Java Servlet :: How Is Session Maintained In Application Server
Aug 3, 2012
How is session maintained in the application server, internally what happens when the user has logged in ? We create a session and store the user details which will be stored in the session object in the server with a unique sessionID which will be validated when the same user login the system again? But how exactly the session is maintained in the Server internally?
I have an application developed in Jsf, hibernate eh-cache. i deployed it on jboss server and users are directly accessing jboss url on port 8080 in internal network. Now problem is, number of users for this application has been increased. This application have one page containing 20 records which gets fetched from cache on jsf page. I have used a4j:poller tag which refreshes this page via ajax call and updates it. Earlier this was working fine but nowadays number of users have been increased. Issue is i get nullpointer exception after some time once i logged in to application and user gets redirected to login page. If user re-logins he gets directed to same page number before logout. There is no reason of throwing null pointer exception and this application works fine in qualification environment. We checked everything,
1) session is still there on server. thing is user gets disconnected from it. 2) Network bandwidth seems to be okay. 3) we have used hibernate eh cache and serialized java classes.
how to troubleshoot and find root cause for this. Some people say that it is due to ajax calls from multiple users and ajax response it getting lost in between.
Coding a web application using Java 6. Try to implement the session timeout for users.
In the web.xml, I added:
<session-config> <session-timeout>480</session-timeout> <!-- jsp will expire in 8 hours --> </session-config>
Now, during the runtime, if a user does not touch the jsp page for 8 hours (after the user has signed in), the session timeout mechanism will kick in. At that point, the server side will automatically execute:
rd = req.getRequestDispatcher("/signin.jsp");
So that the user will have to re-sign in, before continue the work.
The information is getting stored in the session and i am able to retrieve the same for single user. The trouble starts when 2 user logged in from different browser (for example chrome, IE) from the same machine. The 2nd logged in user, overwrite the session information of first user.
How to prevent this.
My environment: Windows 7 64 bit, IBM websphere server, Oracle 11g, JSP, Sevrlet.
I'm making a website with articles (like a blog). I have a webpage called admin.html where you insert the data of the article (title, post etc).
Admin.html calls to a servlet and this sends the information to a SQL Database and it stores and my index.jsp calls to database and show the articles.
This works perfect, and a non-programmer can insert new articles. The problem is that I need to create an .html file for every article/post and save it into my server online.
For example if I create "CoolArticle", I need the file "CoolArticle.html" and save it in my hosting.
How I can do it? I never have seen examples online, all were local, so I can't continue.
The users of our a enterprise Java based web application must access a third web application through simple HTML links and then navigate in the target application. But for security reasons and constraints the direct exchange between the browers of users and server of the other web application is not allowed. Our web application must retrieve the web page from the other application and must return it to the users's browser. Is there a convenient way to implement this requirement in J2EE ? In this case our web application must play the role of a simple reverse proxy, must request a target JSP page from other application and process it to rewrite the URLs contained in the HTML page, then send the response to user's web browser.
I am very much new to jsp and servlet. I want to set global error page for every exception occured at server side. I am trying with following code , but something is going wrong and I am not able to c error page.
I need to implement Oauth2 with facebook to get authencation. I tried to write a servlet with the method Service, and i got the code thah i have to use in a second request.
Now i need to send a request at this URL :
1) [URL] .....
and wait for a responce with an URL that have the access_token to use with facebook
2) [URL] ....
Is it Possible in a single Servlet after i receive the "code" to send a second request to the URL in 1 and get the response with URL in 2 to retrieve the access_token?? if yes....how??
I have been developing the web applications using struts (J2ee Technology) and i have developed few web applications and send to the production. now i want to add auto update capability of the application, means if any changes was made jsp/action class then application must have capability of updating the new code.
I am trying to deploy an android application that connects to a java server. I am doing an apointments system, so the client asks for an apointments with a specific office/doctor. What i did, was to create a java server, using object for the offices, and via sockets it communicates with the android client.
The problem is that when i tried to use my (very demo still) app on my phone and sent it to some friends for testing, i coulnt find a way to have my server on the internet.
So I changed to (or trying to) servlet. But, how to do a client server application with servlets. All tutorials i have seen are more on website clients, but thats not what i need.
At our company we run a third-party Java-based GUI application on one of our Linux server machine, displaying the application to our local Windows work stations using the Cygwin X Server.We noticed a few problems with a new version of this application and was able to narrow it down to the following conditions:
1. Java Swing application running on a UNIX host; 2. Java used is 1.6 (problem not noticed when using Java 1.5) 3. Displaying to Cygwin X server (I've heard other windows-based X servers have the same issue, but I don't have access to any others at this time).
If we run the application natively on Windows, I'm told if the application runs on the Linux host and displays natively to that machine's display there are no problems (although I'm not able to verify this myself).The problems are:
1. Any new frame/dialog is opened in the geographic center of the dual displays, rather than in the middle of one or the other; 2. Any attempt to drag the window to a different location on the display seems to work, but as soon as you let go of the drag, the window snaps back to the original location. This only happens the first time you try to move each window. 3. Drop-down controls (JComboBox, for example) just close back up as soon as you click on them. If you click and drag the mouse to attempt to make a selection, no selection can be made.
Are these known problems using 1.6 on UNIX displaying to Windows-based X Servers?
The only real problem is number 3. I expect that if I put more work into the window placement, I should be able to get past number 1. Number 2 is just a minor annoyance.The following is a simple Java Swing application which when run in the correct environment will exhibit the problems.
How to force browser to open/save/save as the file from server instead of browser cache.
I am creating a csv file through a pl/sql procedure and forwarding the link to user once user clicks on link he downloads the file, however if the same thing is repeated then browser returns the old cached file instead of new file generated on server.
In stateful session bean client servlet we are explicitly setting shoppingCart to session attribute. I do not remember doing similar step withStatelessSession bean.
I am new to work on JNLP program. I have created a SWING program, JNLP file when i deploy the ear file i am getting 404 error. Please find the steps in details.
1.Created a dynamic web project JWStartProject in eclipse
2.Create a HelloWorld.java class under default package.
import javax.swing.*; public class HelloWorld extends JFrame { private static final long serialVersionUID = 4968624166243565348L; private JLabel label = new JLabel("Hello Java Web START!"); public HelloWorld() { super("Jave Web Start Example"); this.setSize(350, 200); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE ); this.setLayout(null);
[Code] ....
Now I exported this project as JWStartProject.war contains following code.
Created Server in Websphere Admin console
Deployed this war file under the server and started.
I have added MIME types also.
I am unable to launch the application. I am getting 404 errors. May I know where I went wrong?
I am currently trying to access an EJB Session deployed in a Weblogic server from JBOSS.
The client code looks like this :
Hashtable environment = new Hashtable(); environment.put(Context.INITIAL_CONTEXT_FACTORY, "weblogic.jndi.WLInitialContextFactory"); environment.put(Context.URL_PKG_PREFIXES, "weblogic.jndi.factories"); environment.put(Context.PROVIDER_URL, "t3://<ip>:<port>"); InitialContext context = new InitialContext(environment); ServiceHome home = (ServiceHome)context.lookup("ejb/Service");
When I run this code from a standalone java program it executes ok, but when I try to run it from an application deployed in JBOSS, the line (5) which creates the InitialContext object throws this Exception :
In order to be able to use weblogic naming factory I put the archive weblogic-8.1.6.0.jar in jboss's /server/default/lib directory. But I think it has to do with JNDI conflicts between JBOSS and weblogic.
When i create an application Bean how i can update it from another bean? Lets say application Bean has variable h=1 and i want to update from another bean and make it 2 how i can do it? And how i can access the value of a session bean from another bean?
The application works fine but currently there is data getting replicated among different users. Is it the problem of session data getting merged with other session data or is it server cache not getting cleared or is there any setting to be changed in weblogic application server??
When does HTTP Session object is created in web application. Suppose I have a website. Home page of website is HTTP page which contains details of company and link to Login page.
Consider below mentioned user journey as scenario:
a. user arrives at home page of website b. user click on Login page c. user fill in login details on login page and click on Submit d. user is successfully authenticated and authorized from back end e. User specific page is shown f. user click on logout link g. user is successfully logged out from website h. user is redirected to home page i. user closes browser
In the above mentioned user journey,
a. at which step does HTTP session starts (means at which steps does HTTP Session object is created ? ) b. at which step does HTTP session ends ?
In case required, assume tech stack to be Java 7, Servlet 2.5, JSP, Tomcat 7, Apache web server (for static web contents).....
Is there anything in the HTML specification about whether submitted GET or POST parameters must retain their order? E.g. In the following is there anything in the spec that says the following data should be returned in the order they appear in the HTML code. And, most importantly, is there anything that says the firstName and surname fields should actually match up with each other, i.e. the order can change but in the same way for each field?
a new java executable file which does heavy processing (batch). Development hasn't really started yet and the design phase is just beginning. Now the client is asking us to give them the minimum server specs to be able to run our application..I'm thinking this can't be done without performance testing, which will be after development. Is there a better and faster way to be able to assess this?