Cleared Part II/III...99%

[Annie Zhang]

Parag,

You are so helpful! Not just me feel this way

I have another question though:
(1) Did you mention that the travel agents also use a single signon and how ? Did you also mention how the agents represent the customers?
(2) In the class diagram, where did you put the flight layover info, is it in the flight class?

Thanks,
Annie

[Parag Doshi]

Annie,

(1) Did you mention that the travel agents also use a single signon and how ? Did you also mention how the agents represent the customers?

I just mentioned that the travel agent app used EJB client container managed authentication, which is based on trust associations. I think its suffice to mention only this much, as J2EE 2.0 client containers have to support container managed authentication.
I did not explicitly mention about how the agents represented the customers as it was beyond the scope of the assignment but it was stated in the assumption document.

(2) In the class diagram, where did you put the flight layover info, is it in the flight class?

I contemplated it a lot (during my design) so as to where to put the layover information. Then finally, I did not show the layover class or information in the diagram at all. For me, the scope of the layover was only in determining the number of legs in a given flight. It did not hold any other significance beyond that (nor was it used a lot in the use cases. Its only reference was in the prepare itin use case). So, I did not represent the class at all.

HTH
Parag

[Annie Zhang]

Thanks a lot, Parag!

[John Kurtman]

Parag,
Could, please, tell if you choose to save unpaid itinerary to the database, or if you save only after payment. The use cases in assignment are confusing and I am not sure what to do.

Thank you in advance.

Congrats with your great score!!!

[Parag Doshi]

Originally posted by John Kurtman:
Parag,
Could, please, tell if you choose to save unpaid itinerary to the database, or if you save only after payment. The use cases in assignment are confusing and I am not sure what to do.

Thank you in advance.

Congrats with your great score!!!

John,
I had initially started with saving the unpaid itineraries in the database, but, then later on decided to just store them in the session and persisting only the paid itineraries, payment info etc. though, I designed the solution in a way to support unpaid itineraries persistence in the database, if there was a need for it in the future.

The details were explained in the supporting doc.

HTH
Parag

[John Kurtman]

Thank you very much! Your answers are very helpful.

[Dhiren Joshi]

Hi Parag,
Congrats once again for such an excellent score.
I have some queries on some design strategy which I ran into during the designing.
I was going over the Petstore code.
I am confused how EJBAction has been represented by some SCEAs becuase the travel agent client cannot really use the framework part of EJBAction. I am stuck between wanting to use the EJBAction framework implementation becuase it provides flexibility and yet have a low maintainability without code duplication by the TA becuase TA cant use the underlying application services implementation which a web customer can. Does this seem a reasonably design strategy I am following or am I wrong in my assumptions. . .. ?
That I shdnt be following the EJBAction path at all and it wont work in this scenario where web and client application is used and I shd look for different options.. ?

Thanks
Dhiren

[Goutam Bhattacharjee]

If any of you have got a class called: "Equipment" in the business domain model, could you please explain what it is? Is it the aircraft itself, or something else?

Thanks

[kiran]

Component diagram - I read a lot about the different approaches (tier based, package based etc). Finally, didnt follow any of those. I laid the components in logical tiers (though didnt show the tiers in the diagram). The components were stacked left to right, with the leftmost components being the JSPs, Swing components etc and the right most being the DAO, external system etc.

Congrats Parag,
Excellent Score!!!
I have a question regarding the component diagram.
Did you have one component diagram or multiple component diagrams ?

Thanks a lot in advance,
Kiran

[Parag Doshi]

Originally posted by Goutam Bhattacharjee:
If any of you have got a class called: "Equipment" in the business domain model, could you please explain what it is? Is it the aircraft itself, or something else?

Thanks

Hi Goutam,
Sorry for the late reply. Its basically the aircraft. It represents the physical machine (equipment). People have gone to lengths to rename it to 'Plane' or 'Aircraft' too.

[Parag Doshi]

Originally posted by kiran:
Component diagram - I read a lot about the different approaches (tier based, package based etc). Finally, didnt follow any of those. I laid the components in logical tiers (though didnt show the tiers in the diagram). The components were stacked left to right, with the leftmost components being the JSPs, Swing components etc and the right most being the DAO, external system etc.

Congrats Parag,
Excellent Score!!!
I have a question regarding the component diagram.
Did you have one component diagram or multiple component diagrams ?

Thanks a lot in advance,
Kiran

Kiran,
I had only one component diagram with approximately 40 odd components.

HTH
Parag

[Mark Egloff]

Hello Parag

I started just with Part II and now I have some simple questions regarding the class and component diagram. May be you can delight me

Class diagram:
- You mentioned that it has to be technology independent, I wonder why this have to be, is there something writtent that this is requested by SUN or what was the choice?
- How detailed did you model the attributes in the class diagram, did you show only the attributes or only the set & get methods?

Component diagram:
- How did you use there the Stereotypes? Did you use it only for mentioning the design patterns, or did you also use the generic terms as "library", "application"?

- Which type of interfaces did you show there, I saw in some diagrams that people mentioned also there "HTTP" or "JDBC". Did you show only the relevant interfaces which are mentioned in the assingment? What was your approach there?

Thanks

regards
Mark

[liane xu]

Parag,

very good score.

I just wonder whether you use entity beans in your assignment. In terms of database related functions, I prefer using session bean plus DAO, or I could go straight to DAO if I do not care too much about resource management.

what is yout thoughts on it?

thanks

[Parag Doshi]

Originally posted by liane xu:
Parag,

very good score.

I just wonder whether you use entity beans in your assignment. In terms of database related functions, I prefer using session bean plus DAO, or I could go straight to DAO if I do not care too much about resource management.

what is yout thoughts on it?



thanks

Liane,
I used entity beans for my domain objects, I didnt opt for session bean and DAO, mainly because I chose local interface driven entity beans with CMRs/CMP etc. They seemed to be the right choice for my design.
You could go ahead with SB with DAO, but you would have to justify why u went that route and decided to handle the JDBC calls urself.
Its generally not a good idea to call DAOs directly from your client tier, its better to do it from your business tier. That way you can abstract your persistence mechanisms from your business tier and client tiers.

HTH
Parag

[James J Xu]

Originally posted by Parag Doshi:


James,
Thanks for your regards. I am thinking either to go for the web services certification or the PMI. Web services seems more interesting, while PMI has more potential...so torn between the 2

Parag

Parag,

Would you explain what the PMI stands for? Is it Java related or something else?

Happy new year!

James

[Parag Doshi]

Originally posted by James J Xu:


Parag,

Would you explain what the PMI stands for? Is it Java related or something else?

Happy new year!

James

James,
Happy New Year to you too ! PMI stands for Project Management Institute. Its a global body having certifications in Project Management. It would be a good certification to have along with the SCEA.


Parag

[Lucy Hummel]

Hi Parag,

On 3 Dec 2004 you mentioned that you use ValueListHandler.

One question pops up in my mind. How does the Desgin Pattern 'ValueListHandler' realise the Use Case:
'delete a value in the list'.

Is the Design Pattern 'ValueListHandler' only for read? Or can the Design Pattern read and write on the list?

The Design Pattern 'ValueListHandler' provides an 'Iterator'. In general the Interface 'Iterator' provides the method 'remove()'.

So does it mean that the Design Pattern 'ValueListHandler' handles the Use Case
'delete a value in the list'
by the Iterator?

[Marius Huianu]

Parag,

How did you solve the problems with crisscrossings in the component diagram ?

For example, a service locator is referenced by many ejb components or business delegates and that is why there are a lot of crisscrossings. I am going to put a label connected to the ServiceLocator writting in that all
delegates and session beans have a reference to the service locator.

Regards,
Marius

[Justin Chang]

Hi, Parag

I have one question. Did you use EJBController (which is used in the PetStore) ? Or your BusinessDelegate directly talks to SessionFacade of each sub modules ?

Your comments are truely appreciated!


Justin

[Parag Doshi]

Originally posted by Lucy Hummel:
Hi Parag,

On 3 Dec 2004 you mentioned that you use ValueListHandler.

One question pops up in my mind. How does the Desgin Pattern 'ValueListHandler' realise the Use Case:
'delete a value in the list'.

Is the Design Pattern 'ValueListHandler' only for read? Or can the Design Pattern read and write on the list?

The Design Pattern 'ValueListHandler' provides an 'Iterator'. In general the Interface 'Iterator' provides the method 'remove()'.

So does it mean that the Design Pattern 'ValueListHandler' handles the Use Case
'delete a value in the list'
by the Iterator?

Lucy,
Sorry for the late response. My ValueListHandler provided only read-only functionality. I didnt need the 'delete value from list' functionality. Am I missing something here?
I think we are open to provide the implementation of the Iterator. You can have one which can throw an exception if someone tries to remove something from the iterator.
From what I know about this design pattern, ValueListHandlers are mainly for handling huge read only data which needs to be displayed in pages and the rest of the results are cached.

HTH
Parag

[Parag Doshi]

Originally posted by Marius Huianu:
Parag,

How did you solve the problems with crisscrossings in the component diagram ?

For example, a service locator is referenced by many ejb components or business delegates and that is why there are a lot of crisscrossings. I am going to put a label connected to the ServiceLocator writting in that all
delegates and session beans have a reference to the service locator.

Regards,
Marius

Marius,
Yeah, I did just that. It became very complicated to show each component (BD and SFs) interaction with the ServiceLocator.

Parag

[Parag Doshi]

Originally posted by Justin Chang:
Hi, Parag

I have one question. Did you use EJBController (which is used in the PetStore) ? Or your BusinessDelegate directly talks to SessionFacade of each sub modules ?

Your comments are truely appreciated!


Justin

Justin,
I didnt use the EJBController. I had my BDs directly talking to the SFs. I didnt follow the Petstore architecture. It was easier for me to visualise a separate SF for each module and the BDs knowing which SFs would service its requests.

HTH
Parag

[Deepak Pant]

Thanks Parag for sharing this.

I am also following a similar approach.

Somehow I was not able to appreciate the EJBController based design.

I think it is better for a delegate to know about the facade.

[Goutam Bhattacharjee]

Originally posted by Parag Doshi:


Hi Goutam,
Sorry for the late reply. Its basically the aircraft. It represents the physical machine (equipment). People have gone to lengths to rename it to 'Plane' or 'Aircraft' too.

I thought that too! Basically there is nothing else which we could relate it to. But I was looking for somebody to confirm that view. Thanx to Parag, my doubt has been cleared.

[Goutam Bhattacharjee]

Folks,
I guess most of us would agree that the "Nouns" from the domain model should be ultimately designed as Entity beans. I have been thinking the same as well, but a doubt has crept into mind: What about "Nouns" like Segment, Flight & Equipment? Should they be designed as Entity Beans as well? The reason I am having a doubt is, the application does not require to "Create", "Modify" or "Remove" any of these. From the scope of this application, these nouns are really read-only. Under this circumstance, I think Entity beans will be an overkill. Any of you think the same?

[Goutam Bhattacharjee]

Originally posted by Parag Doshi:


I didnt elaborate on the caching implementation in my assignment. Just indicated that it would be done in the business tier. I would imagine that the caching wouldn't be implemented as a stateful session bean, as a SFSB is for a particular client and I wanted the caching to be independent of any particular client.

Parag

I had a look at the J2EE blueprints for ValueListHandler, and there the caching mechanism is in fact implemented as a Stateful Session bean. In this case, the list of flights and available seats is considered as the "State" of the bean and it is these list that are supposed to be cached. The ValueListHandler is suppoed to come into play during searc of flights and seats, and therefore it should not contain any information about the clients identity (such as userID or customerID or mileageAccountNo), as the customer may not be logged onto the system when he/she is searching. However, after Parag says that caching should not be implemented by Stateful Session Beans, I am feeling a bit confused; which way to go.
Parag, can please explain? Am I missing some thing out here?

[Steven Lim]

Hi Guys,

This thread is really great in clearing alot of doubts.
But I have a few questions here :

Understand that the class diagram will normally be technology neutral,
so we will not have things like "Business Delegate" and "Session Facade" in it.

1. So stuff like "Business Delegate" and "Session Facade" will appear in the Component Diagram, but do you specificially write a NEW class(component) as a "Business Delegate" or as a "Session Facade" ?

2. How does one convert from a Class Diagram to a Component Diagram ?
Any reference url/material ?

Regards.
[ January 16, 2005: Message edited by: Steven Lim ]

[ranjeeth kumar]

Hi Parag-
I am a new entry into this group. Got a question
In the class diagram, you mentioned that techonolagy independent. As I understand u didn't specify the ejb's or servlets . But u might have specified classes like Frontcontroller,Business delegate etc? I mean pattern specific classes?

Thanks in advance
Ranjeeth

[Benson Fung]

Hi Parag,

I am still attacking the assginment too. However, I got problem what the format of the documentation should look like. Actually, I have finished all the diagram, however, I am not sure how to write the documentation, e.g. assumption...

Please help

Benson

[Josep Andreas]

Benson,
This link might be usefull:
http://java.sun.com/blueprints/code/adventure/1.0/docs/architecture.html
J

[Sebastiao Santos]

Man,

If I read this before, my score myst be better.

Still going to level III, already delivered level II.

Congratulations.

[Ajith Kallambella]

There's too much information in this thread to be lost, but I'd rather have such useful information in separate and more specific topics. I'm tempted to move this thread over to "Certification Results" forum, but I'll just close it so that test related questions can be discussed elsewhere.

-Ajith