AspModificator is an implementation of a mutation model for ASP, creating several mutated programs from a reference program by randomly applying mutation operators to simulate common programming errors. These resulting programs, called mutants, are syntactical correct, but semantically faulty copies of the original program which are usable for many different tasks, e.g. mutation analysis. The tool is configured using an XML file that specifies the number of mutants to generate, the kind of mutation operations, the mode of their application (all or one), and so on. Currently, AspModificator is tailored for the gringo language. Nevertheless, as it is open source and offering a modular design, extensions to further ASP dialects or introduction of new modification operators should easily be possible.


AspModificator is developed in Java (version 6.0) and available as runnable Java archive or as source code:

AspModificator (runnable jar)

AspModificator (source code)


If you are using the executable jar file, no installation is needed. Just unzip the archive and prepare your configuration file.


Launching AspModificator

java -jar AspModificator.jar


java -jar AspModificator.jar -configFile <file> [options]

Possible arguments for AspModificator:

-i <file>    
-input <file>    
-inputFile <file>   file containing an asp-program which should be the base program for the modifications
-logging <logginglevel>   logging options - one of the following logging-levels:
"all", "debug", "error", "fatal", "info", "off", "trace", "warn"
-noComments   disables writing comments in the modified programs
-noCopies <number>   number of modified output-programs
-outputDir <dir>   the directory where the modified programs should be saved
-randomInit <number>   initialization-seed for the random-number generator

For a detailed manual, we refer to the "readme.txt" provided with the tool.


E-mail to: {oetsch,puehrer,schwengerer,tompits} "at"

Last update: 09.12.2011