Graphical models with NModel

Jun 3, 2010 at 1:05 PM

A new NModel utility - GML.exe, will be included in a new release of NModel this summer (it is already in the source-code cs-50622).

The purpose of the GML utility is to enable the use of a graphical model editor (yED) and to enable the auto-generation of a C# model skeleton from yED’s exported graphml files.

In order for you to see how a graphical model looks like, I created a new document on the wiki and attached a picture of a model there (I couldn't find a way to attach a picture to a discussion):

Some of the benefits that can be achieved using the GML utility:

Non-technical product-managers:

  1. Can draw a model together with the requirements and visualize the behavior, while designing it.
  2. Can view some initial FSMs and scenarios for a first review of the specs design.

Technical product-managers:

  1. Can add code to the graphical models for advanced generated models. Using their coding skills (even basic skills) they can get more accurate models for a better review of their design.


  1. A generated c# skeleton of the model: all the main actions without code or with basic code, each action has its requirements attached, the main states, main constraints and the main accepting-states.
  2. Better understanding of the specs, visualization of the behavior flow and less ambiguous requirements (the graphical model is a partial formalization of the specs).

    3.   Accelerating the models’ development


Jun 4, 2010 at 3:48 AM


Thanks sir..So u mean to say using GML.exe, I can visually create the model (as an FSM or so) as u showed in the diagram and it will generate the c# model code and the test cases? It ll be great if u can explain more in detail sir..Also,please can u tel me from where I can download the GML.exe .Kindly help.Thanks in advance.

Jun 4, 2010 at 3:57 AM

Hi All,

Are there any other forums like this where discussions about model based testing are going on?If you have an idea or know what are the forums please post the names of those forums or discussion links.Thanks in advance.

Jun 6, 2010 at 7:13 AM

Sujithra, GML utility is now in the source code repository. It will be included in NModel's next official release (this summer).

I believe that developers can download the source code and build it, but as you know, the source code is less stable than an official release.


The graphical models that GML accepts currently are EFSM (Extended Finite State Machine) models.


I pasted the GML utility's README file (that is also in the source code repository) under the wiki's GML document ( where you can get more info for how to use it.


Other Model-Based-Testing forums: apart from forums like this one which you can find for other MBT tools as well, there are a few MBT general forums like this Yahoo group:, and a ModelBasedTesting group in LinkedIn.