[Beginner] Best practice Backing Bean, DataBinding

Hi everybody,
I followed an oracle course in November 'Oracle Fusion Middleware 11g: Build Applications with ADF I'
Great, now I know what are the different parts of the framework.
But now I'd like to go a bit in depth.
Here is a simple example
Login page
Backing Bean
Session Bean
Read only View Object (select from view)
Application module
We have a username and password in a table but the password is encrypted in the column, in fact this is the checksum of the password.
Here is what should be done.
Login page (username, password) --> proceed button --> get data from VO --> compare usernames --> transform password coming from the login page (MD5) --> compare it to the database password -->
setting params to session bean --> redirecting to login2 page.
Here is what I have actually
I have a tuned AM with a java class having a method doLogin(String username, String password) with a String return value.
This method is exposed to the UI via a client interface.
Here are my questions.
Where do I have to check and transform all those params. In the Read Only VO via a tuned Java class extending ViewRowImpl or in the tuned AM java class ??
And now for the session bean where do I have to instanciate it. In the Backing Bean I suppose.
Wouldn't it be better to call the client interface from the backing bean, then instanciate the session bean, with params coming from the AM, in that BackBean.
I have so many question that I don't know where to begin. :-(
Kind Regards for your help.
Stessy Delcroix

Hi Frank,
thanks for your response.
Now where do I have to implement the logic behind the login.
I explain a bit the application.
We have coordinator and partner who can connect to the website.
If a coordinator didn't change the passwords for both coordinator and partner, the partner cannot login.
And a message will be displayed on the login page.
If the username or password is not correct, another message will be displayed.
Now how to return the params of the query ??
Do I have to implement the logic at the AM level or at the VO level ??
I mean calling findViewObject in the AM, play with the result of the query, implement the logic and return the params that will have to be set in a session bean
Here is the query we have
SELECT A.PASSWORD, A.TYPE, A.PROPOSAL_ID, R.CALL_ID, R.INSTRUMENT_ID, R.ONLINE_PREPARATION, A.STATUS, I.ANNEXES_UPLOAD, C.SINGLE_PARTNER, I.REFEREE_FUNCTIONALITY, A.REFEREE_ID, I.INSTRUMENT_CODE, C.TWO_PARTB_FUNCTIONALITY, C.STAGE_TYPE, EIL.SETUP_TYPE, C.CALL_CODE, I.MANDATORY_ANNEXES " +
" FROM EPSS_CREDENTIALS_VIEW A, EPSS_REGISTRATION R, EPSS_INSTRUMENT I, EPSS_CALL C, EPSS_INSTRUMENT_LIST EIL" +
" WHERE (USERNAME = ? AND A. PROPOSAL_ID = R. PROPOSAL_ID AND R.INSTRUMENT_ID = I.INSTRUMENT_ID AND C.CALL_ID = R.CALL_ID AND I.INSTRUMENT_CODE = EIL.INSTRUMENT)
All the values except Password will be set in a session bean.
I know that question is a bit annoying, but I don't want to start implementing things in the wrong way. And having dependencies between layers.
That's strange that no best practices examples have been published yet.
Thanks a lot for your precious help.
Regards,
Stessy
Edited by: Stessy.Delcroix on Mar 10, 2011 3:51 PM

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[Beginner] Best practice Backing Bean, DataBinding

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