Monthly Archives: January 2012

Getting Things Done

You may know an organizational method GTD (Getting Things Done). The idea is that the person moves tasks out of his mind into some external medium, exocortex. It may be a piece of paper or a text file or a database.

There are a lot of modifications of GTD. Some of them are quite sophisticated. They prescribe to classify tasks with many classifiers (project, activity, time, place, etc.) and to sort tasks a particular way.

I’ve tried some of these methods and some software products that support these methods. I can’t use each of them longer than 3 weeks, because they demand too much discipline.

But there is another edition of GTD that has proved to be useful. This method was described by Anatoly Levenchuk in this post (in Russian).

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UML Specification

Last year I posted UML class diagram that depicts core concepts of REA (resources, events, agents) data model. That’s it:


My colleague had looked at this diagram and said that it’s not canonical UML class diagram, because there is a generalization between associations.

I agree that it’s uncommon to show a generalization between associations in such diagrams. But it’s absolutely legal use of UML. Section 7.3.3 “Association (from Kernel)” of UML 2.0 spec describes semantics and notation of generalization between associations.

UML spec is huge (UML 2.0 superstructure specification has 710 pages), so it describes a plenty of definitions that are not in common use.