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AIST > RISEC > Projects > Modbat: A model-based tester

Modbat: A model-based tester


Modbat is a model-based testing tool that is based on annotated (extended) finite-state machines. Modbat is specialized to testing the application programming interface (API) of software. The model used by Modbat is compatible with Java bytecode. The user defines and compiles a model, which is then explored by Modbat and executed against the system under test. Failed test runs are reported as an error trace.


  • Easy-to-learn modeling language with graphical view of model.
  • Efficient test generation and execution.
  • Offline test case generation and other advanced features.

How it works

Modbat is based on Scala and compatible with any Java-based software. The model has the structure of a non-deterministic finite-state machine. From all possible transitions, one is chosen to be tested; annotations of the transition specify which code to execute.

[Extended finite-state machine]
Extended finite-state machine

Modbat is currently under active development. The first version is available on a trial basis; it can be obtained without registration. Modbat version 1.0.2 is free to use, but the software may not be modified, reverse engineered, or released to third parties.


  • Cyrille Artho
  • Armin Biere (Institute for Formal Models and Verification, Johannes Kepler University in Linz, Austria)


Modbat home page