SCEA Part II - Problems to Understand the Domain Model

[David Neto]

My first doubt: Is it possible to discuss about this in this forum?

[Jeanne Boyarsky]

Maybe. The relevant part of our rule is:

Okay, here is the deal. If your question/post has any verbatim reference to assignment text, it will be nuked. It will be deleted if you used some specific terminology straight from the assignment - use case names, subsystem names, interview excerpts etc. General discussion about flight reservation system is fine, and so is the use of common terms like flight, leg, segment etc. It is very difficult to draw the line, so I will be using my own judgement.

There will be no email/notification sent individually. If you notice your thread vanished, just assume that it had some content that violated or had a potential to violate the copyright agreement.

[David Neto]

In the domain model,

1) Can I define the multiplicity and navegability of the classes that doesn't have this defined?

2) Can I define a base classe for classes that are the same kind and make the relationship's with the base, eliminating the relationship with the especialized classes ?

3) Have I to reference all the domain classes in my diagrams?

4) Have I to put attributes in the domain classes?

[Sadanandam Kurapati]

Hi David,

I am not sure why we need to define the domain model for SCEA Part II assignment. The assignment itself provides the domain model of the problem. If you are asking how to model the class diagram from domain model diagram, then please find my answers.

1) Can I define the multiplicity and navegability of the classes that doesn't have this defined?

Yes, you can define as long as it make sense for your solution.

2) Can I define a base classe for classes that are the same kind and make the relationship's with the base, eliminating the relationship with the especialized classes ?

Yes, you can and it is always good idea to do that.

3) Have I to reference all the domain classes in my diagrams?

Yes, we should not drop anything from domain model. Remember, class diagram is the extended version of the domain model with more details.

4) Have I to put attributes in the domain classes?

Not sure but it will be good idea to define the attributes.

Note: Please remember that we need to stick with domain model. You can change around 10% to 15% but remember to provide the supporting points for that deviation.

Hope this information is helpful.

Regards,
Sadanand

[David Neto]

If I have a use case description like this:

1) Customer search for all products offers;
2) System responds with all offers;
3) Customer select a offer and place a bid for it;
4) System record the bid for the offer.

Can I consider, for 1 e 2, that the customer is another system that sent a JMS message for my system and i respond with another JMS message (JMS Request-Replay)?

Can I consider, for 3 e 4, the customer sent a JMS message for my system with the bid and i record the bid.

1 e 2 happens in a different time and transction that 3 e 4.

Is a right thinking?

[David Neto]

Sadanand Kurapati wrote:Hi David,

I am not sure why we need to define the domain model for SCEA Part II assignment. The assignment itself provides the domain model of the problem. If you are asking how to model the class diagram from domain model diagram, then please find my answers.

1) Can I define the multiplicity and navegability of the classes that doesn't have this defined?

Yes, you can define as long as it make sense for your solution.

2) Can I define a base classe for classes that are the same kind and make the relationship's with the base, eliminating the relationship with the especialized classes ?

Yes, you can and it is always good idea to do that.

3) Have I to reference all the domain classes in my diagrams?

Yes, we should not drop anything from domain model. Remember, class diagram is the extended version of the domain model with more details.

4) Have I to put attributes in the domain classes?

Not sure but it will be good idea to define the attributes.

Note: Please remember that we need to stick with domain model. You can change around 10% to 15% but remember to provide the supporting points for that deviation.

Hope this information is helpful.

Regards,
Sadanand

Sadanand Kurapati, thanks for your contrition!

I am not interest in define a model, but complete some things that i think are incomplete like : multiplicity and navegability (some classes not have this define), 3 classes represeting products whitout a base class.

[naresh kumar nand]

I think I haven't get the problem exactly. Why do you require JMS message for 1 & 2 scenarios. Is it mentioned to use JMS? If both Customer and System are using same database.Why can't we use entities and do a fetch to the database. If 1000's of customers do a search for all products at the same time then how this be handled in JMS.

If they are two different applications and having different databases then WebServices may come into picture.

[Sadanandam Kurapati]

Hi David,

Somethings in the domain model and the problem statements are left intentionally and it is up to us to understand the system and fill the gaps. One problem can be interpreted in different ways, but only thing I recommend is to document whatever the assumptions you made clearly.

To answer straight to your question, yes you can add multiplicity and navigability. And also you can design the base class/interface. Make sure you document everything.

Regards,
Sadanand

[David Neto]

Sadanand Kurapati wrote:Hi David,

Somethings in the domain model and the problem statements are left intentionally and it is up to us to understand the system and fill the gaps. One problem can be interpreted in different ways, but only thing I recommend is to document whatever the assumptions you made clearly.

To answer straight to your question, yes you can add multiplicity and navigability. And also you can design the base class/interface. Make sure you document everything.

Regards,
Sadanand

Thanks Sadanand!

[David Neto]

kumar naresh wrote:I think I haven't get the problem exactly. Why do you require JMS message for 1 & 2 scenarios. Is it mentioned to use JMS? If both Customer and System are using same database.Why can't we use entities and do a fetch to the database. If 1000's of customers do a search for all products at the same time then how this be handled in JMS.

If they are two different applications and having different databases then WebServices may come into picture.

Thanks kumar!

I am try to understand yet.

I am assuming that the customer is another system that send JMS message to get the offers (1 e 2) and after choice the offer make a bid (3 e 4) for it by JMS again.

The problem is that in the use case text is not explicit the use of JMS or WebServices or another system.
It just define the actor Customer.
But in other section is define that the company is selling your products in auction marketplace and the comunication is by JMS.

[priam dutta]

Hi,
I have some questions regarding the component/ sequence diagram:
1) In any application from Homepage if we click any search / create/ edit/ update page link then it opens that page from where we start other operations. Now question is in your assignment have you shown any flow to display how any page is getting generated from Homepage.
For example as per the above after clicking search link from Homepage how that Customer-Search page will generate for that have you shown any diagram? Because it may possible that in search page you have multiple dropdown with various values (so that user can select that data for search) and to populate that value it’s require to go through java flow. So do we need to show that value.

Or say if you have to open a product-offer creation page from Homepage. Now have you shown the flow how the product-offer creation page is opening after clicking the link from Homepage. Because in your order creation page you may need to display some pre-populated data (like product list, product type list etc) which needs to come from database. So do we need show any component/ sequence diagram for that or you can start your diagram from order-creation page directly.

[Sadanandam Kurapati]

Hi Priam,

It is always good to show the information(form data) population in sequence diagrams. In your specified example, you can have something like this sequence.
User --(search)-->home.jsp ---(getProducts)-->SearchControler.java--(controler to Manager to DAO etc)->
search.jsp---(search, dropdown selection)-->SearControler.java---- etc-------

Yes, the sequence diagram will be big but will show more granular information.

Make sure all of the Manager, DAO etc methods(data population methods) are listed out in class diagram. In component diagram we just list the jsp and classes so no need to worry about it. Most importantly all of the assignment deliverable(class, component etc) should be consistent and convey the solution as unit.

Hope this will answer your question.

Regards,
Sadanand