• 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
  • Jeanne Boyarsky
  • Ron McLeod
  • Paul Clapham
  • Liutauras Vilda
Sheriffs:
  • paul wheaton
  • Rob Spoor
  • Devaka Cooray
Saloon Keepers:
  • Stephan van Hulst
  • Tim Holloway
  • Carey Brown
  • Frits Walraven
  • Tim Moores
Bartenders:
  • Mikalai Zaikin

Post-Condition for "Change Itinerary"

 
Ranch Hand
Posts: 223
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I don't understand the Post-Condition for "Change Itinerary". Why does the unpaid itinerary only contain the city, flight#,... of the departure flight and city, flight#,... of the return flight? What about the city of destination? What if I have a one-way itinerary only?

D.
 
Ranch Hand
Posts: 79
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Please look at the basic flow of the change itinerary again.

* Customer selects the SEGMENT to change.

Therefore, I believe if it is a one way itinerary, then you will be only changing that ONLY one segment.
 
Ranch Hand
Posts: 1183
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Jeremy and David,

It's interesting to note that this deleted segment can be replaced by an entire itinerary, as the Prepare Itinerary Use Case in executed.

-- Dan
 
Jeremy Hsu
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, Dan.

Thanks for this insight. However, I believe we can safely make the assumption that the search information will be automatically filled out by the change itinerary. As a result, only that segment will be preplaced and not by the entire itinerary.

This exam has a lot of questionable area and we have to make assumptions.
 
Ranch Hand
Posts: 208
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Suppose the flight path is A --> B --> C. A --> B has been replaced by A --> Z -->B, the new flight path is A --> Z --B --C. As long as there is no problemn with time departured from B --> C, I don't see any problem.
 
Dan Drillich
Ranch Hand
Posts: 1183
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I totally agree with Vu.
 
Greenhorn
Posts: 2
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Change Itinerary use case includes Prepare Itinerary use case. Change itinerary doesn't end until the included use case ends.(the two have same post conditions: a prepared Itinerary with identical words).

Regards
Alain
 
David Follow
Ranch Hand
Posts: 223
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

Originally posted by vu lee:
Suppose the flight path is A --> B --> C. A --> B has been replaced by A --> Z -->B, the new flight path is A --> Z --B --C. As long as there is no problemn with time departured from B --> C, I don't see any problem.



Hi Vu,

makes sense but what if the flight is A-->B-->C and the segment A-->B is replaced by the customer to X-->Y the itinerary would be X-->Y-->C but let's say there is no such thing as Y-->C ?!?
Should I make an assumption that such a case cannot occure since the underlying search algorithm (which is not part of the assigment) is smart enough to figure that out and only return possible combinations?

D.
[ July 11, 2005: Message edited by: David Follow ]
 
vu lee
Ranch Hand
Posts: 208
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
David,
The assignment states that a customer must select a segment to change. In your scenerio, it is not a segment;indeed, it is two segments A --> B and then B --> C.
If the customer selects A --> B segment, the destination city of the new itinerary must be B.
 
David Follow
Ranch Hand
Posts: 223
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

Originally posted by vu lee:
If the customer selects A --> B segment, the destination city of the new itinerary must be B.



Vu,

so is it correct to say that if the customer changes segment A-->B than he can change the departure city (A) but the destination city (B) must remain the same? Therefore he can change the segment A-->B to e.g. X-->B? So the itinerary becomes X-->B-->C?

D.
 
vu lee
Ranch Hand
Posts: 208
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
David,
That's right if an user picks the first segment. If the user pick the middle segment, two end points of that segment cannot be changed.
 
David Follow
Ranch Hand
Posts: 223
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Vu,

can I assume that the searching algorithm is taking care of that or do I actually have to come up with an algorithm that handles that? I guess it is beyond the scope of the assignment, what do you think? I guess providing an iterface for the search component (algorithm) should be enough, isn't it?

D.
 
vu lee
Ranch Hand
Posts: 208
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
You're right, David. Let's focus on the abstract design and take the 'design by contract' approach
 
David Follow
Ranch Hand
Posts: 223
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

Originally posted by vu lee:
You're right, David. Let's focus on the abstract design and take the 'design by contract' approach



Vu,

do you show this "Search" as a class in your class diagram, or will you depict it as a component in your component diagram?

D.
reply
    Bookmark Topic Watch Topic
  • New Topic