Feeds

Why UML won't save your project

Modelling a badly thought-out project just doesn't help...

Security for virtualized datacentres

The project's been wobbling along for 18 months. A bottle of champagne just went to the tester who logged the one millionth bug in TestDirector (and everybody cheered), the lead programmer looks like a raccoon that's discovered a departed junkie's heroin stash buried beneath a tree, half the programmers have quit, and the customer believes everything's fine... Although it does strike him as odd that all he's seen so far are static screenshots and Gantt charts with every single task stuck at "90 per cent". The project's in trouble.

head shot of Matt Stephens smilingSo what does the team do? They've read the IBM/Rational marketing blurb, so they firmly believe that they can "do UML" on their project and that this'll have a miraculous effect on the bug-riddled codebase. It's this vague desire to start doing the right thing in order to save the project that can sink a team even further into the swamp.

When a project is in trouble because of a lack of initial analysis/design thought, the worst thing to do is to stop everything and start modelling the whole sorry mess in a CASE tool. It seems reasonable to want to create a clear picture of where you're at: a level playing field from which to start fixing the design. But muddy water poured into a crystal flute is still muddy water. Now you've got the same dysfunctional mudball in two places - the code and the UML model. Great.

It's also tempting to automatically reverse-engineer the code into class diagrams using a modelling tool. This might have an unseen benefit in that it'll shock whoever sees the resultant diagrams into realising just how bad the problem has gotten, but the diagrams themselves will be as scary as the code they're modelled on, a jumble of criss-crossed lines and teeny-tiny overlapping boxes that could rival anything in the Tate Modern.

I'm a great fan of UML, but like any tool or language it can be misused horribly – and usually is, because people start to use it for the wrong reasons, e.g. to do the thinking for them or make their team cleverer.

The right time for drawing diagrams is near the start of the project (or new feature, or weekly/monthly development sprint) when you do a little collaborative modelling with the whole team involved and figure out how it'll all fit together.

So it's worth emphasising: the solution is not to start modelling the existing illogical codebase in UML. However, do map out your ideal new improved design, unfettered by the constraints and design dead-ends of the current system. But the first thing to do (assuming you can't just scrap it all and start over) is cover the existing code with unit tests so you can begin refactoring your way to the new design.

But even before that, you must know what it is you're actually designing. Start with the basic questions: Who's the project for? What problems is it addressing? If you're feeling especially virtuous today, map out some use cases and try to drive the new design from them. Don't be afraid to come up with something very different from what you currently have.

UML used at the right time and in the right way can work wonders - it'll set the foundations for a successful, well factored project. But, to adapt Frederick Brooks' famous law about the perils of adding resources to a late project, stopping to map out the bad design on a late project will just make the project later.

Matt Stephens co-authored Use Case Driven Object Modeling with UML: Theory and Practice and Agile Development with the ICONIX Process.

Secure remote control for conventional and virtual desktops

More from The Register

next story
Microsoft to bake Skype into IE, without plugins
Redmond thinks the Object Real-Time Communications API for WebRTC is ready to roll
Microsoft promises Windows 10 will mean two-factor auth for all
Sneak peek at security features Redmond's baking into new OS
Mozilla: Spidermonkey ATE Apple's JavaScriptCore, THRASHED Google V8
Moz man claims the win on rivals' own benchmarks
FTDI yanks chip-bricking driver from Windows Update, vows to fight on
Next driver to battle fake chips with 'non-invasive' methods
PEAK APPLE: iOS 8 is least popular Cupertino mobile OS in all of HUMAN HISTORY
'Nerd release' finally staggers past 50 per cent adoption
DEATH by PowerPoint: Microsoft warns of 0-day attack hidden in slides
Might put out patch in update, might chuck it out sooner
Ubuntu 14.10 tries pulling a Steve Ballmer on cloudy offerings
Oi, Windows, centOS and openSUSE – behave, we're all friends here
Was ist das? Eine neue Suse Linux Enterprise? Ausgezeichnet!
Version 12 first major-number Suse release since 2009
prev story

Whitepapers

Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.
The hidden costs of self-signed SSL certificates
Exploring the true TCO for self-signed SSL certificates, including a side-by-side comparison of a self-signed architecture versus working with a third-party SSL vendor.