Epsilon and Sirius

Sirius is a powerful and robust EMF-based framework for developing graphical editors for domain-specific languages. By default, Sirius-based editors store semantic model information in standard EMF XMI format that is agnostic of Sirius, and diagram information (e.g. positions and colours of diagram elements) in a separate Sirius-specific XMI-based model with a .aird file extension. For instance, with the demo call centre menu editor shown below, the semantic model is saved in example.callcentre while the diagram information is stored in representations.aird.

The semantic model (example.callcentre) can be read and written by Epsilon programs just like any other EMF/XMI model. For example, this project demonstrates running EVL validation rules and an EGL model transformation against call centre models created with the Sirius-based editor. You can get a flavour of the validation rules and transformation below.

Code Generator (EGX)decision2java.eglValidation Constraints (EVL)

rule Model2App 
    transform m : Model {

    template : "model2java.egl"

    parameters : Map{}

    target : m.name.toLowerCase() + "/" + m.name.ftuc() + ".java"
}

rule Decision2Java 
    transform d : Decision {

    template : "decision2java.egl"

    parameters : Map{
        "m" = d.eContainer()
    }

    target : d.getJavaFileName()
}

// ...

operation Step getJavaFileName() {
    return self.eContainer.name.toLowerCase() + "/" + self.name.ftuc() + ".java";
}

package [%=m.name.toLowerCase()%];

import java.util.Scanner;

public class [%=d.name.ftuc()%] {

    public void run([%=m.name.ftuc()%] [%=m.name%]) {
        System.out.println("[%=d.text%]");

        [%for (t in d.outgoing){%]
        System.out.println("[%=loopCount%]. [%=t.text%]");
        [%}%]

        while (true) {
            String response = new Scanner(System.in).nextLine();
            [%for (t in d.outgoing){%]
            if (response.equals("[%=loopCount%]")) {
                [%=m.name%].get[%=t.to.name.ftuc()%]().run([%=m.name%]);
                return;
            }
            [%}%]
            System.out.println("Invalid option selected. Please select a valid option");
        }

    }

}

context Decision {

    constraint AtLeastTwoOutgoing {

        check: self.outgoing.size() >= 2

        message: "Decision " + self.text + 
            " must have at least 2 outgoing" +
            " transitions"
    }

}

context Model {

    constraint OneEntryPoint {

        check : self.steps.select(s|s.incoming.isEmpty()).size() = 1

        message : "The model has mutliple entry points: " +
            self.steps.select(s|s.incoming.isEmpty()).text.concat(", ")

    }
}

Integrated Model Validation

Sirius reuses EMF's validation framework, with which EVL integrates. Therefore, as shown here, you can use EVL to define validation constraints for your language and run them to produce error/warning markers on your Sirius diagrams with minimal configuration.