Prev: ANN: New Tool Automates Use Case and Sequence Diagram Generation
Next: Simple Adapter Pattern Question
From: frogoe on 26 Jul 2007 11:09
Hi,

Im pretty new at UML and was hoping for sm help in answering d
following questions, please :

1. IN ERD, i am able to show which fields in a table are PK, how do i
depict this unique field(s) for classes in a UML class diagram. For
example, all objects of the class Student will have a StudentID field
that is unique for every object. As far as i understand, this
uniqueness of objects is rightly a business requirement..no? am i
missing smtg here? If this unique field contraint is not kept in the
class diagram?

2. What are qualifiers used for?


any help would be greatly appreciated, i'm really stuck wit this.

thank u all :)

From: karl.wettin on 2 Aug 2007 06:13
On Jul 26, 5:09 pm, frogoe <ophelia...(a)yahoo.com> wrote:
> Hi,
>
> Im pretty new at UML and was hoping for sm help in answering d
> following questions, please :
>
> 1. IN ERD, i am able to show which fields in a table are PK, how do i
> depict this unique field(s) for classes in a UML class diagram. For
> example, all objects of the class Student will have a StudentID field
> that is unique for every object. As far as i understand, this
> uniqueness of objects is rightly a business requirement..no? am i
> missing smtg here? If this unique field contraint is not kept in the
> class diagram?

Primary keys, object identity et c has nothing to do with your class
diagram, it is something handled in the persistency layer and makes
just as much sense to note in a class diagram as stating what version
of HTML you use to draw the class GUI. Perhaps you use some attribute
such as email address, phone number or social security number as
object identity. I would then use a stereotype on the attribute to
show that.

There are many schools, and I'm sure there are people here with a
different opinon than I have. I come from MDA, thus I say keep you
platform independent model (PIM) independent. Don't go modelling the
platform dependent model (PDM). Rather use software or your head to
transform the PIM to a PDM.

> 2. What are qualifiers used for?

You might know them as maps.

[Bank](accountNumber)------- {0..1} -[BankAccount]

For each accountNumber in the bank, there is zero or one bank account.


I hope this helps.

--
karl

 | 
Pages: 1
Prev: ANN: New Tool Automates Use Case and Sequence Diagram Generation
Next: Simple Adapter Pattern Question