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Object diagram for a simple class diagram [message #472660]

Thu, 19 April 2007 08:14

Steffen Mazanek

Messages: 40
Registered: July 2009

Member

Hello,

to understand how the EMF UML model works I would
really like to see the mapping of a simple class
diagram to its internal representation.

For example, say we have class A, class B and B
extends A. How would the corresponding object diagram
look like? How are the EClasses Class and Generalization
arranged and instances of which additional classes are
needed?

Do you know any resources that demonstrate this "by example"?

Best regards,

Steffen

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Re: Object diagram for a simple class diagram [message #472667 is a reply to message #472660]

Thu, 19 April 2007 13:19

james bruck

Messages: 1724
Registered: July 2009

Senior Member

Hi Steffen,

some comments below ...

- James.

"Steffen Mazanek" <modeling@steffen-mazanek.de> wrote in message
news:f078bb$ts3$1@build.eclipse.org...
> Hello,
>
> to understand how the EMF UML model works I would
> really like to see the mapping of a simple class
> diagram to its internal representation.

I think you want are asking for is the UML model for a given class diagram.
You can have a look at the UMLTools project to create a class diagram and
then have a look at the .uml model that results.
If you want to see the EMF representation you can use the menu option to
"Convert to Ecore.." from the UML menu.

>
> For example, say we have class A, class B and B
> extends A. How would the corresponding object diagram
> look like?

Do you want the Object diagram or Class diagram? Object diagrams in UML
are for showing instances of the classes. I think you mean Class diagram?
EMF does not concern itself with InstanceSpecifications.

>How are the EClasses Class and Generalization
> arranged and instances of which additional classes are
> needed?

EClass is not part of the UML metamodel, it is part of the ecore metamodel.
You would see instances of Class and Generalization in your UML model.
Basically, EMF only concerns itself with the class diagram portion of UML.

>
> Do you know any resources that demonstrate this "by example"?

Have a look at the EMF site.. I believe they have some articles which show a
UML class diagram and ecore representation, or you can experiment with a
tool that allows you to draw UML diagram to produce a UML model, then
convert that model to its ecore representation. The UMLTools project is
another place to look.

>
>
> Best regards,
>
> Steffen

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Re: Object diagram for a simple class diagram [message #472687 is a reply to message #472667]

Fri, 20 April 2007 05:19

Steffen Mazanek

Messages: 40
Registered: July 2009

Member

Hello James,

thank you for your support.

>> to understand how the EMF UML model works I would
>> really like to see the mapping of a simple class
>> diagram to its internal representation.
>
> I think you want are asking for is the UML model for a given class diagram.
> You can have a look at the UMLTools project to create a class diagram and
> then have a look at the .uml model that results.
> If you want to see the EMF representation you can use the menu option to
> "Convert to Ecore.." from the UML menu.

I would like to see how a concrete uml class diagram is represented. For
example, a class A is an instance of EMF class Class, an association is
an instance of EMF class Association and so on. I do not want to see an
example object diagram for my class diagram, i.e. a:A and b:B ...

Thank you for pointing me to the .uml model - this sounds promising to me.

Best regards,

Steffen

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Re: Object diagram for a simple class diagram [message #472691 is a reply to message #472667]

Fri, 20 April 2007 06:23

Steffen Mazanek

Messages: 40
Registered: July 2009

Member

I did as you suggested and the following link was very helpful for me:

http://dev.eclipse.org/viewcvs/indextools.cgi/uml2-home/docs /articles/Getting_Started_with_UML2/article.html

However there is one thing I still not understand. Assume we have a
Customer and a Supplier class and a m:n association BusinessRelationship.
Why do we need an instance of "Owned Member Association" with two
properties customers and suppliers and in addition we need two "Owned
Attribute Properties" as elements of the classes Customer and Supplier
(redundantly). How are these properties "unified"? In the resulting
xmi-file the ids seem to be different. Or have I made a mistake?

And finally: do the xmi:type attributes in the xmi-file contain the
names of the EMF classes? (I was a little bit confused how to get these
names given only the names in the dropdown list of the example uml editor).

Best regards,

Steffen

James Bruck schrieb:
> Hi Steffen,
>
> some comments below ...
>
> - James.
>
> "Steffen Mazanek" <modeling@steffen-mazanek.de> wrote in message
> news:f078bb$ts3$1@build.eclipse.org...
>> Hello,
>>
>> to understand how the EMF UML model works I would
>> really like to see the mapping of a simple class
>> diagram to its internal representation.
>
> I think you want are asking for is the UML model for a given class diagram.
> You can have a look at the UMLTools project to create a class diagram and
> then have a look at the .uml model that results.
> If you want to see the EMF representation you can use the menu option to
> "Convert to Ecore.." from the UML menu.
>
>> For example, say we have class A, class B and B
>> extends A. How would the corresponding object diagram
>> look like?
>
> Do you want the Object diagram or Class diagram? Object diagrams in UML
> are for showing instances of the classes. I think you mean Class diagram?
> EMF does not concern itself with InstanceSpecifications.
>
>> How are the EClasses Class and Generalization
>> arranged and instances of which additional classes are
>> needed?
>
> EClass is not part of the UML metamodel, it is part of the ecore metamodel.
> You would see instances of Class and Generalization in your UML model.
> Basically, EMF only concerns itself with the class diagram portion of UML.
>
>> Do you know any resources that demonstrate this "by example"?
>
> Have a look at the EMF site.. I believe they have some articles which show a
> UML class diagram and ecore representation, or you can experiment with a
> tool that allows you to draw UML diagram to produce a UML model, then
> convert that model to its ecore representation. The UMLTools project is
> another place to look.
>
>>
>> Best regards,
>>
>> Steffen
>
>

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Re: Object diagram for a simple class diagram [message #472710 is a reply to message #472691]

Fri, 20 April 2007 15:32

james bruck

Messages: 1724
Registered: July 2009

Senior Member

Hi Steffen,

Some comments below ...

- James.

"Steffen Mazanek" <modeling@steffen-mazanek.de> wrote in message
news:f09m75$9lp$1@build.eclipse.org...
> I did as you suggested and the following link was very helpful for me:
>
>
http://dev.eclipse.org/viewcvs/indextools.cgi/uml2-home/docs /articles/Getting_Started_with_UML2/article.html
>
> However there is one thing I still not understand. Assume we have a
> Customer and a Supplier class and a m:n association BusinessRelationship.
> Why do we need an instance of "Owned Member Association" with two
> properties customers and suppliers and in addition we need two "Owned
> Attribute Properties" as elements of the classes Customer and Supplier
> (redundantly).

I think what you are seeing is that Customer and Supplier are owned members
of the model "epo2".
Supplier has a property "customers" of type Customer etc.

I had a quick look at the xml for that model I cannot find the association
with two properties as you mentioned.
Could you possibly be seeing the association with memberEnds being
serialized? That would make more sense.
Please copy the .xml to point out exactly what you are seeing.

You should not be seeing duplicate properties, one under the class and one
under the association.

>How are these properties "unified"? In the resulting
> xmi-file the ids seem to be different. Or have I made a mistake?
>
> And finally: do the xmi:type attributes in the xmi-file contain the
> names of the EMF classes? (I was a little bit confused how to get these
> names given only the names in the dropdown list of the example uml
editor).

Resulting EMF EClass would get their names from the name of the UML Class.
The UMLtoEcore converter in UMLUtil does this.

>
> Best regards,
>
> Steffen
>
> James Bruck schrieb:
> > Hi Steffen,
> >
> > some comments below ...
> >
> > - James.
> >
> > "Steffen Mazanek" <modeling@steffen-mazanek.de> wrote in message
> > news:f078bb$ts3$1@build.eclipse.org...
> >> Hello,
> >>
> >> to understand how the EMF UML model works I would
> >> really like to see the mapping of a simple class
> >> diagram to its internal representation.
> >
> > I think you want are asking for is the UML model for a given class
diagram.
> > You can have a look at the UMLTools project to create a class diagram
and
> > then have a look at the .uml model that results.
> > If you want to see the EMF representation you can use the menu option to
> > "Convert to Ecore.." from the UML menu.
> >
> >> For example, say we have class A, class B and B
> >> extends A. How would the corresponding object diagram
> >> look like?
> >
> > Do you want the Object diagram or Class diagram? Object diagrams in
UML
> > are for showing instances of the classes. I think you mean Class
diagram?
> > EMF does not concern itself with InstanceSpecifications.
> >
> >> How are the EClasses Class and Generalization
> >> arranged and instances of which additional classes are
> >> needed?
> >
> > EClass is not part of the UML metamodel, it is part of the ecore
metamodel.
> > You would see instances of Class and Generalization in your UML model.
> > Basically, EMF only concerns itself with the class diagram portion of
UML.
> >
> >> Do you know any resources that demonstrate this "by example"?
> >
> > Have a look at the EMF site.. I believe they have some articles which
show a
> > UML class diagram and ecore representation, or you can experiment with a
> > tool that allows you to draw UML diagram to produce a UML model, then
> > convert that model to its ecore representation. The UMLTools project is
> > another place to look.
> >
> >>
> >> Best regards,
> >>
> >> Steffen
> >
> >

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Re: Object diagram for a simple class diagram [message #472735 is a reply to message #472710]

Mon, 23 April 2007 18:14

Steffen Mazanek

Messages: 40
Registered: July 2009

Member

Hello James,

thank you a very lot for helping me.

I have problems understanding what you say. So I read through a bunch of
documentation by this time. Hopefully I can formulate my problem more
precisely thereafter.

I try to generate a standard uml-editor (tree-editor) and use this
instead of the customized one, because I hope to get a better insight
into the relations between the classes representing the uml metamodel.

Best regards,
Steffen

>
> I think what you are seeing is that Customer and Supplier are owned members
> of the model "epo2".
> Supplier has a property "customers" of type Customer etc.
>
> I had a quick look at the xml for that model I cannot find the association
> with two properties as you mentioned.
> Could you possibly be seeing the association with memberEnds being
> serialized? That would make more sense.
> Please copy the .xml to point out exactly what you are seeing.
>
> You should not be seeing duplicate properties, one under the class and one
> under the association.
>
>
>> How are these properties "unified"? In the resulting
>> xmi-file the ids seem to be different. Or have I made a mistake?
>>
>> And finally: do the xmi:type attributes in the xmi-file contain the
>> names of the EMF classes? (I was a little bit confused how to get these
>> names given only the names in the dropdown list of the example uml
> editor).
>
> Resulting EMF EClass would get their names from the name of the UML Class.
> The UMLtoEcore converter in UMLUtil does this.
>
>> Best regards,
>>
>> Steffen
>>
>> James Bruck schrieb:
>>> Hi Steffen,
>>>
>>> some comments below ...
>>>
>>> - James.
>>>
>>> "Steffen Mazanek" <modeling@steffen-mazanek.de> wrote in message
>>> news:f078bb$ts3$1@build.eclipse.org...
>>>> Hello,
>>>>
>>>> to understand how the EMF UML model works I would
>>>> really like to see the mapping of a simple class
>>>> diagram to its internal representation.
>>> I think you want are asking for is the UML model for a given class
> diagram.
>>> You can have a look at the UMLTools project to create a class diagram
> and
>>> then have a look at the .uml model that results.
>>> If you want to see the EMF representation you can use the menu option to
>>> "Convert to Ecore.." from the UML menu.
>>>
>>>> For example, say we have class A, class B and B
>>>> extends A. How would the corresponding object diagram
>>>> look like?
>>> Do you want the Object diagram or Class diagram? Object diagrams in
> UML
>>> are for showing instances of the classes. I think you mean Class
> diagram?
>>> EMF does not concern itself with InstanceSpecifications.
>>>
>>>> How are the EClasses Class and Generalization
>>>> arranged and instances of which additional classes are
>>>> needed?
>>> EClass is not part of the UML metamodel, it is part of the ecore
> metamodel.
>>> You would see instances of Class and Generalization in your UML model.
>>> Basically, EMF only concerns itself with the class diagram portion of
> UML.
>>>> Do you know any resources that demonstrate this "by example"?
>>> Have a look at the EMF site.. I believe they have some articles which
> show a
>>> UML class diagram and ecore representation, or you can experiment with a
>>> tool that allows you to draw UML diagram to produce a UML model, then
>>> convert that model to its ecore representation. The UMLTools project is
>>> another place to look.
>>>
>>>> Best regards,
>>>>
>>>> Steffen
>>>
>
>

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