The Entities DSL with Xbase

We will now implement a modified version of the Entities DSL that we implemented in Chapter 2, Creating Your First Xtext Language. This will allow us to implement a more complex DSL where, inside entities, we can also write operations apart from attributes. This is inspired by the Xtext Domain-Model example.

Creating the project

We create a new Xtext project with the following settings:

• Project name: org.example.xbase.entities

• Name: org.example.xbase.entities.Entities

• Extensions: xentities

Defining attributes

We define the rules for attributes using some rules inherited from the Xbase grammar:

grammar org.example.xbase.entities.Entities
  with org.eclipse.xtext.xbase.Xbase

generate entities "http://www.example.org/xbase/entities/Entities"

Model:
  entities+=Entity*;

Entity:
'entity' name=ID ('extends' superType=JvmParameterizedTypeReference)? '{'
  attributes += Attribute*
'}';

Attribute:
  'attr' (type=JvmTypeReference)? name=ID
  ('=' initexpression=XExpression...