A global scope provider that is both able to process the importURI attributes to establish cross links with other EMF models, and to handle references to JVM types.

TypeAndImportUriGlobalScopeProvider.java

import org.eclipse.emf.ecore.EReference;
import org.eclipse.emf.ecore.resource.Resource;
import org.eclipse.xtext.EcoreUtil2;
import org.eclipse.xtext.common.types.TypesPackage;
import org.eclipse.xtext.common.types.xtext.AbstractTypeScopeProvider;
import org.eclipse.xtext.common.types.xtext.ClasspathBasedTypeScopeProvider;
import org.eclipse.xtext.common.types.xtext.TypesAwareDefaultGlobalScopeProvider;
import org.eclipse.xtext.resource.IEObjectDescription;
import org.eclipse.xtext.scoping.IScope;
import org.eclipse.xtext.scoping.impl.ImportUriGlobalScopeProvider;
import com.google.common.base.Predicate;
import com.google.inject.Inject;

/**
 * A global scope provider that is both able to process the importURI attributes to establish cross links
 * with other EMF models, and to handle references to JVM types.
 * 
 * <p>This class is a subclass of {@link ImportUriGlobalScopeProvider} in order to get the importURI behavior
 * and delegates references to JVM types to an instance of AbstractTypeScopeProvider obtained through Guice.
 * 
 * @see TypesAwareDefaultGlobalScopeProvider where part of is getScope() function is duplicated here.
 * @see ClasspathBasedTypeScopeProvider
 * @see org.eclipse.xtext.common.types.xtext.ui.JdtBasedSimpleTypeScopeProvider
 *
 */
@SuppressWarnings( "restriction" )
public class TypeAndImportUriGlobalScopeProvider extends ImportUriGlobalScopeProvider {

    /*
     * AbstractTypeScopeProvider is bound to org.eclipse.xtext.common.types.xtext.ClasspathBasedTypeScopeProvider
     * in the "Standalone" setup and to org.eclipse.xtext.common.types.xtext.ui.JdtBasedSimpleTypeScopeProvider
     * int the IU setup. In both cases, the class AbstractTypeScopeProvider which is the usual global
     * scope provider when using the JVM types uses an AbstractTypeScopeProvider instance (through Guice) to
     * handle all references to JVM types : we do the same here.
     */
    @Inject
    private AbstractTypeScopeProvider typeScopeProvider;

    @Override
    public IScope getScope( Resource resource, EReference reference, Predicate<IEObjectDescription> filter ) {
        if( EcoreUtil2.isAssignableFrom( TypesPackage.Literals.JVM_TYPE, reference.getEReferenceType() ) ) {
            IScope typeScope = typeScopeProvider.getScope( resource, reference, filter );
            return typeScope;
        }
        else {
            return super.getScope( resource, reference, filter );
        }
    }
}