EmfUtils.java

/*******************************************************************************
 * Copyright (c) 2005, 2007 committers of openArchitectureWare and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     committers of openArchitectureWare - initial API and implementation
 *******************************************************************************/
package org.eclipse.xtend.util.stdlib;

import java.util.Collection;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;

import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.EStructuralFeature;
import org.eclipse.emf.ecore.EStructuralFeature.Setting;
import org.eclipse.emf.ecore.util.EcoreUtil.CrossReferencer;
import org.eclipse.emf.ecore.xmi.XMLResource;

public class EmfUtils {
	
	/**
	 * Retrieves objects that reference a given object
	 * @param target The target object
	 * @return A list of objects referencing the target
	 */
	public static final List<EObject> getReferencingObjects(EObject target) {
		LinkedList<EObject> result = new LinkedList<EObject>(); 
		Collection<EStructuralFeature.Setting> settings = CrossReferencer.find(target.eResource().getContents()).get(target);
        if (settings == null) {
        	return Collections.emptyList();
        }
        for (Setting setting : settings) {
            result.add(setting.getEObject());
        }
		return result;
	}
	
	/**
	 * Retrieves an object's identifier. The object must be read from a
	 * XMLResource.
	 * 
	 * @param obj An object
	 * @return The object's id.
	 * @since 4.3.1
	 */
	public static String getID(EObject obj) {
		return (obj.eResource() != null && obj.eResource() instanceof XMLResource) ? ((XMLResource) obj.eResource()).getID(obj) : null;
	}
	
}