Business logic in EO, VO - design advice required

Hi all,
I'm looking for some design advice on the best way to approach this issue - or in fact advice that I'm making an issue out of something where it doens't need to be !
Lets say I have a single entity object called UsersEO. I have two view objects called NewUserVO and ExistingUserVO. I use the NewUserVO just for inserting new records and the ExistingUserVO for modifying existing records. When users are editing existing users, I need to provide a checkbox that indicates that when the record is saved, their password needs to be re-generated and emailed out to the user.
I want to include the check of the "GeneratePassword" attribute while processing the rest of my user business logic, in the doDML method of UsersEOImpl. From here I will call a database procedure that handles changing the password and emailing the user.
Initially I created a transient attribute "GeneratePassword" in ExistingUserVO but then to access this from within the UsersEOImpl.doDML would require me getting the AM from the transaction, and getting the current row of the ExistingUserVO. I believe that this is bad practice to access a VO from within a EO ?
Is my only option here to create the transient attribute "GeneratePassword" on the UsersEO and then include in the ExistingUserVO but not the NewUserVO ? That way I can easily access the "GeneratePassword" attribute from with the doDML without have to accessing the VO.
If I have 10 different VO's that require different attributes, it just seems strange to add 10 attributes to the underlying EO and then only include the relevant entity attribute in each VO - or is this exactly what I should be doing ?
On a slightly different note, but similar theme - if I had a "VOTransaction" attribute in my EO and I included this in each VO created from the EO - how would I set different values in this attribute for each VO so that within the EOImpl I would know which VO was triggering the entity validation ??
Many thanks for your help !
Cheers,
Brent

>
If I have 10 different VO's that require different attributes, it just seems strange to add 10 attributes to the underlying EO and then only include the relevant entity attribute in each VO - or is this exactly what I should be doing ?
How about creating a BaseVO which extends EO (including transient attributes for password change and voName/Type detail ) that provide a default value for voName/Type attribute and all other VO extending the BaseVO and overriding that attribute setter to specify the name/type?

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could you please explain your usecase.
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yeah sure. people will do.
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Put business logic in backend database layer.
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Hello everyone!
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Just to expand on Bala's answer, it depends on how your application is architected.
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Business logic in PL/SQL?

Hello,
I am designing a 3-tier, web-based intranet application for my client. It's going to be a WebSphere portal app with Struts, running on Oracle 8.1.7.
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This unusual (?) choice in my humble opinion leaves me
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I have seen code implementations which took significant database processing time where the entire solution could have been done without the database at all.
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Separating presentation from business logic.

I recently wrote an article on how to separate JSP presentation from the business logic without a complicated framework.
http://labs.revision10.com/?p=16
I haven't seen this exact approach taken before, but believe it works fairly well for most simple web applications. Applications which tend to attract many developers to PHP do to its simple architecture.
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Here goes the answers to your question. (according to my knowledge)
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I was thinking the same thing, but don't have a
successful experience to validate my gut feelings.
Here's my only suggestion (which dubwai could
hopefully confirm or correct): write your entity
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just the getChildren() type of methods and build the
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When the
GUI asks for an object in the getData() call, hand
them a subclass object, but don't let them know it.
In other words, have the method "public DataClass
getData()" return a SubDataClass object. The caller
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object, but lazy-loading awareness will be built
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of. (Only classes that have been tagged 'final' or
have 'final' public methods would be beyond this
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Foo (e.g. bars) incrementally after the Foo is
returned to the caller. Often you can load the
bars
in the time it takes the user to click around to
the
point where they are needed or at least be partly
done. This will make the app seem very fast to the
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you didn't load the chidren) and then the bars
really
quickly (because you loaded them during user
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Urgent: how to really seperate business logic class from data access class

Hello,
I've this problem here on my hand and i really need help urgently. so please allow me to thank anyone who replies to this thread =)
Before i go any futhur, let me present a scenario. this will help make my question clearer.
"A user choose to view his account information"
here, i've attempted to do the following. i've tried to seperate my application into 3 layers, the GUI layer, the business logic layer, and the data access layer.
classically, the GUI layer only knows which object it should invoke, for example in the case above, the GUI would instantiate an Account object and prob the displayAcctInfo method of the Account object.
here is how my Account class looks like:
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that being the case, when i want to retrieve back account information, how do i go about retrieveing the information on the customer? should my data access class have knowledge on how the customer is being programmed? ie setName, getName, setAge, getAge all these methods etc? if not, how do i restore the state of the Customer object nested inside?
is there a better way to archieve the solution to my problem above? i would appriciate it for any help rendered =)
Yours sincerely,
Javier

public class AccountThat looks like a business layer object to me.
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Business logic in EO, VO - design advice required

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