plugins/org.eclipse.emf.edapt.declaration/src/org/eclipse/emf/edapt/declaration/delegation/PropagateFeature.java

package org.eclipse.emf.edapt.declaration.delegation;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.emf.ecore.EReference;
import org.eclipse.emf.ecore.EStructuralFeature;
import org.eclipse.emf.edapt.declaration.EdaptConstraint;
import org.eclipse.emf.edapt.declaration.EdaptOperation;
import org.eclipse.emf.edapt.declaration.EdaptParameter;
import org.eclipse.emf.edapt.declaration.OperationImplementation;
import org.eclipse.emf.edapt.internal.common.MetamodelUtils;
import org.eclipse.emf.edapt.spi.migration.Instance;
import org.eclipse.emf.edapt.spi.migration.Metamodel;
import org.eclipse.emf.edapt.spi.migration.Model;

/**
 * {@description}
 *
 * @author herrmama
 * @author $Author$
 * @version $Rev$
 * @levd.rating YELLOW Hash: 1266620D095C774DDCCC00358C29DF9A
 */
@EdaptOperation(identifier = "propagateFeature", label = "Propagate Feature over References", description = "In the metamodel, a feature is propagated opposite to a number of references. More specifically, the feature is created in each of the classes which are sources of the references. In the model, the values of that feature are moved accordingly.")
public class PropagateFeature extends OperationImplementation {

	/** {@description} */
	@EdaptParameter(main = true, description = "The feature to be propagated")
	public EStructuralFeature mainFeature;

	/** {@description} */
	@EdaptParameter(description = "The references opposite to which the feature is propagated")
	public List<EReference> references = new ArrayList<EReference>();

	/** {@description} */
	@EdaptConstraint(restricts = "references", description = "Every reference has to target the class with the feature")
	public boolean checkReferencesType(EReference reference) {
		return reference.getEType() == mainFeature.getEContainingClass();
	}

	/** {@inheritDoc} */
	@Override
	public void execute(Metamodel metamodel, Model model) {
		// metamodel adaptation
		boolean first = true;
		final List<EStructuralFeature> features = new ArrayList<EStructuralFeature>();
		for (final EReference reference : references) {
			EStructuralFeature feature = null;
			if (first) {
				feature = mainFeature;
				first = false;
			} else {
				feature = MetamodelUtils.copy(mainFeature);
			}
			features.add(feature);
			reference.getEContainingClass().getEStructuralFeatures().add(
				feature);
		}

		// model migration
		for (int i = 0; i < references.size(); i++) {
			final EReference reference = references.get(i);
			final EStructuralFeature feature = features.get(i);
			for (final Instance instance : model.getAllInstances(reference
				.getEContainingClass())) {
				final Instance ref = instance.get(reference);
				if (ref != null) {
					final Object value = ref.unset(mainFeature);
					instance.set(feature, value);
				}
			}
		}
	}
}