Importing Java class from Xtext dsl

Question

I am new to Xtext. I use a model class in my dsl like that:

Model abc:
 variable1
 variable2

and import class like that:

import a.b.c

What I want to do is, when I say import abc (which is a java class in same directory). Editor must recognise this abc class and refer it as a model like:

modelname = classname

variable names = variables in the class.

I wrote a different class too, which gets the references of variables in model class. So, if I say variable1 in that class and if there is no variable named variable1 in all models there will be a syntax error. It works when I write a model class in dsl, however I could not do it with using my import class.

Thanks for any help.

Answer 1

here may be a starting point

grammar org.xtext.example.mydsl.MyDsl with org.eclipse.xtext.xbase.Xbase

generate myDsl "http://www.xtext.org/example/mydsl/MyDsl"

import "http://www.eclipse.org/xtext/common/JavaVMTypes" as types

Model:
    imports=XImportSection?
    elements+=Element*
    ;

Element:
    "element" "{"
        "modelname" "=" type=JvmTypeReference
        "variable" "names" "=" memberReferences+=MemberReference ("," memberReferences+=MemberReference)*
    "}"
;

MemberReference:
    member=[types::JvmField|ID]
;

and following adaption of the scope provider

package org.xtext.example.mydsl.scoping

import org.eclipse.emf.ecore.EObject
import org.eclipse.emf.ecore.EReference
import org.eclipse.xtext.EcoreUtil2
import org.xtext.example.mydsl.myDsl.Element
import org.xtext.example.mydsl.myDsl.MyDslPackage
import org.eclipse.xtext.scoping.IScope
import org.eclipse.xtext.scoping.Scopes
import org.eclipse.xtext.common.types.JvmDeclaredType
import org.eclipse.xtext.naming.QualifiedName

class MyDslScopeProvider extends AbstractMyDslScopeProvider {

    override getScope(EObject context, EReference reference) {
        if (reference == MyDslPackage.Literals.MEMBER_REFERENCE__MEMBER) {
            val element = EcoreUtil2.getContainerOfType(context, Element)
            if (element != null)  {
                val type = element.type.type
                if (type instanceof JvmDeclaredType) {
                    return Scopes.scopeFor(type.declaredFields, [QualifiedName.create(simpleName)], IScope.NULLSCOPE)
                }
            }
            return IScope.NULLSCOPE
        }
        super.getScope(context, reference)
    }

}

proposal provider

class MyDslProposalProvider extends AbstractMyDslProposalProvider {

    override protected isKeywordWorthyToPropose(Keyword keyword) {
        true
    }

}