CodEagle

Recently I had an interesting discussion on the DDD mailing list about value objects.

Value objects: “These are the objects that describe things” [From: DDD, Evans]

The discussion centered on the immutability of value objects. The strange thing is that many developers (in the role a modeller) emphasize this immutability. I’ve seen this happen quite often. While I do not think that is the essence of a value object at all. read more…

In response to a finding during an internal project code review last Friday and an article in the latest Java Magazine we had an interesting discussion on the reasons for using exceptions. Eventually I supported two rules of thumb, one I had thought of myself, the other from a colleague of mine.

The following rules of thumb should be seen as in the context of a development platform that supports their use and a developer who uses as the following, basic rule for recognizing the situation to use an exception: use an exception if you cannot follow the normal execution path any more, in other words, if something extraordinary happens or has happened. read more…

Last wednesday there was another Devnology event: the developers of the round table met at.. a rectangular one. Despite the out-of-place table, it was a very good meeting in any way that matters. I couldn’t shake of the feeling that the program didn’t fully work out as planned, but everybody was completely cool with it and the result was even better than planned. Discussions! And lots of it, of pretty high quality. See for yourself, as a picture says more than a thousand words..

After the event, Pieter-Joost van der Sande and I had a nice little off-time discussion about the interchangeability of Test-Driven Development and Design by Contract. PJ, correct me if I am wrong, but I remember you defending the viewpoint that DbC is an improvement over unit tests and consequently over TDD too. DbC is all a developer needs. Might be a bit of an exaggeration, but it comes close to what you said, right? read more…