Tag: viatra

Source code visualisation for my projects

Today I read the announcement of SourceCloud, a new Zest/Cloudio-based visualization for source code. As I like cool visualizations, I tried it out on the open projects I am participating in.At first I created the cloud for the source code of the Debug Visualisation project. Globally it consists of about half Eclipse debugger/UI and Java keywords – as this is quite a small project (about 4 kLOC), this is somewhat expected with 200 words.

SourceCloud of the Debug Visualisation Project

However, it is interesting, that the strings ‘end_of_line‘ and ‘sp_cleanup‘ found their way in. Luckily, only a few one-character names and numbers are present, meaning, we managed to created longer variable names…

The cloud of the VIATRA2 model transformation framework is more interesting: it is a much larger codebase, developed for several year by around a dozen people. Because of the size I generated the cloud using 300 words, but almost no Java keywords found their way into the graph.

SourceCloud of the VIATRA2 framework

However, the mandatory comment parts did, e.g. nbsp or the names of some creators. A lot of EMF-specific keywords are also present. They are present because we have quite a large EMF metamodel that provides several hundred generated Java files.

At last, but not least I also checked the cloud of the EMF-IncQuery project. This is smaller, then the VIATRA2 project, but larger then the Debug Visualisation. Additionally, it has a shorter history, but with several key committers.

SourceCloud of the EMF-IncQuery project

My personal favorite is this diagram, as it shows a lot of nice things: e.g. four digit numbers in large quantities (magic numbers FTW) or the absolute champion string: ‘HUKfyM7ahfg‘. All of them are present in the Ecore Diagram of the defined metamodel (the meaningless string 152 times as a postfix of an identifier 🙂 ). At least, I learned something about the internal model representation of GMF.

And how do your projects look like?

Incremental validation of UML models using EMF-IncQuery

Last week we created in the university a nice demo application to demonstrate the validation capabilities of our EMF-IncQuery framework. The application was presented on the conference ECMFA 2011 as a tutorial.

EMF-IncQuery provides an incrementally evaluated model query framework: as the underlying EMF model is changed, the query results are re-evaluated, and are instantly returned when needed. Queries are formulated using the pattern language of the VIATRA2 transformation system, and the Java code necessary to execute queries are generated.

In our demo application we extended the Papyrus UML editor with on-the-fly validation of well-formedness constraints. During editing we check for non-local constraints (e.g. a Behaviour must have the same number of parameters as the corresponding operation); display the results in the editor and in the problems view; we try to provide and remove these error markers without saving or manual need to start validation.

Basically, the constraint validators are generated from specially annotated VIATRA2 patterns; the generation is currently somewhat specific to the Papyrus editor, but can be extended to support most EMF-based editors easily.

A screencast of the demo is presented below. It is important to note, that the Papyrus editor was not modified in any way, and the framework generated all Java code used during validation. More details about the demo application, such as source code, tutorial slides, can be found on the homepage of the application.

(If the embedded video does not show – e.g. in a feed reader – you could watch it on on Youtube)