Thursday, June 11, 2009

Slides from JavaOne BOF on the SCEA exam

I've posted the slides for my BOF talk at JavaOne - enjoy! (including the obvious typo on slide 16).

3 comments:

Anonymous said...

Hi,

Your general purpose for all diagrams states that a 1280 x 800 resolution browser window should not need scrollbars.

My assignment has 49 class, 21 interfaces and 21 EJBs. I don't see how you can designed solution that addresses all the requirements and still cram the class diagram into that amount of space.

Many of the certification guide books show extremely over simplified diagrams. However, an often unavoidable side of good object-oriented design is that you tend to get a large number of classes.

Support internationalisation or implement the state pattern a couple of times and, bang, the number of classes and/or interfaces goes way beyond what you can fit on a single screen.

You also state that splitting the class diagram up should be avoided. If you have a large number of classes and section of the diagram are not coupled would you not advocate splitting for manageability and readability?

Anonymous said...

Hi,

Your general purpose for all diagrams states that a 1280 x 800 resolution browser window should not need scrollbars.

My assignment has 49 class, 21 interfaces and 21 EJBs. I don't see how you can designed solution that addresses all the requirements and still cram the class diagram into that amount of space.

Many of the certification guide books show extremely over simplified diagrams. However, an often unavoidable side of good object-oriented design is that you tend to get a large number of classes.

Support internationalisation or implement the state pattern a couple of times and, bang, the number of classes and/or interfaces goes way beyond what you can fit on a single screen.

You also state that splitting the class diagram up should be avoided. If you have a large number of classes and section of the diagram are not coupled would you not advocate splitting for manageability and readability?

Humphrey Sheil said...

Hi

RE: screen resolution, I take your point. A fairer request would be to ask that the class diagram fit into a screen res of 1680 x 1050 for a 21 inch monitor.

RE: fragmenting the class diagram, I genuinely advocate against this and do so quite strongly. Fragmentation by itself is not the issue, but almost all candidates who do fragment, never provide a joined-up view clearly showing that their multiple class diagram fragments fulfil the business problem laid out in the domain model. Specifically, they lose many marks because association and multiplicity information between entities.

Finally, I believe that the complexity of the assignments in the exam don't require fragmentation.

Humphrey