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Updated: 3 hours 41 min ago

RE: [UML Forum] Understanding Relationships for Class Diagram

3 hours 41 min ago
Thanks Lahman, I got my answer... :)
Regards,
Sanjay Amin
Wipro Technologies
+91-20 30 96 02 07 (O) | +91-95 27 00 27 37 (M) | 8540207 (VOIP)
-----Original Message-----
Behalf Of H. S. Lahman
Sent: Wednesday, July 14, 2010 8:47 PM
To: umlforum@googlegroups.com
Responding to sanjay.amin...
And it was answered in my previous message. Evidently I was not clear
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AW: [UML Forum] Understanding Relationships for Class Diagram

3 hours 41 min ago
As mentioned, this depends on how your code is structured.

If you're creating a global attribute of Class B within Class A, this can be
achieved by an association. But an association doesn't indicate the calling
of an operation. Therefore, you must make use of a behavioral description in
the classifier behavior. Within classifier behavior you're able to describe

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Re: [UML Forum] Understanding Relationships for Class Diagram

3 hours 41 min ago
Responding to sanjay.amin...
And it was answered in my previous message. Evidently I was not clear
enough, so I will try again...
This *sounds* like composition; B is part of A's implementation and
therefore A control's B's disposition (life cycle). But, as I explained
in my previous message, it depends on the OOPL you are modeling (i.e.,
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RE: [UML Forum] Understanding Relationships for Class Diagram

3 hours 41 min ago
Thanks all for your inputs.

My question is very simple.

- I have a class named A
- I have a class named B
- I am creating an instance of class B inside class A
- I am calling a method of class B inside class A after
creating an instance of class B
- I am using an output of the operation of B in class A for

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Re: [UML Forum] Understanding Relationships for Class Diagram

3 hours 41 min ago
Hi Sanjay
For myself if I would usually expect a Java instance variable that refers to
some classes to be an association of some type (providing that class isn't
just a data type).
With your example though you have an instance variable that isn't actually
being used by any method. It such it serves no purpose as object state so I
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RE: [UML Forum] Understanding Relationships for Class Diagram

3 hours 41 min ago
Sanjay,

There are some problems with your example. Create it, compile it, and see
if it works.

I think the point you are asking is whether A is Dependent upon B's name.
Am I correct?
"A dependency is a relationship that signifies that a single or a set of
model elements requires other model elements for their specification or

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AW: [UML Forum] Understanding Relationships for Class Diagram

3 hours 41 min ago
Responding to Sanjay.

Your snippet represents neither an association nor a dependency. As I
mentioned in my previous mail, a dependency is more or less a meta-concept,
indicating that a class is using another class. For my understanding a
dependency would result in the javadoc of class A.

Look to a similar snippet of your's:

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Re: [UML Forum] Understanding Relationships for Class Diagram

3 hours 41 min ago
Responding to sanjay.amin...
It is confusing because they model different things so they can overlap
for the same classes. The first four describe relationships between
n-ary relations in relational theory. Dependency describes physical
coupling at the 3GL level. That is, dependency describes what one object
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[UML Forum] Understanding Relationships for Class Diagram

3 hours 41 min ago
Hi Ken,

I know about the relationships categorized as following.

* association
* aggregation
* composition
* generalization
* dependency

What I want to know is precise definitions of each and when to use that
kind of relationship (scenario). I read some UML documents, but still
not clear about when to use dependency and when to use association.

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RE: [UML Forum] Primitive Type musn't be a DataType

3 hours 41 min ago
Sanjay,

There are many Relationships (graph edges) in the UML. Associations and
Dependencies are just two. Compare Associations between classes with Links
between Objects.

The two representations of ClassA, below (or attached), are almost identical
(assuming b::ClassB in the top representation MUST exist). This Association

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RE: [UML Forum] Primitive Type musn't be a DataType

3 hours 41 min ago
All,

The original edition "The Unified Modeling Language Reference Manual" by
Rumbaugh, Jacobson and Booch (Addison-Wesley) is available online at:

[link]
ge%20Reference%20Manual.pdf

Note: This details UML 1.x. It illustrates many excellent concepts, but not

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Re: [UML Forum] Primitive Type musn't be a DataType

3 hours 41 min ago
Hi Ken Lloyd,
Can you please help me I want to learn UML from scratch.
How to design class diagram ,object diagram in UML.
Can you please suggest any source over internet from where i can learn UML
language othet than from basic
other than
[link]
[link]
Thanks
Vinay
Please help me then I would be thankful to you
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AW: [UML Forum] Primitive Type musn't be a DataType

3 hours 41 min ago
Responding to Sanjay.

It depends on what do you want to express. Dependencies can be used to say,
that class A uses class B somehow, this indicates the usage of class B's
methods as well. It is a kind of meta-concept, saying that there is a
logical relationship between both classes. By using an association, you

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RE: [UML Forum] Primitive Type musn't be a DataType

3 hours 41 min ago
Hi Ken,

Thanks a lot for the information. The links are pretty useful.

I am using Java. I have a java class and I am calling other java class
by creating an instance and calling some of its method. Is this
indicates dependency or association? Where can I find few examples
related to class diagrams and relationships?

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RE: [UML Forum] Primitive Type musn't be a DataType

3 hours 41 min ago
Hi Sanjay,

Assuming you already really know programming (Java and c++), to understand
the classes and diagrams defined in the UML, read the Infrastructure and
Superstructure specifications available from OMG. This shows how the
modeling language is "built up" from first principles.
[link]

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Re: [UML Forum] Difference between InstanceSpecification and LiteralSpecification

Wed, 07/14/2010 - 05:42
Responding to Marc...
This mechanism is the one sued to describe ADTs (see my response to your
other message) when they are complex data structures with discrete,
different, identifiable members. Thus an ADT of ComplexNumber actually
represents a data structure of {real, imaginary} where 'real' and
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Re: [UML Forum] Primitive Type musn't be a DataType

Wed, 07/14/2010 - 05:42
Responding to Marc...
What OMG is trying to describe is what everyone else calls and Abstract
Data Type (ADT). That is, a data structure that can be hidden behind a
scalar knowledge attribute. Thus the details of the data
implementation's complexity are not of interest at the level of
abstraction of the containing subsystem so they are hidden. The use of
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RE: [UML Forum] Primitive Type musn't be a DataType

Wed, 07/14/2010 - 05:42
Hi,
Can anyone provide a tutorial that explains the classes and diagrams
step by step?

Regards,
Sanjay Amin

Behalf Of Timothy Marc
Sent: Friday, July 09, 2010 1:40 PM
To: umlforum@googlegroups.com

Hi again,

another question regarding PrimitiveTypes. With respect to the UML2
spec, PrimitiveTypes may not have any logical structure. That means,

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[UML Forum] Primitive Type musn't be a DataType

Wed, 07/14/2010 - 05:42
Hi again,

another question regarding PrimitiveTypes. With respect to the UML2 spec,
PrimitiveTypes may not have any logical structure. That means, they won't
have operations and attributes within UML (the spec mentiones clearly that
operations and structures may be defined outside of the scope of UML). But

Categories: Communities

[UML Forum] Difference between InstanceSpecification and LiteralSpecification

Tue, 07/13/2010 - 05:29
Hi all,

i have a question regarding the instantiation of primitive types in UML2.
The spec itself provides two different mechanisms for it and I would like to
ensure whether there are semantically equivalent or different.

On the one hand, there is the metaclass InstanceSpecification. It may point

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