• Post Reply Bookmark Topic Watch Topic
  • New Topic
programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other Pie Elite all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Campbell Ritchie
  • Tim Cooke
  • paul wheaton
  • Jeanne Boyarsky
  • Ron McLeod
Sheriffs:
  • Paul Clapham
  • Liutauras Vilda
  • Devaka Cooray
Saloon Keepers:
  • Tim Holloway
  • Roland Mueller
Bartenders:

Passed Part 2/3 with 100

 
Greenhorn
Posts: 28
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator


Thanks for you help. So in your design it is possible for a flight to have a list of eqiopments. Hence, you changed the multiplicity between Flight and Equipment as well. Am I worng?



Nope, Flight/equipment was still 1-1. That last post was confusing as my whitespaces didnt work. In the attempted diagram, think two flight instances each with there own equipment and that is what I meant.

Sorry for the confusion,

Matt
 
Ranch Hand
Posts: 92
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Thanks Matt,

Could you help me with the following please? I have asked the same question on Giri post but didn't receive a response yet

What dose the system return for the following trip A---B---C when the user enters A as the departure city and C as the destination city?
For my current design, based on the BDM, I have two segments A---B and B---C. Each segment has its own flight as follows:
Segment A---B has the associated flight F_AB
Segment B---C has the associated flight F_BC
According to �Prepare Itinerary�, a list of departure flights and return flights will be returned by the system.
How can I satisfy this requirement?

Also, can you please help me with the following topic:
How to handle security for the rich client application?
 
Matt Rea
Greenhorn
Posts: 28
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator


Thanks Matt,

Could you help me with the following please? I have asked the same question on Giri post but didn't receive a response yet

What dose the system return for the following trip A---B---C when the user enters A as the departure city and C as the destination city?
For my current design, based on the BDM, I have two segments A---B and B---C. Each segment has its own flight as follows:
Segment A---B has the associated flight F_AB
Segment B---C has the associated flight F_BC
According to �Prepare Itinerary�, a list of departure flights and return flights will be returned by the system.
How can I satisfy this requirement?

Also, can you please help me with the following topic:
How to handle security for the rich client application?



If you look at any airline site, I use the Australian airline Qantas for example. You can with Qantas do a booking online and see the process and obviously quit when it comes time to pay I found this research a great way and found alot of the requirements in FBN are very relevant in real world airlines.

In terms of a list of departure/return lights a airline may have a number of different combinations of getting from A->C. In your above example B may be a different airport for example. So the user has lots of differnt choices they could make in some cases.

Your second question, Rich Client security. Depends on how your rich client connects. I think your post says directly to business tier. I think the following link I found helpful, especially Parags first comment.



web page

Matt
 
Mark Cave
Ranch Hand
Posts: 92
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Thanks a million Matt,

I will take a look at both resources you suggested and see how it goes.
 
Ranch Hand
Posts: 208
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Thanks, Matt. Could you let me know how to show composite entity bean in the component diagram? My thought is to show dependency between one entity bean and another entity bean. Is it right? Except for the stereotype, I realize that some components in my component diagram are the same as some classes in my class diagram (e.g. Account, ContactInfo, Address). What is your opinion on that?
 
Mark Cave
Ranch Hand
Posts: 92
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Why to have a ShoppingCart for flight reservation? I do not think this is the right way to solve the problem.
 
Matt Rea
Greenhorn
Posts: 28
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator


Thanks, Matt. Could you let me know how to show composite entity bean in the component diagram? My thought is to show dependency between one entity bean and another entity bean. Is it right? Except for the stereotype, I realize that some components in my component diagram are the same as some classes in my class diagram (e.g. Account, ContactInfo, Address). What is your opinion on that?



I agree with your thoughts completely. Obviously you have the composite entity object and its dependant objects and these components can be the same as classes in your class diagram. I used notes to also highlight patterns as my stereotypes were very generic.

How you persist the data and other patterns such as transfer object are relevant in this area as well.
 
Greenhorn
Posts: 16
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
congratz ,for ur success!

do u like to shed some lights on how u connect and show in diagrams the Transmaster and Mileage

How you show about transaction in diagrams or just write in assumption ?

for flight/equipment/seat is read only so do we have to implement this in BMP/DAO for faster access while I am implementing itinerary /segment as CMP?CMR

If I use aggregation or composite entity for itinerary/segment then my class diagram
should display aggregation , so does it mean i am changing the BDM ?
 
Greenhorn
Posts: 29
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Great Score..Congrats..

Question : I am going to appear for SCEA II exam and I am having doubt in Sequence diagram. Pls explain in detail


The Sequence diagram should start from JSP/Swing program or we can start from business objects. Basically I am not sure about this and I need more clarification regarding this. Without knowing this I can�t start the design also.

Why I am asking this is, I have seen in some books they are starting from JSP and in some books they are starting from business objects. So, pls want some good Answer.

Thanks in advance to all.
 
Matt Rea
Greenhorn
Posts: 28
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator


congratz ,for ur success!

do u like to shed some lights on how u connect and show in diagrams the Transmaster and Mileage

How you show about transaction in diagrams or just write in assumption ?

for flight/equipment/seat is read only so do we have to implement this in BMP/DAO for faster access while I am implementing itinerary /segment as CMP?CMR

If I use aggregation or composite entity for itinerary/segment then my class diagram
should display aggregation , so does it mean i am changing the BDM ?



There has been lots of discussion about the mechanics of connecting to the credit and mileage systems. I think design patterns such as DAO and transfer object are as relevant to these interface as any other. In terms of diagrams I did include a basic reference to these interfaces in the class diagram and more detail in the component diagram given that is where my pattern use was highlighted.

Transactions were detailed in my assumptions document.

Sure in terms of searching for flights/seats that met the user criteria fast lane reader is a very relevant pattern to consider for this assignment. My design choice was to use BMP/DAO for all persistent data access, not just search operations but persisting itinerary bookings. I would go so far as to assume flight/equipment/seat are all completely read only, there must be some method for the application to keep track of what seats have been booked for example on a flight.

My class diagram made use of aggregation, exactly because of my use of the composite entity pattern. I did not change my BDM to reflect this change at all. The only change to the BDM I made was cardinality between segment/flight as mentioned earlier in this thread... alot

Hope that helps

Matt
 
Matt Rea
Greenhorn
Posts: 28
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator


Great Score..Congrats..

Question : I am going to appear for SCEA II exam and I am having doubt in Sequence diagram. Pls explain in detail


The Sequence diagram should start from JSP/Swing program or we can start from business objects. Basically I am not sure about this and I need more clarification regarding this. Without knowing this I can�t start the design also.

Why I am asking this is, I have seen in some books they are starting from JSP and in some books they are starting from business objects. So, pls want some good Answer.

Thanks in advance to all.



Hello,

I wasnt sure about this myself for a while both because of supporting both GUI's and just general confusion. I did the following on my sequence diagrams:
- Started with a user (Actor)
- A generic FUI object next. The message itself tells you what operation you are doing. If you have a object for every seperate page the diagram gets massive (I know cause I did this on my first draft).
- I also did a generic MVC Framework object as I didnt think I need to show the detailed of how the MVC pattern works.

The above approach supports both web based and swing UI with no change.

There was one sequence diagram where I didnt do the above. Price Itinerary started from a business object in my case. I wasnt sure about this one myself so I used notes to describe entry point and how it fitted in with the other diagrams. In hindsight I could have done it the same as the others but it didnt seem to matter.

Hope that helps,

Matt

Matt
 
sys alley
Greenhorn
Posts: 16
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
>My class diagram made use of aggregation, exactly because of my use of the composite entity pattern.

thanks for your reply. You told that you used aggregation for composite entity . why not use composition instead of aggregation. But in Sun Blue print they showed compostie entity with composition not with aggregation.

Can you explain this ?
 
Greenhorn
Posts: 13
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hi Matt..
Thats some awesome score there!!! Hats off to ya..
I am still preparing for my part 1 exam and hope that this thread would still be alive by the time i complete it. It is really nice of you to answer all the queries of ppl here though these doesnt make much sense to me rt now
 
Greenhorn
Posts: 8
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

Originally posted by Matt Rea:


Yes, I including a Cart class in my class diagram. I also included the Cart in the component diagram where it was relevant. My class diagram was completely technology independant. There were a number of classes that appeared in my component diagrams such as session facades for one example.

Matt

[ June 22, 2005: Message edited by: Matt Rea ]



Hi Matt,

did you discuss when to persist objects i.e. when itineraries are stored in a database. ShoppingCart sounds like a non-persistent data?

Mark
 
Matt Rea
Greenhorn
Posts: 28
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator


did you discuss when to persist objects i.e. when itineraries are stored in a database. ShoppingCart sounds like a non-persistent data?



Hi Mark,

Yes, object persistence part of my solution. My Itinerary persistence used the same design as the my customer objects. Patterns such as composite entity , transfer object and DAO I found very useful in this area. The Sun blueprints site provides all you need to both understand the pattern but also how to use it.

My shopping cart was, fundamentally, used to persist session data between screens during the prepare itinerary use case for example.

Matt
 
Greenhorn
Posts: 12
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Congratulations!

I like your thoughts on the Segment - Flight. How did you represent the one way or two way?
My thought was from source to destination it is one segment and so a round trip itinerary has two segments, otherwise it is just one segment. But each segment can have one or many flights.

Also did you consider customer buying many tickets in a single itinerary? In such cases how to map the frequent flyer mile? Is it per customer or per passenger?

Thank you so much
 
Greenhorn
Posts: 16
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Congratulations!!!
 
Matt Rea
Greenhorn
Posts: 28
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator


Congratulations!

I like your thoughts on the Segment - Flight. How did you represent the one way or two way?
My thought was from source to destination it is one segment and so a round trip itinerary has two segments, otherwise it is just one segment. But each segment can have one or many flights.

Also did you consider customer buying many tickets in a single itinerary? In such cases how to map the frequent flyer mile? Is it per customer or per passenger?

Thank you so much



Hi Vishwa,

I didnt really distinguish 1-way or 2-way. Obviously it is a criteria by with you search for flights when building your itinerary but in terms of my iterpretation of the BDM there was no special handling of a return flight over a 1 way flight. Your description of how you want to setup the segments and flights is perfectly okay and is essentially the same approach I took.

Customers buying multiple seats. My view is the customer is paying for the itinerary. So for me I think per customer was the way to go and mapping to paying by credit of FreqFlyer is the same as if it was a single seat on one segment. Document your assumptions/Decisions at all levels and you will be fine.

Matt
[ July 05, 2005: Message edited by: Matt Rea ]
 
Greenhorn
Posts: 23
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hi Matt

I'm finishing the project and i hope to upload next days but i have a doubt on price itinerary use case:
In prepare itinerary use case we have:
"System responds with the selected flight priced and alternative flights if less than selected and within one hour of departure and return times"
In price itinerary use case, we have:
"System calculates the price of each segment of the selected itinerary and returns the priced itinerary"
The price of each segment is already calculated in prepare itinerary use case,is it called once again,only for adding the prices together ?
Thanks
Albert
[ July 05, 2005: Message edited by: Albert Maurucier ]
 
Greenhorn
Posts: 9
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hi Matt,

Did you mention anything about load balancing the two web servers? How did you handle it?

Thanks in advance,

Steven
 
Matt Rea
Greenhorn
Posts: 28
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator


Hi Matt,

Did you mention anything about load balancing the two web servers? How did you handle it?

Thanks in advance,

Steven



Hi Steven,

I did mention load balancing of the web servers in my assumptions/design documents.

In the real world, I have worked with some pretty big J2EE architecture over the years and most recently a cluster of 3 big BEA application server machines and 4 web servers in front. The web servers are load balance by a hardware load balancer, in this case a Cisco Director. That is a pretty standard approach I have seen and used alot.

Matt
 
Matt Rea
Greenhorn
Posts: 28
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator


Hi Matt

I'm finishing the project and i hope to upload next days but i have a doubt on price itinerary use case:
In prepare itinerary use case we have:
"System responds with the selected flight priced and alternative flights if less than selected and within one hour of departure and return times"
In price itinerary use case, we have:
"System calculates the price of each segment of the selected itinerary and returns the priced itinerary"
The price of each segment is already calculated in prepare itinerary use case,is it called once again,only for adding the prices together ?
Thanks
Albert



Hi Albert,

Read the requirements really carefully, there are areas where we could do with some more details however assumptions have to suffice.

A couple of thoughts:
- When you select the initial flights and get the alternative flights and prices you havent selected seats yet....
- what class your seat in will effect your pricing.
- You may have selected different combinations of initial and alternative flights for the final itinerary that needs pricing.

I made some assumptions to constrain my scope and provide the detail I felt I was missing in this case.

Hope that helps.

Matt
 
Albert Maurucier
Greenhorn
Posts: 23
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Thanks Matt

I had already, taken in mind what you said but... this solution seemed to me too irrealistic, my approach was different,I have made other assumptions:
-customer selects class at the beginning of the use case. At seat selection time, system displays only available seats corresponding to the class customer selected.
-System displays "packaged flights", customer can't select individual flight in any connection is necessary, so, the displayed price is for this package (or option: inbound or outbount trip), segment price is calculated...
I had never seen a reservation web site displaying all possible prices for a given flight.
I'll try to refine my assumptions...Thanks again Matt.
Albert
 
Steven Dolan
Greenhorn
Posts: 9
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Any resources, you recommend, to read more about load balancing?
Thanks

Hi Steven,

I did mention load balancing of the web servers in my assumptions/design documents.

In the real world, I have worked with some pretty big J2EE architecture over the years and most recently a cluster of 3 big BEA application server machines and 4 web servers in front. The web servers are load balance by a hardware load balancer, in this case a Cisco Director. That is a pretty standard approach I have seen and used alot.

Matt



What do you think are important points that one might forget to mention in the assignment? I am as well about to submit my assignment but I have the fealing that something is missing. In my current document, the assumptions are with the class and component diagramson on the same page.
 
Greenhorn
Posts: 2
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hi Vishwa,

I do not mean to confuse you as I am confused myself, but I do not agree with your definition of segment with respect to FBN. From the BDOM an itinerary has 1..* with segment. If segment was simply defined as source to destination then any itinerary would have at most 2 segments, depending on if it was a 1-way or a round trip. But from BDOM we can have many segments which means the definition of segment is not simply source--> destination but is a non-stop flight from source-->destination.

With this definition everything falls in place as per the BDOM.
itinerary 1..* segment
segment 1..1 flight

Just a thought.......what do you guys think??

Anush
 
Ranch Hand
Posts: 32
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Matt,

If you're still reading, I'd like to ask again about the Flight-Segment multiplicity.

In the approach that you explained in great detail (Segment 1 - 1..* Flight, the rest unchanged) it is possible to navigate from a "flight" to the "customer", because there will be only one-to-ones or many-to-ones along the way! That means each flight must have a unique "Customer". I just can't imagine how this can be the case.

This can only make sense if "Itinerary" is understood as abstract "journey", not associated with a particular customer, which again contradicts the given BDOM. Could you please comment on this?

Thnx,

Mitry
[ July 12, 2005: Message edited by: Hitry Mitry ]
 
Greenhorn
Posts: 8
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hiltry

Try to validate the class diagram by an object diagram...Can a given itinerary contain more than one segment for a given flight ? More simpler: you purchase a trip, for this trip, can you book more than once the same flight for the same passenger?

Marcel
 
Hitry Mitry
Ranch Hand
Posts: 32
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I think I understood.

The key point here is that classes can be inserted.
That makes one's life a lot easier !
 
Ranch Hand
Posts: 101
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hello Mitry . If you understand it , explain me ... please
 
Ranch Hand
Posts: 2108
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
you are baaaad.... excellent!!! congrats!
 
Greenhorn
Posts: 5
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hi,
This forum is really helpful and I got an question while attempting for part 2.

I am confused about where to save Iternory when user presses confirm and save. Is it to be persisted in db or to be saved temporarily.

If saved temporary, then how to handle change iternories, because that use case tells that system load list of iternories.

Also I am not sure how seat avalibility works. Because user checks for seat avalibility at very early stage in prepare iternory. After that user has to go through few more screens till final payment happens. During this time, all seats might have been full, though there might have been few seats during prepare iternory. Not sure how to handle this?
Any ideas ?
Thank you very much
 
Greenhorn
Posts: 18
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Matt,

Did you change the "Seats" from BDOM with "Seat" ?

Regards,
Marius
 
Jose Jim�nez
Ranch Hand
Posts: 101
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
After read this forum I have a dubt about UML until (For exameple between aircrft and equipment).

My definitions:
Aircraft = concrete airplane (serial number, milesTotal, ... )
Equipment = Setting of aircraft ( type (example Boeing 737) , number of
passangers, ... )

If i think in data base nivel, one aircraft could have several equipment for different flights . In my uml class diagram I show it:
Aircraft 1 <-- * Equipment

If i think in object in memory , one equipment is setting for one aircraft in each flight.

Aircraft 1 <-- 1 Equipment

What's the correct ? Could explain me?

Thanks
 
Jose Jim�nez
Ranch Hand
Posts: 101
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
It referred to Class Diagram .

I wait for answer ...
 
Matt Rea
Greenhorn
Posts: 28
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator


Matt,

Did you change the "Seats" from BDOM with "Seat" ?

Regards,
Marius



Hi Marius,

I had "Seat" in my BDM and class diagram however looking back I didnt highlight this very small change from the BDM in my documentation, which probably means I did it by accident. I dont think it matters in this specific case as the multiplicity is the important thing. A customer books 1..* seats on the specific equipment etc.

Matt
 
Matt Rea
Greenhorn
Posts: 28
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator


After read this forum I have a dubt about UML until (For exameple between aircrft and equipment).

My definitions:
Aircraft = concrete airplane (serial number, milesTotal, ... )
Equipment = Setting of aircraft ( type (example Boeing 737) , number of
passangers, ... )

If i think in data base nivel, one aircraft could have several equipment for different flights . In my uml class diagram I show it:
Aircraft 1 <-- * Equipment

If i think in object in memory , one equipment is setting for one aircraft in each flight.

Aircraft 1 <-- 1 Equipment

What's the correct ? Could explain me?

Thanks



Hi JJ,

I went with a 1->1 relationship in this area myself. My logic, even though different aircraft can have different configurations, each instace of a aircraft has only a single configuration.

I ended up going for a more inheretence model approach when thinking of equipment and aircraft in my class diagram, one of the reasons I seem to have more classes than I have read other people got. I did however think about abstracting the setup of a aircraft away from the equipment class heirarchy into a configuration object.

hope that helps

Matt
 
Marius Huianu
Greenhorn
Posts: 18
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Thank you Matt !
 
Ranch Hand
Posts: 79
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hi, Matt.

How do you address alternatives flow in your sequence diagram?
Or you just mentioned in your assumption on how this can be approached?
 
Matt Rea
Greenhorn
Posts: 28
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator


Hi, Matt.

How do you address alternatives flow in your sequence diagram?
Or you just mentioned in your assumption on how this can be approached?



Both really. I have the alternate flows in my sequence diagrams where relevant. For example in Prepare Itinerary near the end before confirm itinerary I add a section for each alternate flow, nothing spectacular, basically just referencing the add login and profile use cases. I added notes in these areas to be really clear about what I was doing.

I also have some details in my assumptions around a few inconsisencies with the use cases alternate flows I thought helped clear up any unknowns etc.

Hope that helps,

Matt
 
Ranch Hand
Posts: 202
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

Originally posted by Matt Rea:


Hi David,

I think there are any number of approaches and solutions to the Itinerary/Segment/Flight etc BDM issue. You just need to be clear in your own mind on how you apply it to the problem domain and constrain your solution with relevant assumptions. My way is only one approach and given the amount of discussion on the list over the last few years I have seen a number of approaches that are all valid and got very good marks.

I changed the BDM to fit with my solution making Segment and Flight 1 - 1..* Given I have tried to explain this a few times, rambled alot and have probably confused everyone more I will try to highlight a real life example I found very relevant and enlightenting to validating my model.

I took a flight from Melbourne, Australia to Washington DC, USA and lets just stick to one way. I did this in real life, took 30 hours which was hell but that is not the main point here

Itinerary had 2 Segments.
- Segment 1: Melbourne to San Fransisco with flight number 123.
- Segment 2: San Fran to Washington DC with flight number 456.

Segment 1 was where I didnt like the original BDM. Basically Melbourne to San Fran was really Melbourne->Sydney->San Fran. Some passengers only went form Melb->Sydney as overflow on domestic flights I guess and some passengers joined in Sydney to go on to San Fran. We actually changed aircraft type in Sydney but kept the same flight number. I described this scenareo in detail in my assumptions/design document to defend my decision to change the BDM ever so slightly and the model was applied.

Segment 2 was a nice and simple so no issue there with the old BDM.

In thinking about scenario 1 I just didnt like the way the original BDM handled it. That doesnt mean mine is the only solution. Leaving the BDM as is and coming up with alternative solutions could be 100% correct. I am pretty sure my good mark came down to fully documenting my assumptions and design rather than this approach being the only valid solution.

David, hope that help... or I have just confused everyone more

Rgds,

Matt



Matt, i am not sure if you can still answer this question. In your case when you had changed the BDOM from Segment-Flight (1-1) to (1-M), then shouldn't the flight number change as well.

Is it possible to have same flight number for two flights ? I-e a flight Melbourne to Sydney is 123 and Sydney to San. fransisco is 123. Why is that ?
Can you explain this ? Or did you include this assumption that two flights can have the same flight number?
 
Create symphonies in seed and soil. For this tiny ad:
Smokeless wood heat with a rocket mass heater
https://woodheat.net
reply
    Bookmark Topic Watch Topic
  • New Topic