I sat down for a while and extended the Grails Create Domain UML Plugin that I wrote about a couple month ago in this post. This plugin helps to generate UML class diagrams with yUML from a Grails domain model. Unfortunately the diagrams don’t show aggregations or compositions and the associations don’t have a name. I fixed that, but the generated diagrams are not really useable, because yUML is only for very simple UML class diagrams as you can see in the following pictures.

Neat top down

Neat left right

Conclusion: yUML looks nice, but is only usable for very simple diagrams.