Feeds

Close the gap between analysis and design

Get robust

Gartner critical capabilities for enterprise endpoint backup

Robustness analysis in practice: take the test

As with our previous extracts, it's time for a quiz. This time, there's no top-10 list, but - instead - a visual puzzle. The robustness diagram excerpt (shown next) highlights a number of errors, including at least one in the use case text, in the last sentence of the basic course, and two where the text and the diagram don't match up. Have fun finding them all.

Figure 5-22. Excerpt from a robustness diagram with lots of errors

Spot the error - what's wrong with this diagram?

Did you spot the problems? Overall, the diagram doesn't match the description. Digging deeper, the first mistake is that the text starts at an earlier point in time than the diagram (a common mistake). An easy way to spot this type of error is to use the highlighter test.

The second error - the GUI widget is shown as a boundary object - is another common mistake. A GUI widget such as a button is too fine grained to be the boundary object; instead, the boundary object should be the screen or web page.

The third is fundamental: an entire chunk of the use-case text has been left off the diagram. It's surprising how often this happens. It's usually a sign that somebody isn't working through the use case one sentence at a time.

Our fourth and final problem is a direct consequence of ambiguous use case text. The text wasn't tied closely enough to the objects, so the modeler just sort of went off in a pseudo-random direction and, lacking the real boundary object to work with, used "Select address" as the boundary object, even though it's a verb and, therefore, is a controller masquerading as a boundary object. And as we're sure you know by now, actors can't talk directly to controllers.

Figure 5-28. The robustness diagram excerpt from Exercise 5-3, with errors highlighted

Seeing red - mistakes highlighted

In redrawing the diagram, shown next, we discovered another ambiguity in the text - funny how that happens!

The text "the system displays the Delivery Address page showing any addresses already registered for the user's account" implies some search and retrieval initialization behavior, which currently also doesn't appear anywhere on the diagram.

Secure remote control for conventional and virtual desktops

More from The Register

next story
Why has the web gone to hell? Market chaos and HUMAN NATURE
Tim Berners-Lee isn't happy, but we should be
Mozilla's 'Tiles' ads debut in new Firefox nightlies
You can try turning them off and on again
Microsoft boots 1,500 dodgy apps from the Windows Store
DEVELOPERS! DEVELOPERS! DEVELOPERS! Naughty, misleading developers!
'Stop dissing Google or quit': OK, I quit, says Code Club co-founder
And now a message from our sponsors: 'STFU or else'
Apple promises to lift Curse of the Drained iPhone 5 Battery
Have you tried turning it off and...? Never mind, here's a replacement
Uber, Lyft and cutting corners: The true face of the Sharing Economy
Casual labour and tired ideas = not really web-tastic
Linux turns 23 and Linus Torvalds celebrates as only he can
No, not with swearing, but by controlling the release cycle
prev story

Whitepapers

Gartner critical capabilities for enterprise endpoint backup
Learn why inSync received the highest overall rating from Druva and is the top choice for the mobile workforce.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Rethinking backup and recovery in the modern data center
Combining intelligence, operational analytics, and automation to enable efficient, data-driven IT organizations using the HP ABR approach.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.