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Your First Project

This guide walks you through creating a minimal but complete language workbench in Jjodel: a simple class diagram language with classes, attributes, and associations.

Step 1 — Create a New Project

Section titled “Step 1 — Create a New Project”
  1. From the Dashboard, click the main menu (upper-left corner)
  2. Select New Project
  3. Give your project a name (e.g., MyFirstLanguage) and an optional description
  4. Click Create

Your project is now visible in the Dashboard. Click on it to enter the workspace.

Step 2 — Define Your Metamodel

Section titled “Step 2 — Define Your Metamodel”

The metamodel defines the abstract syntax of your language — what kinds of elements exist and how they relate to each other.

  1. In the workspace, open the Metamodel Editor
  2. Create a new class called Class
    • Add an attribute name of type String
  3. Create a second class called Attribute
    • Add an attribute name of type String
    • Add an attribute type of type String
  4. Create a containment reference from Class to Attribute
    • Name it attributes, set multiplicity to 0..*
  5. Create a third class called Association
    • Add a reference source pointing to Class
    • Add a reference target pointing to Class

You now have a metamodel that can describe class diagrams with classes, their attributes, and associations between classes.

Step 3 — Create a Model

Section titled “Step 3 — Create a Model”

A model is an instance of your metamodel — it contains concrete data conforming to the rules you defined.

  1. From the workspace, create a New Model
  2. Instantiate a Class element and name it Person
    • Add an Attribute named name with type String
    • Add an Attribute named age with type Integer
  3. Instantiate another Class element named Address
    • Add an Attribute named street with type String
  4. Create an Association from Person to Address

You have just created a simple domain model using the language you defined in Step 2.

Step 4 — Create a Viewpoint

Section titled “Step 4 — Create a Viewpoint”

Viewpoints define the concrete syntax — how model elements look in the graphical editor.

  1. Open the Viewpoint Editor
  2. Create a new viewpoint (e.g., ClassDiagramView)
  3. Define a view for Class:
    • Use a rectangle shape
    • Display the class name as a label
    • Show contained attributes inside the rectangle
  4. Define a view for Association:
    • Use a line connecting source and target classes
  5. Apply the viewpoint to your model

Your model is now rendered as a visual class diagram.

What You Built

Section titled “What You Built”

Congratulations — you have just created a complete language workbench:

  • A metamodel defining the abstract syntax (classes, attributes, associations)
  • A model containing domain-specific instances (Person, Address)
  • A viewpoint providing a graphical concrete syntax (class diagram notation)

This is the fundamental workflow in Jjodel. From here you can extend your language with validation rules, code generation, custom events, and more.

Next Steps

Section titled “Next Steps”