Passed SCEA Part 2/3 with score of 92 !!!

[Yong How, Lim]

Hi All,

Just want to share my joy with all of you.
I have just login to the CertManager to check my score,
and saw that I have passed my SCEA Part2/3

My score is 92.
The following is the Score Breakdown :
=============================
The maximum number of points you could have received is 100, minimum
to pass is 70.
Class Diagram (44 maximum) .......................... 42
Component Diagram (44 maximum) ...................... 38
Sequence/Collaboration Diagrams (12 maximum) ........ 12
=============================

Thanks to everyone here, this forum has been a great help.

Thank God.
[ February 22, 2005: Message edited by: Yong How Lim ]

[ranjeeth kumar]

g8 work

[Deepak Pant]

Congratulations on a wonderful score !!!.

How difficult is Part III ?

Can you throw some light on that ?

[Prasad Kuppa]

Congratulations!

Can you briefly explain your architecture? also, how many classes your class diagram consists, how many sequence diagrams you submitted?

Thanks,

Prasad

[Vagner Freitas]

Congratulations!
Very nice score.
Would you share your experience with us?
Tanks.

Vagner

[Yong How, Lim]

Sorry pple for the late reply.

Some tips here for Part 2 : I concentrate on the Class Diagram first, and have it done till about 80-90% complete, then move on to the Component Diagram.
While doing the Component Diagram, do not be afraid to amend the Class Diagram, also do it till 80-90% complete and move on to the Sequence Diagram. From there onwards, it will be quite straight-forward.

Do not worry about Part 3, if you have done Part 2 with alot of thinking and pondering.

One last point, read and re-read the Requirement document.
I hope the pointers will help.

[subramanian radhakrishnan]

congratulations. Its a wonderful score.

can u share with us the number of diagrams u presented for class /component/sequence/colloboration diagrams.

How detailed was your class diagram [did u explain the methods/propeties as well as the implementaiton choices like local entity ejbs [composite] etc on your diagrams.

Also for component/class diagraqm, i am thinking of folowing Cade/robert's style. But with respect to the assignment requirment that i have, i am wondering how i could explain the other details...since it [cade/roberts] is bit at a high level.

thanks in advance.

[Rashmi Razdan]

Hi Young,
Congratulations.
Im starting with Part2 and need to submit it soon. would u please tell us:
1) which UML tool did u use , and is it good for all 3 types of Digs?
2) I didnt use Cade/simon for the part1 and dont have time to understand it.Do u think its necessary to study that.
Which pattern or strategy / examples would u recommond us for asignemnt as u are having great score.
3) last one ,, ha... Did u use UML2 notations?

thanks,
Rashmi

[Yong How, Lim]

Yes... I have use Cade's book heavily as a guide.
20-30 Classes
15-25 Components
abt 6 Sequence Diagrams

I did not really explain in detail regarding the Component/Class Diagram,
but I did put in a few note here and there in the diagrams.
No explanation on methods and properties, the name that your provide should be sufficiently clear on its purpose, right ?

I had use the Community Edition of Poseidon, quite good.
You can get it at this website : www.gentleware.com

You should know sufficiently well on stuff like Business Delegate, Service Locator.
Take a look at the Blueprint Catalog :
http://java.sun.com/blueprints/patterns/catalog.html
And the Core J2EE patterns :
http://java.sun.com/blueprints/corej2eepatterns/Patterns/index.html

Note, however, it will be an overkill to use to many of the patterns,
please use in moderation, in accordance to the need of the requirement.
Keyword : Satifying ALL the requirements.

No.. I did not use UML2.

[subramanian radhakrishnan]

Thanks for the info.
Even i am using the community edition of Poseidon.
But the icons given to refer a component in a component diagram is a simple rectangle...instead of a rectangular box with two tabs on the uppler left.

Is that an issue wrt UML notation compliance?
Pls let me know how u managed it?

thanks in advance.
subra

[Yong How, Lim]

Hi Subra,

I just stated in the assumption that I am using Poseidon as the tool and the component diagram will come out abit different. To play safe, I have stereotype all components with "component" stereotype.

[Rashmi Razdan]

Hi Yong,

Thanks for the reply.

Rashmi

[Praveen Nagpal]

Hi Yong,

I have some question on the Class/Component Diagrams.

1. Where did you illustrate the J2EE Design Patterns - in the class diagram or the component diagram.
2. I believe, we generally make the Class Diagrams technology independent and an extension of BDM. Did u show any J2EE specific implementations like SB, EB or did u just show things like controller/managers in your Class Diagram.

I'll appreciate if you could elaborate on these.

[Yong How, Lim]

Hi Praveen,

1. I have the Class Diagram as Technology independent, so no J2EE pattern was in the Class Diagram... and J2EE patterns are shown in the Component Diagram.

2. Yes, I feel Class Diagram should be technology independent. I just put in classes that would help to satisfy the requirement. So J2EE stuff (like SLSB, SFSB, EntityBean) is shown in the Class Diagram, not even Managers and Controllers (these are too only included in the Component Diagram).

HTH

[subramanian radhakrishnan]

Originally posted by Yong How Lim:
Hi Subra,

I just stated in the assumption that I am using Poseidon as the tool and the component diagram will come out abit different. To play safe, I have stereotype all components with "component" stereotype.

Thanks for the reply
Subra

[Rashmi Razdan]

Hi Yong,

I had a few more Qs, hope u are still able to participate,
1) whats the use of Equipement in BDM, i cant resolve its use
2) did u handle seat booking procedure as well
3) when it comes to integrating with Frequent flyer,IS
-html scraping and
-direct reading from Oracle only options to us
I don't like anyone of these
Any links or reasonings will be appreciated on how to intgrate from java application to this system.

Thanks in advance
Rashmi

[Yong How, Lim]

Hi Rashmi,

I will try to answer your question without explicitly revealing too much too details.

1. Equipment would be something that the airline use to service their customer.
2. Yes, I did handle seat booking but not in detail.
3. You are right to ponder on each of the options. It does not matter which option you choose, as long as you can justify WHY you choose that option over the other options.

Always keep in mind that you are not acting as a Architect,
you will decide WHY and WHAT to do.
For the HOW it is going to be done, let the developer decide.

HTH

[Sathiya Shunmugasundaram]

Hi Yong,

Congrtas on a great score. Please provide answer to my question if you feel appropriate.

1. Should we provide separate sequense diagrams (two sets) one for Customer in web and another for Travel Agent in Application Client

2. Should we include each JSP and each Swing GUI (Panel??) in the Component diagram?

I know we can support a loosley couped midle tier for both type of clients. I am kind of lost because use cases only tak about the Customer and not the travel agent at all.

Your guidance is really apprecaited.

[Yong How, Lim]

Hi Sathiya,

Answers to your questions :
1. It depends on your design for the clients, if there is significate different in the way 2 clients operates in relation to the application, then use 2 separate sequence diagram. If not, just use a single sequence diagram.

2. The answer to this question is whether you how much details you want to put in the Component Diagram. Also consider that this is a Component Diagram, components are suppose to "hide" certain details, and only exposed the relevant interface so that it can interact with other components.

You need to come to a decision on how to handle the Customer and Travel Agent. Please keep in mind ALL the requirements of the assignment when you start to mind these decision.

I kept a list of decisions and assumptions as list,
and as I goes along, I made revision to this list when I got more insights to those "vague" requirement.
"Vague" requirement will slowly become clear when more assumptions are made.
Do not be afraid to made assumptions, but always justify why you made such a assumption, and revise the assumptions when any of it is in conflict with the scenario.

HTH

[Sathiya Shunmugasundaram]

Thanks for the reply,
Sathiya

[Harry Tan]

Hi How Lim,

your contribution/tips in this thread is very useful and at least I have more ideas starting my assignment.
You said, you focus firstly on class diagram, before moving into component and sequence diagram.

I come out with a classdiagram that focus on EJB-Tier(Session and Entity Beans). But the real problem is the implementation of classes in the clients (Web and App).

In real development I've been using Struts for Web Application and for SwingApplication, I was using several patterns such as Command Patterns.
My questions are:
-Shall I draw the detail of the clients classes or shall I only focus on EJBTier?

-To reduce the amount of classes from ClientTier, can you suggest what I should do in the class and sequence diagram?

-As there are 2 types of clients, how do you draw your sequence diagram?
Can you share your idea on how to simplify the diagrams(Class, Seqence and Component).

thank you.

[Yong How, Lim]

Hi Harry,

Please try understand we can discuss but not give away the answers,
so forgive us if sometimes the answers here in the forum are not straight-forward.

What I did with the Class Diagram is to make it independent of Technology,
there are several advantages in doing it this way. Firstly it focus you on the solving the real issue, and not get carried away with the fancy "bells & whistles" of the latest tech.
Secondly, if there is ever a need to change the choice of the initally picked technology, we can change it easily without affecting the Class Diagram.

Note that these are really good reasons that are applicable in the real-world situations.

Component Diagram is where I put in my Technology related stuff,
including the J2EE patterns.

Sequence Diagram is a sort of the "continuation" of Component Diagram,
"explaining" how the Components interact with each others.

I do not how other people treat these 3 diagrams,
but to me, they are inter-related, they make the picture whole.

Also from my observations of the score break-down so far.
most people got the full 12 marks for the Sequence Diagram,
as Sequence Diagram is usually correct, as it is use to "support" the other diagram.
As you starts to draw the Sequence Diagram,
it will slowly "show" whether you assumption or the other diagrams is correct.
Thus, what I did was to perform minor "tweaks" to my assumptions and other diagrams.

I will start to answer your questions below (without revealing too much details):

-Shall I draw the detail of the clients classes or shall I only focus on EJBTier?

As an "architect", we should not be too concern about details, we need to
concentrate on the "broader" strokes. The thumb of rule is, if an experience developer can understand and implement your design without asking too much question, then you got it just right.
(note too much details will in fact impede the developer)

-To reduce the amount of classes from ClientTier, can you suggest what I should do in the class and sequence diagram?

-As there are 2 types of clients, how do you draw your sequence diagram?
Can you share your idea on how to simplify the diagrams(Class, Seqence and Component).

I am afraid I cannot answer these questions as it can reveal too much,
and also it will very much depend on how you design your ClientTier.

Just need to highlight that there is no restriction on how many classes/components/etc in each of the diagrams,
but note that if you have too many entities in each diagrams,
you may be providing too much details that is necessary.


The best design is one that is simple and straight-forward and that it will satisfy the ALL requirements.
(efficiency and flexiblity are also major factors to consider)


HTH

[Rashmi Razdan]

Yong,

u had posted these two points to one of the qs above :

------------------------
1. I have the Class Diagram as Technology independent, so no J2EE pattern was in the Class Diagram... and J2EE patterns are shown in the Component Diagram.

2. Yes, I feel Class Diagram should be technology independent. I just put in classes that would help to satisfy the requirement. So J2EE stuff (like SLSB, SFSB, EntityBean) is shown in the Class Diagram, not even Managers and Controllers (these are too only included in the Component Diagram).
-------------------
If u are saying in 2) that u identified session and entity bean or javaclass in class dig, doesn't it violate what u say in point 1)..it shud be technolgy independent.

Did u identify any jsp pages in sequnece dig?

Thanks,
Rashmi

[Yong How, Lim]

Hi Rashmi,

Thanks for pointing it out, it is a typo error as I think it quite obvious from the rest of sentence "not even Managers and Controllers"

It should have been :
------------------------
1. I have the Class Diagram as Technology independent, so no J2EE pattern was in the Class Diagram... and J2EE patterns are shown in the Component Diagram.

2. Yes, I feel Class Diagram should be technology independent. I just put in classes that would help to satisfy the requirement. So J2EE stuff (like SLSB, SFSB, EntityBean) is NOT shown in the Class Diagram, not even Managers and Controllers (these are too only included in the Component Diagram).
-------------------

No... I did not have any JSP page in my sequence diagram.

[Kuan Fan]

Hi Yong,

You got a great score..

two questions for you, appreciate for your answer:
1. Do you think the price itinerary use case is necessary? because we can read the unit price for coach and first class when we search the flights in the prepare itinerary use case( also the prepare itinerary use case requires to display the price ), so we can calculate the price just by the number of seat multiple by the unit price. this is why I think the price itinerary use is useless. In my price itinerary sequence diagram, I only simply calculate the price and set to segment.
2. In your component diagram, did you use the lollipop, socket or port for the components. In my component diagram, I use only dependencies between components. I don't show the provide interface(lollipop), required interface(socket) at all.

hope I can get your answer, thank you very much
Kuan

[Yong How, Lim]

Hi Kuan,

The following is the answers to your questions :

1. I think the "Price Itinerary" is definitely needed, first and foremost, it is a Use-Case, which means that it is how the user would actually use it or how the user it expect to work.
Secondly, it is needed when because more than one Uses-Cases refers to it.
In short term, it may look insignificant, but this Use-Case MAY be important later when the customer decide to change the way they PRICE their service.

Always keep in mind the potential of changes the business may encounter later. Although the design may not be TOTALLY flexible to account for every potential change, but it is always good practice factor in the mostly likely change in the near future.
So IMHO, this is what the Price Itinerary is trying to achieve.

2. The Interface is not a MUST, and it depends on your design. If you have component that interact with a external object, then you may like to use it. Otherwise in most case you will not use it. Anyway, components are by definition, suppose to expose their relevant interfaces so that other components can interact with them.


HTH

[Jay Sam]

Hey Ho,

well - I am not wondering about the technical issues - there are other things that somehow worry me.

a) do I have to provide sequence diagrams for every alternative flow ? I hope written text will be sufficient if I provide one sequence diagrams, and then specify how alternative flows will alter the sequence diagram. Example:
"Prepare Itinerary" - there are different flows here, depending on if you formulate a new itinerary in cooperation with the system, or if you formulate a new version of an old itinerary, when you preivously chose to change an itinerary.
b) what about the policies that you chose for seat booking and cancellation of seats ? This pretty much determines how you handle payment, preparation and change of itineraries.
c) what did you chose to do, if the new version of the itinerary was not more expensive, but cheaper than the older one ?
d) I will have 5 sequence diagrams
one for Prepare Itinerary (whether you come from change itinerary or not), 3 for Pay for Itinerary (one coming rom prepare use case, one that starts with listed itineraries, another one to explain how award travel is handled), and one for "change itinerary". Why did you have 6 ?

Regards,

Jay
[ March 15, 2005: Message edited by: Jay Sam ]

[Kuan Fan]

Thanks Yong,

Excellent explanation and great point ...

I was convinced the price itinerary is really necessary. For the component duagram, I will follow Cade's style to show teh dependencies only.

Kuan

[Yong How, Lim]

Hi Jay,

The following is the answers to your questions :
a. IMHO, every alternative flow need to be shown so that we can capture the different scenario that the developer need to handle, which is quite important, because apart from the requirement, this will be the only place in the design that will tell the developer what other scenario the user expects and how to handle it.

b. About these policies, you can make certain assumptions. Make sensible assumptions can make your life make easier.

c. I think you have to re-read the Use-Cases more carefully, it is quite clearly spell out there.

d. On the number of sequence of diagrams, you should have at least the same number of diagrams for each Use-Cases. I choose to show major Alternative Flow as a separate sequence diagram, thus I have more sequence diagrams.


HTH

[Jay Sam]

Hi Yong,

well ad c) - I really tried to find that in the use cases - can you give me a hint ?

There is another issue: did you make use of the timer service ? (if yes, I know what kind of seat-booking policy you have been using)

Regards,

Jay

[Rashmi Razdan]

Hi yong,

thanks for ur reply, I appreciate.
Thats how I had read it initially when u posted it, that "not even Managers and Controllers".
confusion came when
1) I saw somewhere ( may be cade's book )that it had identified entity / session beans in class dig.And u said u folowed that. look how keenly i have read ur comments
2) when i stared making my dig, i didn't find it useful to include my classes as components again to label them as session or entity beans.
And it confused me, as per reqt details we shud identify session or entity bean, jsps etc; where shud i do that???
becos i will be included only paterns and higlevel or generalised view of compoents as in pet-store.

I didn't like cade's componet dig, it has 3 and doesnt use any patterns if i remmeber properly. Then why has sun suggested this book; shud be for sun , for u, why would u say u used it heavily.

Thanks
Rashmi

[Yong How, Lim]

Hi Jay,

I remember somewhere in one of the Use-Case it says that it will refer to the Price Itinerary Use-Case, but it does at what condition.

No, I did not use timer service. (I dont know why you want to have it in the first place)


Hi Rashmi,
For Cade's book, I followed quite closely except the technology portion,
which I feel strongly that the Class Diagram should not contain technology related stuff (as explain earlier in this post).
The notes in Cade's is concise so it let me focus on the real problem.

Another source of the notes I would recommend is to read some of the notes
posted in the this scea_j2ee yahoo group, under the file section there is an enormous amount of material
http://groups.yahoo.com/group/scea_j2ee/files/

Lastly one more piece of advise.
As we are training to become Architects, we should be learning the correct basics of the fundamentals of Software Architects, but always keep in mind what makes one Architect differ from the next Architect is STYLE,
or the way you vary your design within the given boundary.

Just think analogous of the building Architect, they are all constraint by gravity, by material available, by current technlogy, but some buildings are "better" built than others.


HTH

[Rashmi Razdan]

Hi Yong,
Thanks for ur advice , it makes a lot of sense.
in real project scinario, do u really think im going to bother who does what , I will follow my style.

When it comes to the 400$s and clearing exam , it really makes me ask those questions which probably i shudn't. :roll: as one of the other objective means doing what sun prefers.

Thank u,
Rashmi

[Jay Sam]

Hi Yong,

I guess you did use Servlet Filter pattern (as in the petstore example) for signing users on to protected areas.

Well anyhow, I did.

My question: did you mention and show the filter in the sequence diagrams ?
Did you show generation of value objects etc. in the sequence diagrams ?

I wonder if that level of detail is necessary. I would like to mention the servlet filter in the text, and not show it in the sequence diagrams.

Regards,

Jay

[Rashmi Razdan]

Yong,

I understand you used poseidon for sequence digs. Im struk on the mesage.
It doesnt allow to put simply text on the message; while it gives a pattern of stim :action..
Is there anyway to get rid of this combination. If I avoide :action it adds anonymous.
I wonder how did u use it to show messages.

thanks,
rashmi

[Goutam Bhattacharjee]

Hi Yong,
hat methodology did u use to for connectivity between the ejb toer and the credit card verfier system? (TransMaster). EJB specification says we should avoid socket connection from an ejb. It looks to me that we can treat TransMaster as a web-service (since it has an API in xml-rpc) and then let the ejb layer access this web service. Please opine whether this assumption is correct.

Thanks
gb

[Rashmi Razdan]

In case it helps , chk section ,Asynchronous Messaging Module Implementation in the url :
http://java.sun.com/blueprints/guidelines/designing_enterprise_applications_2e/sample-app/sample-app1.3.1a3.html.
And let me know if it helps.

rashmi