org.eclipse.emf.emfstore.client/src/org/eclipse/emf/emfstore/client/model/util/ResourceHelper.java

/*******************************************************************************
 * Copyright (c) 2008-2011 Chair for Applied Software Engineering,
 * Technische Universitaet Muenchen.
 * 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:
 ******************************************************************************/
package org.eclipse.emf.emfstore.client.model.util;

import java.io.IOException;
import java.util.Map;

import org.eclipse.emf.common.util.EList;
import org.eclipse.emf.common.util.TreeIterator;
import org.eclipse.emf.common.util.URI;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.resource.Resource;
import org.eclipse.emf.ecore.resource.impl.ResourceSetImpl;
import org.eclipse.emf.ecore.xmi.XMIResource;
import org.eclipse.emf.emfstore.client.model.ProjectSpace;
import org.eclipse.emf.emfstore.client.model.Workspace;
import org.eclipse.emf.emfstore.common.model.Project;
import org.eclipse.emf.emfstore.common.model.util.ModelUtil;

/**
 * Helper for resource operations.
 * 
 * @author wesendon
 */
public final class ResourceHelper {

	private ResourceHelper() {
		// blub
	}

	/**
	 * Gets an element from a resource.
	 * 
	 * @param <T> type of element
	 * @param absoluteFileName filepath of resource
	 * @param type .class from type
	 * @param options resource options
	 * @param index index of element in resource
	 * @return selected element
	 * @throws IOException in case of failure
	 */
	@SuppressWarnings("unchecked")
	public static <T extends EObject> T getElementFromResource(String absoluteFileName, Class<T> type,
		Map<?, ?> options, int index) throws IOException {
		ResourceSetImpl resourceSet = new ResourceSetImpl();
		// Resource resource = resourceSet.getResource(URI.createFileURI(absoluteFileName), false);
		Resource resource = resourceSet.createResource(URI.createFileURI(absoluteFileName));
		if (options != null) {
			resource.load(options);
		} else {
			resource.load(ModelUtil.getResourceLoadOptions());
		}
		EList<EObject> directContents = resource.getContents();

		// sanity check
		if (directContents.size() != 1 && (!type.isInstance(directContents.get(0)))) {
			throw new IOException("File is corrupt, does not contain a " + type.getName() + " .");
		}

		T object = (T) directContents.get(index);
		resource.getContents().remove(object);

		return object;
	}

	/**
	 * Gets an element from a resource.
	 * 
	 * @param <T> type of element
	 * @param absoluteFileName filepath of resource
	 * @param type .class from type
	 * @param index index of element in resource
	 * @return selected element
	 * @throws IOException in case of failure
	 */
	public static <T extends EObject> T getElementFromResource(String absoluteFileName, Class<T> type, int index)
		throws IOException {
		return getElementFromResource(absoluteFileName, type, null, index);
	}

	/**
	 * Puts an element into a new resource.
	 * 
	 * @param <T> element type
	 * @param element The element to be put
	 * @param absoluteFileName filepath of resource
	 * @throws IOException in case of failure
	 */
	public static <T extends EObject> void putElementIntoNewResource(String absoluteFileName, T element)
		throws IOException {
		ResourceSetImpl resourceSet = new ResourceSetImpl();
		Resource resource = resourceSet.createResource(URI.createFileURI(absoluteFileName));
		resource.getContents().add(element);
		resource.save(null);
	}

	/**
	 * Puts an element into a new resource.
	 * 
	 * @param <T> element type
	 * @param element The element to be put
	 * @param absoluteFileName filepath of resource
	 * @param project the associated project
	 * @throws IOException in case of failure
	 */
	public static <T extends EObject> void putElementIntoNewResourceWithProject(String absoluteFileName, T element,
		Project project) throws IOException {
		ResourceSetImpl resourceSet = new ResourceSetImpl();
		Resource resource = resourceSet.createResource(URI.createFileURI(absoluteFileName));
		resource.getContents().add(element);

		if (resource instanceof XMIResource) {
			XMIResource xmiResource = (XMIResource) resource;
			for (EObject modelElement : project.getAllModelElements()) {
				String modelElementId = project.getModelElementId(modelElement).getId();
				xmiResource.setID(modelElement, modelElementId);
			}
		}

		resource.save(null);
	}

	/**
	 * Puts an element into a new resource.
	 * 
	 * @param <T> element type
	 * @param workSpace the workspace to be put
	 * @param absoluteFileName filepath of resource
	 * @throws IOException in case of failure
	 */
	public static <T extends EObject> void putWorkspaceIntoNewResource(String absoluteFileName, Workspace workSpace)
		throws IOException {

		ResourceSetImpl resourceSet = new ResourceSetImpl();
		Resource resource = resourceSet.createResource(URI.createFileURI(absoluteFileName));
		resource.getContents().add(workSpace);

		if (resource instanceof XMIResource) {
			XMIResource xmiResource = (XMIResource) resource;

			for (ProjectSpace projectSpace : workSpace.getProjectSpaces()) {
				Project project = projectSpace.getProject();
				TreeIterator<EObject> it = project.eAllContents();
				while (it.hasNext()) {
					EObject modelElement = it.next();
					String modelElementId = project.getModelElementId(modelElement).getId();
					xmiResource.setID(modelElement, modelElementId);
				}
			}
		}

		resource.save(null);
	}
}