Exercise: Define a new EMF model and create Java code from it #

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3.1. Project and initial model creation #

• Create a new project called de.vogella.emf.webpage.model via File > New  Project…​ > Ecore Modeling Project.

• This should open a visual editor for creating EMF models.

• Open the Properties view via the menu Window > Show View > Other…​ > Properties. This view allows you to modify the attributes of your model elements.

• Click on Class and click into the editor to create a new class. Create the Web, Webpage, Category and Article EClasses.

• Use the Attribute node to add the attribute called name to each class. This attribute should have the EString type. You can set the name under Properties > Semantic > Name and the type under Properties > Semantic > EType.

• Add the title, description and keywords attributes to the Web and Webpage model elements.

• We want to use the data type calendar in our model. Select Datatype and drag it into your model. Assign the name Calendar to it. Use java.util.Calendar as type parameter.

• Add a new Attribute called created to Article and use your new type.

• Under Relation select either Reference or Composition and create an arrow similar to the next picture.

• Make sure the upper bound is set to "-1" (* on the user interface) and that the Containment property is selected. In case Containment is not selected, you will not be able to add children to Web in the editor.

• Create these compositions from Web to Webpage, from Webpage to Category, and from Category to Article.

3.2. View Ecore diagram #

• Close the diagram and open the webpage.ecore file. The result should look like the following screenshot.

3.3. Set the package #

• Open the webpage.genmodel and select the Webpage node. Set the base package property to de.vogella.emf.webpage.model.