Login using jsp</TITLE>
    </HEAD>

    <BODY>
        <H1>LOGIN FORM</H1>
        <%
        String myname =  (String)session.getAttribute("username");
       
        if(myname!=null)
            {
             out.println("Welcome  "+myname+"  , <a href=\"logout.jsp\" >Logout</a>");
            }
        else 
            {
            %>
            <form action="checkLogin.jsp">
                <table>
                    <tr>
                        <td> Username  : </td><td> <input name="username" size=15 type="text" /> </td> 
                    </tr>
                    <tr>
                        <td> Password  : </td><td> <input name="password" size=15 type="text" /> </td> 
                    </tr>
                </table>
                <input type="submit" value="login" />
            </form>
            <% 
            }
        
            
            %>
        
    </BODY>
</HTML>

2. Check Login file used to check the username and password :

java code

<%
            String username = request.getParameter("username");
            String password = request.getParameter("password");
           out.println("Checking login<br>");
            if (username == null || password == null) {

                out.print("Invalid paramters ");
            }

            // Here you put the check on the username and password
            if (username.toLowerCase().trim().equals("admin") && password.toLowerCase().trim().equals("admin")) {
                out.println("Welcome " + username + " <a href=\"index.jsp\">Back to main</a>");
                session.setAttribute("username", username);
            }
           else 
               {
                out.println("Invalid username and password");
           }




%>

3. Logout file :
java code

<%

     String username=(String)session.getAttribute("username");
    if(username!=null)
        {
           out.println(username+" loged out, <a href=\"index.jsp\">Back</a>");
            session.removeAttribute("username");
            
        }
     else 
         {
         out.println("You are already not login <a href=\"index.jsp\">Back</a>");
     }



%>

violetlaura · Wed Mar 25, 2009 5:33 am

I love this~~~~~~~
Thank you.

krrish · Tue Jan 25, 2011 2:34 pm

Hi,
In your program,there is a bug.That is if you click the logout link,it'll take you to the index page but after that if you click the back button,it'll again take you the welcome page .Please check it....

goldendraco · Thu Jun 30, 2011 1:29 pm

love it
thanks

hanamant · Tue Jul 26, 2011 7:21 am

Really good one love it.................... :gOOd:

mahes · Fri Oct 07, 2011 7:01 am

hi i want to check it from the database please any one help me

Guest · Sat Nov 05, 2011 9:50 am

krrish wrote:

Hi,
In your program,there is a bug.That is if you click the logout link,it'll take you to the index page but after that if you click the back button,it'll again take you the welcome page .Please check it....

hi every one this is the best solution to the logout problem which logs out user when logout link is clicked,it also solves the problem of url, copying and pasting the url does not open the page after logout

this example consists of a sample.html page which takes name and password as input.
Please enter name as kiran and password as kiran
it then forwards to a login.jsp and if name and password are correct it sends it to a welcome.jsp page which has some links like x.jsp,y.jsp,z.jsp and p.jsp and a logout link.
the codes are shown below and are as follows:

**sample.html**

Code:

    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
    <meta http-equiv="Pragma" content="no-cache">
    <meta http-equiv="Cache-Control" content="no-cache">
    <meta http-equiv="Expires" content="Sat, 01 Dec 2001 00:00:00 GMT">
    <title>SOLVING LOGOUT PROBLEM EFFICIENTLY USING JSP</title>
    </head>
    
    <body bgcolor="#99FF66">
    <center><h1>login</h1></center>
    <center>
    <form nme="login" method="post" action="login.jsp">
    <table>
     <tr>
      <td>name:</td>
      <td><input type="text" name="name" align="right" /></td>
     </tr>
     <tr>
      <td>password:</td>
      <td><input type="password" name="password" align="right" /></td>
      </tr>
      <tr>
       <td>
       </td>
       <td><center><input type="submit" name="submit" /></center></td>
      </tr>
     </table>
     </form>
    </center>
    </body>
    </html>
    

**login.jsp**

Code:

    
    <% 
    response.setHeader("Cache-Control","no-store"); 
    response.setHeader("Pragma","no-cache"); 
    response.setDateHeader ("Expires", 0); 
    %>
    
    Read more: http://wiki.answers.com/Q/How_do_you_clear_the_browser_cache_in_jsp#ixzz1c6g2F9jR
    <%@ page contentType="text/html; charset=iso-8859-1" language="java" import="java.sql.*" errorPage="" %>
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
    <title>Untitled Document</title>
    </head>
    
    <body>
    
    <% String fname=null,fpassword=null;
    try
    {
    session.setAttribute("name",null);
    session.setAttribute("password",null);
    fname=request.getParameter("name");
    fpassword=request.getParameter("password");
    if(fname.equals("kiran")&&fpassword.equals("kiran"))
    { 
     session.setAttribute("name",fname);
     session.setAttribute("password",fpassword);
    %>
    <jsp:forward page="welcome.jsp"/>
    <%
    }
    else
    {
     %>
     <jsp:forward page="sample.html"/>
     <%
    }
    }
    catch(Exception e)
    {
     System.out.println("errror"+e);
    }
    %>
    </body>
    </html>
    
    
    **welcome.jsp**
    
    
    <% 
    response.setHeader("Cache-Control","no-store");
    response.setHeader("Pragma","no-cache"); 
    response.setDateHeader ("Expires", 0);  
    %>
    <%@ page contentType="text/html; charset=iso-8859-1" language="java" import="java.sql.*" errorPage="" %>
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
    <title>Untitled Document</title>
    </head>
    
    
    <%
    if((session.getAttribute("name"))!=null&&(session.getAttribute("password")!=null))
    {
    %>
      <body bgcolor="#99FF66"><center>
      <p>welcome<%=session.getAttribute("name")%> </p><h1 align="right"><a href="logout.jsp">logout</a></h1>
      <p>&nbsp;</p>
      <p>&nbsp;</p>
      <p>&nbsp;</p><table width="100"><tr><td align="center"><a href="x.jsp">x</a></td><td align="center"><a href="y.jsp">y</a></td></tr>
      <tr><td align="center"><a href="z.jsp">z</a></td><td align="center"><a href="p.jsp">p</a></table>
    </center>
    </body>
    <%
    }
    else
    {
    %>
    <jsp:forward page="sample.html"/>
    <%
     }
    %>
    
    </html>

then the links x.jsp,y.jsp,z.jsp,p.jsp all look same.

**x.jsp**


<% 
response.setHeader("Cache-Control","no-store"); 
response.setHeader("Pragma","no-cache"); 
response.setDateHeader ("Expires", 0);  
%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Untitled Document</title>
</head>
<%
if((session.getAttribute("name"))!=null&&(session.getAttribute("password")!=null))
{
%>
<body bgcolor="#99FF66"><h1 align="center">x</h1>
<h1 align="right"><a href="logout.jsp">logout</a></h1>
<center>
<table width="100"><tr><td align="center"><a href="#">x</a></td><td align="center"><a href="y.jsp">y</a></td></tr>
  <tr><td align="center"><a href="z.jsp">z</a></td><td align="center"><a href="p.jsp">p</a></table>
</center>
</body>
<%
}
else
{
%>
<jsp:forward page="sample.html"/>
<%
 }
%>
</html>

**y.jsp**

<% 
response.setHeader("Cache-Control","no-store");
response.setHeader("Pragma","no-cache"); 
response.setDateHeader ("Expires", 0);  
%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Untitled Document</title>
</head>
<%
if((session.getAttribute("name"))!=null&&(session.getAttribute("password")!=null))
{
%>
<body bgcolor="#99FF66"><h1 align="center">y</h1>
<h1 align="right"><a href="logout.jsp">logout</a></h1>
<center>
<table width="100"><tr><td align="center"><a href="x.jsp">x</a></td><td align="center"><a href="#">y</a></td></tr>
  <tr><td align="center"><a href="z.jsp">z</a></td><td align="center"><a href="p.jsp">p</a></table>
</center>
</body>
<%
}
else
{
%>
<jsp:forward page="sample.html"/>
<%
 }
%>
</html>

**z.jsp**

<% 
response.setHeader("Cache-Control","no-store"); 
response.setHeader("Pragma","no-cache"); 
response.setDateHeader ("Expires", 0);  
%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Untitled Document</title>
</head>
<%
if((session.getAttribute("name"))!=null&&(session.getAttribute("password")!=null))
{
%>
<body bgcolor="#99FF66"><h1 align="center">z</h1>
<h1 align="right"><a href="logout.jsp">logout</a></h1>
<center>
<table width="100"><tr><td align="center"><a href="x.jsp">x</a></td><td align="center"><a href="y.jsp">y</a></td></tr>
  <tr><td align="center"><a href="#">z</a></td><td align="center"><a href="p.jsp">p</a></table>
</center>
</body>
<%
}
else
{
%>
<jsp:forward page="sample.html"/>
<%
 }
%>
</html>

**p.jsp**

<% 
response.setHeader("Cache-Control","no-store"); 
response.setHeader("Pragma","no-cache"); 
response.setDateHeader ("Expires", 0);  
%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Untitled Document</title>
</head>
<%
if((session.getAttribute("name"))!=null&&(session.getAttribute("password")!=null))
{
%>
<body bgcolor="#99FF66"><h1 align="center">p</h1>
<h1 align="right"><a href="logout.jsp">logout</a></h1>
<center>
<table width="100"><tr><td align="center"><a href="x.jsp">x</a></td><td align="center"><a href="y.jsp">y</a></td></tr>
  <tr><td align="center"><a href="z.jsp">z</a></td><td align="center"><a href="#">p</a></table>
</center>
</body>
<%
}
else
{
%>
<jsp:forward page="sample.html"/>
<%
 }
%>
</html>

and finally on logout the code is as follows :

**logout.jsp**

<% 
response.setHeader("Cache-Control","no-store"); 
response.setHeader("Pragma","no-cache"); 
response.setDateHeader ("Expires", 0);  
%>
<%@ page contentType="text/html; charset=iso-8859-1" language="java" import="java.sql.*" errorPage="" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Untitled Document</title>
</head>

<body>

<%
session.removeAttribute("name");
session.removeAttribute("password");
session.invalidate();
%>
<jsp:forward page="sample.html"/>
</body>
</html>

Thats it hope it solves the logout problem

for any queries contact me at jaikiran.anits@gmail.com or jaikiran_cool@yahoo.com

Habbakuk · Mon Nov 07, 2011 7:21 am

Guest wrote:

Thats it hope it solves the logout problem

for any queries contact me at jaikiran.anits@gmail.com or jaikiran_cool@yahoo.com

There is still a problem, it did not work for me.

Guest · Mon Jan 02, 2012 2:16 pm

mahes wrote:

hi i want to check it from the database please any one help me

make class for connection then
write the name of the next page in form tag
example <form action="pagename.jsp">
in the second page we import the class file which make the connection and retrieving data from the database and check the username/password
example <%@page import="Exam.Validation" %>
<jsp:useBean class="Exam.Validation" id="vl" scope="session"></jsp:useBean>
then we take the user name and password form the varriable name of textbox form fist page and pass to the validation class
example <% String s=request.getParameter("Ut"); %>
<% String p=request.getParameter("Pt"); %>
and wirte the syntax if u/p wrong to forward the page
example <% if (!vl.validation(s, p ))response.sendRedirect("index.jsp?msg= invalid user Name/password"); %>

drkelly · Sun Jan 15, 2012 7:41 am

thanks..it worked for me. Very appreciated of all your help. Great forum.