Rick,
Let's examine this stateless session bean. I believe this is
what Mark Hapner is referring to in his email as "another tier"
that sits between between the client (servlet) and the entity bean.
public interface Account extends javax.ejb.EJBObject {
public void setName(String name);
public void setNumber(String number);
public void setBalance(String balance);
public void setAccountValue(AccountValue value);
}
public class AccountValue {
public String name;
public String number;
public String balance;
}
public interface BankAssociate extends javax.ejb.EJBObject {
// stateless session bean wrapping Account
public void setupAccount(AccountValue value);
public void modifyAccount(AccountValue value);
}
where setupAccount will blindly call all setXXX methods
in Account's interface and modifyAccount will only call
those setXXX methods where a corresponding property in
AccountValue is not null. Both of these cases can be
handled by putting the very same logic into the implementation of
Account's setAccountValue method and therefore eliminating
the need for BankAssociate altogether. If so, all setXXX methods can be made
private and not show up in Account's interface.
Is there a better solution that I am not considering?
Alex Smith
INSight LLC
>From: Rick Kitts <[EMAIL PROTECTED]>
>Reply-To: [EMAIL PROTECTED]
>To: [EMAIL PROTECTED]
>Subject: Re: [EJB-INT] Demarcating transactions
>Date: Fri, 30 Jun 2000 08:10:51 -0700
>
>(I'm brand new to this EJB stuff so apologies if I'm completely
>off base here.)
>
>I don't understand the all or nothing sort of scheme implied
>by the commentary. Is it not reasonable to create this flow?
>
>1 - Servlet gets data and bulks them up
>2 - Servlet creates a (stateless) session bean
> and passes in the bulk item. The session
> bean starts the transaction (TX_REQUIRED)
>3 - Sesssion bean creates the entity bean and
> for each element in the bulk item calls the
> appropriate setXXX() method.
>
>As for the scenario of updating the account
>data wouldn't one simply create a new session
>bean which performed that operation, perhaps
>accepting only the relevant parameters and
>calling the appropriate setXXX() methods? I'm
>not sure I'd actually do that or make the session
>bean smart enough to understand how to recognize
>an incomplete bulk item and only call the appropriate
>setXXX() methods.
>
>This, BTW, appears to me to be one motivator for
>the notion that entity beans should "only" be accessed
>via session beans.
________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com
===========================================================================
To unsubscribe, send email to [EMAIL PROTECTED] and include in the body
of the message "signoff EJB-INTEREST". For general help, send email to
[EMAIL PROTECTED] and include in the body of the message "help".
