Difference between stateful and stateless session beans

can any body explain simply what is the difference between stateful and stateless session beans? also in what kind of situations we can use these.

Hi
This is the classificatio os Session Bean.
(1) Statfull
(2) Stateless
Stateful means u will persists the state of the object.
USESE:
In a Banking system u can use the statful session just for maintaing the
state.
(2) STATELESS: that's mean u do't want to persists any state of the object. that's mean a single Request is coming ,do the desire and give the output.
EX: A Credit Card System is the Example of Stateless.
May it will helpfull to understands u. if any need write here
saM

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How to get stateful and stateless session bean in second jsp

I create stateful session bean in the first jsp, then how can I get the stateful session bean in the second jsp? I find that somebody store the bean in HttpSession.
If I store the stateful session bean in HttpSession, then I can get it in the second jsp. My problem is that I can store the stateless session bean in HttpSession, and get it in the second jsp. Then, both stateful and stateless can maintain the state in the second jsp. What is the difference between stateful and stateless session bean in this case ?
I understand the definition of stateful and stateless session bean, but I'm confuse how to use session bean. Can anyone provide sample jsp to show difference of stateful and stateless? How the stateful session bean can maintain the state for the client?

Greetings,
I create stateful session bean in the first jsp, then how can I get the stateful session bean in the
second jsp? I find that somebody store the bean in HttpSession.Which is the correct scope for sharing client-specific data when 'request' scope is insufficient.
If I store the stateful session bean in HttpSession, then I can get it in the second jsp. My problem is
that I can store the stateless session bean in HttpSession, and get it in the second jsp. Then, bothWhy is that a "problem"? Does your application not require the stateless bean to be shared? If so, then don't store the EJBObject reference in the session...
stateful and stateless can maintain the state in the second jsp. What is the difference betweenWhat do you mean by this exactly?..
stateful and stateless session bean in this case ?Statefulness of session beans is in regard to maintaining client state (er, in all cases). If your "stateless" bean is receiving information from the client (i.e. its caller) - either through a create method or a business method - and that information is available (retrievable from the bean) on subsequent method calls, then that bean is, in fact, stateful - regardless of how it is deployed.
I understand the definition of stateful and stateless session bean, but I'm confuse how to use
session bean.The correct question, it here seems, is "when" to use which type... Use a "stateful" bean when information about (from) the client (i.e. the caller) must be maintained across method calls of the bean. Use a "stateless" bean for general business methods that do not depend on "prior knowledge" of the client (i.e. the caller).
Can anyone provide sample jsp to show difference of stateful and stateless? How the statefulA "sample JSP" would yield nothing additional... The semantics of calling, using, and "persisting", bean references are always the same - regardless of type or class. However, the reason(s) for using one over the other depends entirely on the needs of your application.
session bean can maintain the state for the client?I recommend that you spend more time learning about EJBs generally. In particular, it seems you require more fundamental understanding of their scope and lifecycle. Refer to sections 4, 6, and 7 of the EJB 2.0 Specification.
Regards,
Tony "Vee Schade" Cook

Stateful vs. stateless session bean

Hi,
I am following the pattern of accessing entity beans with a session bean wrapper. I am just wondering if it's more efficient to make it a stateful session bean by keeping references to the home interfaces or make it stateless and do a lookup every time the session bean is created/activated?
I suppose the number of entity beans I want to access might make a difference. If so, is there a rough number when one way becomes better than the other?
Thanks for any help in advance.
Jeff

- It is far better to use a stateless session bean when implementing the session-facade pattern.
- Keeping a home interface on the object won't make him stateful.
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/Stephane

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I am using VPD, BC4J and the Struts version included in JDEV 9.0.3 final version.
When I am calling
String userName = getUserPrincipalName();
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An Example that will cause this problem:
User 1: Goes to a web page using a stateful AM
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when user 2 goes to a stateful page he will retrieve
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My questions are:
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Ahhh forgot to add something...
if you want to keep your existing exception hirarchy (ABCException extends RemoteException).
then make sure that in your statefull session bean the order of the catch block is first the catch(ABCException) and then the remote exception.
If the catch block for remote exception comes first, then the ABCException will be sent to that block itself because ABCException is a sub class of remote exception.
However, IMHO, business exceptions should not extend the remote exception... as the RemoteException is used to report technical errors and not business errors.
hope this helps ....
regards,
Abhishek.

WLS10 and Stateless Session Bean

I tried to create EJB3 application example.
1. Created Stateless Session Bean that implements Remote and Local interfaces:
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package com.session;
import javax.ejb.Local;
import javax.ejb.Remote;
import javax.ejb.Stateless;
import javax.ejb.TransactionAttribute;
import javax.ejb.TransactionAttributeType;
@Stateless(mappedName="SessionBeanService")
@Remote(ISessionBeanRemote.class)
@Local(ISessionBeanLocal.class)
@TransactionAttribute(TransactionAttributeType.REQUIRED)
public class SessionBean implements ISessionBeanLocal,
ISessionBeanRemote
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return "MySessionBean - success !!!";
Remote Interface code :
package com.session;
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Local Interface code:
package com.session;
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application.xml:
<?xml version="1.0" encoding="UTF-8"?>
<application xmlns="http://java.sun.com/xml/ns/javaee"
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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE weblogic-application PUBLIC
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<weblogic-application>
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</weblogic-application>
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I didn't include any weblogic specific XML descriptors besides weblogic-application.jar.
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// THIS JNDI NAME I SEE ON MY SERVER JNDI TREE
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Exception occurred!
java.lang.ClassCastException: Cannot narrow remote object to com.session.ISessionBeanRemote
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     at ca.cgi.mvest.test.server.wms.GlFacadeTest.runTest(GlFacadeTest.java:91)
     at ca.cgi.mvest.test.server.wms.GlFacadeTest.<init>(GlFacadeTest.java:53)
     at ca.cgi.mvest.test.server.wms.GlFacadeTest.main(GlFacadeTest.java:151)
java.lang.ClassCastException: Cannot narrow remote object to com.session.ISessionBeanRemote
My server console have the following output:
Root cause of ServletException.java.lang.NoClassDefFoundError: com/session/SessionBean_7pp7ls_ISessionBeanRemot
eIntf
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:12
4)
at weblogic.utils.classloaders.GenericClassLoader.defineClass(GenericCla
ssLoader.java:338)
at weblogic.utils.classloaders.GenericClassLoader.findLocalClass(Generic
ClassLoader.java:291)
Truncated. see log file for complete stacktrace
Server logs a problem already on the line when I do lookup
on JNDI name even before narrow();
It looks like my EAR was missing something. But server never complained during deployment.
May be someone can direct me to a real sample of Weblogic10-ejb3.0 application, since examples that come with WLS 10 intallation combersome and do not follow
docmentation.
Thanks in advance for any suggestion.

Hello Freind
The main different b\w stateful and statless is that stateful maintain state of method conversation means it has record that which method call before this method
but in case of stateless conversation state does not saved second different we can say that create method in stateless having no parameter but statefull having parameter I think u can understand easily
With Best Regards
Rajesh Pandey
email :[email protected]
url :-- http://www.sixthquadrant.com
Mob :-- 9811903737
Delhi India

How to use jta in toplink and stateless session bean EJB 3.0?

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Yuichi
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What is the recommended procedure for making hot deployment of Stateless session beans work with toplink in WLS 7.0sp1 and oc4j (9.0.3)
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JCo 3.0 Server and Stateless Session Bean

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I use JCO (3.0) and I need to integrate SAP with JBoss.
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The program ID should be with length 8 max

Basic difference between stateful and entity beans???

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Thank u very much crackers for ur valuable
suggestions.I'll throw a different one in here for free: clarity of writing is a highly-valued and useful skill in a software professional. This is especially true these days when concepts need to be clearly explained to a variety of technical peoples from all over the world. And then there's the other side of the coin: Management.
You have to get your thoughts across in a very precise manner and, unfortunately for those who have to learn it as a second lanugage, English seems to be the overall preferred medium. Which makes it even more important to use "correct" English in written communications. If you don't, your credibility diminishes and you appear to be (horrors!) unprofessional It's not that much harder to type "you" than it is to use a single letter. Besides, most people that "pay by the byte" appreciate the clarity, as well (as I've seen on Usenet, by way of covering my ass).
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Is this wat u were trying to say if i
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Hi,
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http://help.sap.com/saphelp_nw70ehp2/helpdata/en/9f/db9df735c111d1829f0000e829fbfe/frameset.htm
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Aru,
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Hi
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or
2.- Specified directly in the bean with a weblogic annotation, like this:
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Im in the process of designing a small card game(2-4 concurrent players), and I need to keep the state stored somewhere. I was thinking about putting most of the functionality together with state in a stateful session bean, but that doesnt scale very well.
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Is this a good solution which will scale well?
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Hint:
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http://java.sun.com/j2ee/1.4/docs/tutorial-update2/doc/EJBConcepts3.html

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My best advice: surrender to use an IDE.
You wonder sometimes at how much productivity (read as 'time') could be wasted by doing something that could be done automatically. For a learning experience or a once only exercise is fine but as a routine thing, not worth it.
Cheers

Difference between stateful and stateless session beans

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