GP CompTech Blog: Creating a Simple Login Form using JSPs and Servlets in Eclipse

Hi Guys,

Lets try to create two jsp pages now, one is "LoginSuccess.jsp" which we redirect to, when the given input credentials are valid and other one is "LoginFailure.jsp" which we redirect to, when the given input credentials are not valid.

Step 1: Creating LoginSuccess.jsp

Right click on "WebContent" folder in "Project Explorer" of eclipse and select "New --> JSP File". "New JSP File" window will be opened. Give "LoginSuccess.jsp" as the "File name" and click "Next --> Finish". "LoginSuccess.jsp" file will be created and opened in the eclipse editor and ready for changes now.

What we do here is, we print some welcome message on this page as we know this page is getting shown to the user only when user enters correct username and password (correct in the sense, this data already persisted in the database), So we will print a welcome message of the below form,

Login Success.

Welcome <firstName> <lastName>

But, how do we get these first name and last name of the user from the "LoginSuccess.jsp" though they exist in the database. That is what the purpose of HttpSession in the LoginServlet class. If you look at the source code of "LoginServlet.java", you can observe the below lines

HttpSession session = request.getSession(true);
session.setAttribute("FirstName", rs.getString("firstname"));
session.setAttribute("LastName", rs.getString("lastname"));

Here with the first statement, we are trying to get the session from the HttpServletRequest and if session is not existed then we create a new session. In this case, session is no where existed and thus new session will be created. Then with the second and third statements, we try to add the firstname and lastname fields from the database results into the crated session with the parameters "FirstName" and "LastName". So these values will be available to any servlet through out the application.

Copy the below content into "LoginSuccess.jsp"

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Login Success</title>
</head>
<body>
 <center> 
  <center>Login Success</center>
  Welcome <%= session.getAttribute("FirstName") + " " + session.getAttribute("LastName") %> 
 </center>
</body>
</html>

Now, "LoginSuccess.jsp" will be looking like below

Step 2: Creating LoginFailure.jsp

Right click on "WebContent" folder in "Project Explorer" of eclipse and select "New --> JSP File". "New JSP File" window will be opened. Give "LoginFailure.jsp" as the "File name" and click "Next --> Finish". "LoginFailure.jsp" file will be created and opened in the eclipse editor and ready for changes now. In this page, we are going to print some error page of the below form:

Login Failed

Incorrect User ID / Password. Please try again!
Back button

Copy the below code into "LoginFailure.jsp"

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Login Failure</title>
</head>
<body>
 <center> 
  <center>Login Failed</center> 
  Incorrect User ID / Password. Please try again! <br>
  <center><input type=button name=back value=Back onClick="history.go(-1);" /></center>
 </center>
</body>
</html>

Now, "LoginFailure.jsp" will be looking like below

Step 3: Run the Login application

Right click on "LoginForm.jsp" and select "Run As --> Run on Server". "Run On Server" window will be opened. Click on "Next --> Finish". Opt for "Restart server", if it asks. Login form page will be opened now.

First let us test with some invalid input data. Enter "ganesh" in "UserId" field and "techblog" in "Password" field and click "Submit". Since this data is not existed in the database, error page (LoginFailure.jsp) will be displayed with the error message. Now, you can see the error page like below:

If you click on "Back" button then you will be coming back to previous page that is login page. So click on "Back" button.

Lets try now with the valid data. Enter "akshay" in "UserId" field and "virat123" in "Password" field and click "Submit". Since this data is already existed in the database, welcome page (LoginSuccess.jsp) will be displayed with the welcome message. Now, you can see the welcome page like below:

That is all about "Creating a Simple Login Form using JSPs and Servlets in Eclipse".

26 comments:

UnknownOctober 16, 2013 at 4:25 PM
Thank U so much for your article :-)
Explained in very easy and eye friendly manner :-)
yetanothertestingblogOctober 17, 2013 at 5:18 PM
This saved my day! I wanted also to know if there is a way where if i log in as admin, to display e.g. "Welcome to the admin panel." or if i log in as a user to display a "Welcome to the homepage, user" jsp. Basically to have multiple type of users to display different content when logged in.
Thanks a lot for this nicely explained tutorial.
Rajeshwar KalakuntlaNovember 12, 2013 at 12:13 PM
Nice and detailed explanation, nice work and keep writing..!
Thanks
UnknownNovember 27, 2013 at 5:41 PM
Thank you Very Much
UnknownNovember 27, 2013 at 5:41 PM
Thank you very much
QayyimDecember 17, 2013 at 2:07 PM
thank you sir..
you really help me this time..
i'm really grateful for this...
VijayKanthDecember 27, 2013 at 11:19 AM
Good Site explained simple and super...
UnknownDecember 27, 2013 at 11:20 AM
Thankyou very much
AnonymousMarch 6, 2014 at 8:01 AM
Brilliant article!! very helpful thank you!!
UnknownMarch 6, 2014 at 1:27 PM
Awesome its very easy to understand i like to say thank u....
UnknownMarch 6, 2014 at 1:28 PM
Awesome its very easy to understand i like to say thank u so much...
tabishMarch 7, 2014 at 3:20 PM
will this code work on Netbeans with amache server
AnonymousMarch 18, 2014 at 8:07 AM
The best article I show..Which is Very useful..and Given all step by step...Help me ...very much
AnonymousApril 3, 2014 at 10:12 PM
My family always say that I am killing my time here at web, however I know I am getting know-how every day by reading such nice posts.
ArjunMay 17, 2014 at 4:47 PM
Before watching this article i was always afraid of java but now your article have given me strength to overcome from this fear, feeling so confident right now, all scare has gone.
Thanx a ton
AnonymousOctober 3, 2014 at 2:10 PM
Thanks a lot for this !!
robinOctober 8, 2014 at 3:46 PM
thanks for your help, it is explained very simply :)
AnonymousJanuary 24, 2015 at 5:18 PM
I am getting a black screen after clicking on submit. what should be the error ? Any idea ? I just wrote the same code.
AnonymousFebruary 11, 2015 at 6:19 PM
Excellent article.. Thank you so much. This saved my time.
AnonymousFebruary 25, 2015 at 4:16 PM
After searching for ages and trying lots of other approaches, finally one where everything and all the code actually works! Not only that, but clear explanations of why the code was there or needed to be changed. Thanks so much!
AnonymousJuly 7, 2015 at 7:11 PM
very helpful.
UnknownAugust 26, 2015 at 2:38 PM
I want tabel name
AnonymousSeptember 15, 2015 at 12:41 PM
super..very helpful..

thank you so much
UnknownOctober 9, 2016 at 2:58 AM
Awesome tutorials, you just made me love Java again :)
AnonymousMarch 6, 2017 at 2:33 PM
hi!thanks for your help,it really means a lot for someone like me with interest on java..i want to develop a restaurant management system which is integrated with point of sale...what can you advice me?..where do i start?

GP CompTech Blog

Wednesday, September 25, 2013

Creating a Simple Login Form using JSPs and Servlets in Eclipse - Part 4

26 comments: