Best Practice for EJB calls from servlet?

Hi folks
I could not find general rules for making calls to an stateful EJB from the web container (e.g. from a backingBean). In some books they say it is a bad programming style calling them directly from a common servlet. The book says create first an HTTPSession Object and from there call the stateful EJB.
I'm a bit confused because, I'm missing some best practice guide from where to initiate such calls.
Can somebody please point me in the right direction?
Kind Regards
Bruno
Edited by: zajoho on Oct 30, 2008 11:14 PM

Hi Bruno,
The main issue with the combination of stateful session beans and servlets is the servlet threading model.
It is dangerous to store a stateful session bean reference in servlet instance state, since the servlet instance
can be accessed concurrently, yet a stateful session bean reference is intended to be used by only one
client.
As you point out, one alternative is to store the reference in the HttpSession. That associates the reference
with a particular client, which matches the stateful session bean programming model.

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Hello,
nice to get feedback.
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J.
Edited by: jduprez on May 9, 2011 10:10 AM

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You are right. I was referring to stateless session
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%

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Attachments:
test.vi ‏27 KB
Sequence File 2.seq ‏9 KB

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Here you go, bro!
http://checkthenetwork.com/networksecurity%20Cisco%20ASA%20Firewall%20Best%20Practices%20for%20Firewall%20Deployment%201.asp#_Toc218778855
access-list inside permit icmp any any echo
access-list inside permit icmp any any echo-reply
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Hi guys
As you may be aware, based on my other thread here. I'm designing a card game in Java. I was hoping for some advice on the best practise on how methods should be called on a custom Object contained within a custom Collection.
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Edited by: Faz_86 on Jul 10, 2010 9:53 AM

Hey Saish
Thanks for the response.
My Card class does indeed override hashCode(), equals() and toString().
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Edited by: 948115 on Jul 23, 2012 6:19 AM

948115 wrote:
Dear All,
This is Priya.
We are using ODI 11.1.1.6 version.
In my ODI project, we have separate installations for Dev, Test and Prod. i.e. Master repositories are not common between all the three. Now my code is ready in dev. Test environment is just installed with ODI and Master and Work repositories are created. Thats it
Now, I need to know and understand what is the simple & best way to import the code from Dev and migrate it to test environment. Can some one brief the same as a step by step procedure in 5-6 lines? If this is the 1st time you are moving to QA, better export/import complete work repositories. If it is not the 1st time then create scenario of specific packages and export/import them to QA. In case of scenario you need not to bother about model/datastores. keep in mind that the logical schema name should be same in QA as used in your DEV.
Some questions on current state.
1. Do the id's of master and work repositories in Dev and Test need to be the same?It should be different.
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http://docs.oracle.com/cd/E14571_01/integrate.1111/e12643/export_import.htm
http://odiexperts.com/odi-internal-id/
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>
Thanks,
Priya
Edited by: 948115 on Jul 23, 2012 6:19 AM

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Hi,
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Best Regards,
Joyce

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