Information Technology Reference
In-Depth Information
One area where there has recently been a step forward in this respect is the
development of model-driven engineering solutions, in which transformational
techniques are applied to a quite abstract design, filling in detail to generate
code suited to a particular environment. This process is generally not com-
pletely automatable, but reports based on test cases show that up to 85%
automatic generation can be achieved in a typical database application [56].
OMG maintains an interesting library of such case studies [38].
This kind of integration is essential for the effective exploitation of a multi-
viewpoint framework. Information needs to be taken from each viewpoint
and combined to create a running system. As the design evolves, there need
to be simple ways of checking that its parts have at least a basic level of
consistency (just as compilation of a multi-package program gives some check
on its structural coherence). All this requires the tools used in the different
viewpoints to interwork so that checks can be made to see that the rules in
the different viewpoints do not lead to contradictions.
Model-driven tools offer not only a much smoother pathway from design
to implementation, but also a much more ecient basis for the management
and evolution of large systems.
Marcus was sitting in on the design review to support Alex. Although the
consultant was now known to the team and largely accepted, there had been
teething troubles and a few bruised egos, so that support was still needed.
Marcus had to admit he didn't follow a lot of the detail, but he could see that
the main features of the new PhoneMob system were coming together.
It always intrigued him to see how the different groups imposed their own
style on their models. He could recognize the organic style of the data mod-
ellers, with the branches and leaves growing and unfolding across the page,
and could distinguish it from the Norman crypt style of the platform people,
with whole solid blocks of function stacked up into stocky columns leading
up to a broad vault of interconnections. The applications designers favoured
tight modular balloons, kissing to exchange their messages. And the business
analysts, with their narrow striped shirts, favoured road maps with the main
routes and the special byways picked out with graphical symbols for all the
world like service stations and tourist attractions.
But, putting aside these speculations, he knew it was not all going
smoothly. There were rough edges and there were disputes. Even Marcus
could see from the presentations that some things were being repeated by the
different groups, but each in their own way. This needed to be sorted out.
\Look," said Alex, \there is excellent work here, but you need to move
towards seeing what you are doing as part of a bigger whole, and exploit it to
simplify your lives." He turned to Claire. \Here, in the initial client registra-
tion, you have a big set of classes dealing with identity, account and contact
details.
And here, in the billing step, you have a different presentation of
