Component DIagram question

[Bijan Mohanty]

Hi folks,
Do you guys create a component diagram for each use case defined in the assignment ? I am wondering on what basis do you break down the component diagram ? Is it on use case or logically ? Also, do you include all your WAF components in all your component diagrams or just create one component diagram for WAF components only and refer from all your diagrams.
Thanks a lot.
Bijan
[ August 18, 2003: Message edited by: Bijan Mohanty ]

[Ajith Kallambella]

Since component diagrams show *all* applications components, there should be only one component diagram. You should include Web tier components, enterprise components(ejbs) and anything else that make up your application.

[Bijan Mohanty]

Hi Ajith,
Thanks for the reply. But, if you make just one component diagram, don't you think, putting all your components(JSP, Servlet, BusinessDeligates, EJBs, subsystems) will make the diagram pretty big and unmanageble ?
Thanks.
Bijan

[Ajith Kallambella]

It will certainly make it pretty big, no doubt about it. But it is typical to have one component diagram per system. Frankly I have not seen multiple component diagrams and definitely not one per use case.
May be creating multiple component diagrams- one for the web tier, one for the enterprise tier etc, makes sense, but doesn't the assignment guidelines specifically say only one each of class diagram and component diagram is required? You may be risking non-compliance by submitting multiple component diagrams.....

[Nalla Senthilnathan]

Originally posted by Bijan Mohanty:
Hi Ajith,
Thanks for the reply. But, if you make just one component diagram, don't you think, putting all your components(JSP, Servlet, BusinessDeligates, EJBs, subsystems) will make the diagram pretty big and unmanageble ?
Thanks.
Bijan

Hi Bijan,
I think The BluePrints book ( http://java.sun.com/blueprints/guidelines/designing_enterprise_applications_2e/app-arch/app-arch5.html ) provides some hints to this question:
1. make one component diagram showing all subsystems (Figure 11.4)
2. make one component diagram per subsystem (Figure 11.6, Figure 11.10)
Note that the above diagrams do not explicitly display J2EE components (like EJB, XML file, JSP etc) but rather "modules" that encapsulate one or more J2EE components. So one could show the content of each "module" in the diagram as a text note. In fact, the book lists all the J2EE components (EJBs, JSPs etc) at end. (see page 51 in http://java.sun.com/blueprints/guidelines/designing_enterprise_applications_2e/sample-app/sample-app1.3.1.pdf
Hope that helps,
Nalla
[ August 19, 2003: Message edited by: Nalla Senthilnathan ]
[ August 19, 2003: Message edited by: Nalla Senthilnathan ]
[ August 19, 2003: Message edited by: Nalla Senthilnathan ]

[Bijan Mohanty]

Hi Ajith/Nalla,
Thanks a lot for your inputs. I'll keep only one component diagram then. I have one last question on this topic. I am using the same kind of WAF that Petstore uses. So in this case I need to show the RequestProcessor, ScreenFlowManager(They will be just one component) and the Action classes(will be many for my domain) and the Event classes(Again many classes for my domain). I am wondering if it's necessary to show all the Action classes and Events for my domain or just showing one component as "WebAction" and one component as "EJBAction" will be sufficient ?
What you guys have done if you have used this WAF ? If you have used Structs, do you show all your domain action classes or just one component as the strutAction ?
I hope I am not confusing you guys.
Thanks.
Bijan

[Billy Tsai]

did you draw a deployment diagram with all the components inside the nodes?

[Rufus BugleWeed]

It will certainly make it pretty big, no doubt about it.

How many components did you have on your drawing submitted for part II?

[Rufus BugleWeed]

Frankly I have not seen multiple component diagrams...

There's three in Sun Certified Enterprise Architect for J2EE Technology Study Guide, Sun Microsystems Press, publisher.

You may be risking non-compliance by submitting multiple component diagrams.....

No, you do not. Jitender Bhatia submitted 4 and scored 100%.
An architect must be a leader. An architect should strive to create a design that's easy to understand. If four component diagrams conveys your design more clearly, then draw four. One big diagram with horizontal - vertical scrolling and 125 components is going to be a roadblock unless you can print it out and hang it on the wall.