Added selective EVL module example
diff --git a/examples/org.eclipse.epsilon.examples.standalone/src/org/eclipse/epsilon/examples/standalone/evl/SelectiveEvlModule.java b/examples/org.eclipse.epsilon.examples.standalone/src/org/eclipse/epsilon/examples/standalone/evl/SelectiveEvlModule.java
new file mode 100644
index 0000000..e11892a
--- /dev/null
+++ b/examples/org.eclipse.epsilon.examples.standalone/src/org/eclipse/epsilon/examples/standalone/evl/SelectiveEvlModule.java
@@ -0,0 +1,107 @@
+package org.eclipse.epsilon.examples.standalone.evl;
+
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.eclipse.emf.common.util.URI;
+import org.eclipse.emf.ecore.EAttribute;
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.EObject;
+import org.eclipse.emf.ecore.EcoreFactory;
+import org.eclipse.emf.ecore.EcorePackage;
+import org.eclipse.emf.ecore.resource.Resource;
+import org.eclipse.emf.ecore.resource.impl.ResourceSetImpl;
+import org.eclipse.emf.ecore.util.EcoreUtil;
+import org.eclipse.emf.ecore.xmi.impl.XMIResourceFactoryImpl;
+import org.eclipse.epsilon.common.module.ModuleElement;
+import org.eclipse.epsilon.common.parse.AST;
+import org.eclipse.epsilon.emc.emf.InMemoryEmfModel;
+import org.eclipse.epsilon.eol.exceptions.models.EolModelElementTypeNotFoundException;
+import org.eclipse.epsilon.eol.exceptions.models.EolModelNotFoundException;
+import org.eclipse.epsilon.eol.execute.context.IEolContext;
+import org.eclipse.epsilon.evl.EvlModule;
+import org.eclipse.epsilon.evl.dom.ConstraintContext;
+
+/**
+ * Demonstrates subclassing EvlModule to only check
+ * constraints against a selection of model elements
+ */
+
+public class SelectiveEvlModule extends EvlModule {
+
+ protected List<EObject> rootEObjects;
+
+ @Override
+ public ModuleElement adapt(AST cst, ModuleElement parentAst) {
+ ModuleElement moduleElement = super.adapt(cst, parentAst);
+ if (moduleElement instanceof ConstraintContext) {
+ return new SelectiveConstraintContext();
+ }
+ return moduleElement;
+ }
+
+ class SelectiveConstraintContext extends ConstraintContext {
+ @Override
+ public Collection<?> getAllOfSourceKind(IEolContext context)
+ throws EolModelElementTypeNotFoundException, EolModelNotFoundException {
+ // Only return a subset containing elements which are
+ // descendants of one of the root objects
+ return super.getAllOfSourceKind(context).stream().
+ filter(e -> shouldCheck(e)).collect(Collectors.toList());
+ }
+ }
+
+ protected boolean shouldCheck(Object object) {
+ // Only check elements which are decendants of one of the
+ // root objects
+ return EcoreUtil.isAncestor(rootEObjects, (EObject) object);
+ }
+
+ public void setRootEObjects(List<EObject> rootEObjects) {
+ this.rootEObjects = rootEObjects;
+ }
+
+ public List<EObject> getRootEObjects() {
+ return rootEObjects;
+ }
+
+ public static void main(String[] args) throws Exception {
+
+ SelectiveEvlModule module = new SelectiveEvlModule();
+
+ ResourceSetImpl resourceSet = new ResourceSetImpl();
+ resourceSet.getResourceFactoryRegistry().getExtensionToFactoryMap().put("*", new XMIResourceFactoryImpl());
+ Resource resource = resourceSet.createResource(URI.createURI("foo.ecore"));
+ resourceSet.getPackageRegistry().put(EcorePackage.eNS_URI, EcorePackage.eINSTANCE);
+
+ // Create 2 classes C1 and C2 with one attribute each
+ EClass c1 = EcoreFactory.eINSTANCE.createEClass();
+ c1.setName("C1");
+ EAttribute a1 = EcoreFactory.eINSTANCE.createEAttribute();
+ a1.setName("a1");
+ c1.getEStructuralFeatures().add(a1);
+
+ EClass c2 = EcoreFactory.eINSTANCE.createEClass();
+ c2.setName("C2");
+ EAttribute a2 = EcoreFactory.eINSTANCE.createEAttribute();
+ a2.setName("a2");
+ c2.getEStructuralFeatures().add(a2);
+
+ resource.getContents().add(c1);
+ resource.getContents().add(c2);
+
+ InMemoryEmfModel model = new InMemoryEmfModel(resource);
+
+ // Constraint for EAttibute
+ module.parse("context EAttribute { constraint Test { check {('Checking ' + self.name).println(); return true;} }}");
+ module.getContext().getModelRepository().addModel(model);
+
+ // Only elements under C1 (i.e. attribute a1) should be checked
+ module.setRootEObjects(Arrays.asList(c1));
+
+ module.execute();
+ }
+
+}
