In the given example, the GroIMP argument is –project-tree.

All arguments given after the -jar core.jar are GroIMP arguments.

A non exhaustive list of common Java arguments used with GroIMP:

1. –project-tree this argument is used when GroIMP is run in Eclipse, it tells GroIMP to load classes under the local /PLUGIN/target/classes/ repositories where PLUGIN is the name of each directories at the root of GroIMP. This path is different when GroIMP is run after packaging. By default GroIMP load classes in ./plugins/PLUGIN/PLUGIN.jar where PLUGIN is the name of each plugins.
2. –headless this argument start GroIMP headless, i.e. without a graphical interface. Usually you also define the project to open as an argument (see 4.).
3. -a api this argument defines which application will be started (current available application: imp, cli, api). By default GroIMP starts with imp.
4. -p /path/to/a/directory/ link a directory to the list of loaded plugins.
5. path/to/a/model.gsz this argument requires to be used last. It gives a model to be opened after start.

It is possible to forward parameters from the command line to the GroIMP simulation using additional parameters beginning with an capital X. so for a variable called number with the value 5 the additional parameter would be -Xnumber=5. This value can than in the simulation be recalled by Main.getProperty(“number”)

A tutorial for this can be found here

Note: if you run GroIMP from Eclipse, the GroIMP arguments can be set in the Run Configuration…>x() = Arguments>Program arguments