plugins/org.eclipse.emf.edapt.history/src/org/eclipse/emf/edapt/migration/execution/Migrator.java - gerrit/edapt/org.eclipse.emf.edapt - Git at Google

 /*******************************************************************************
  * Copyright (c) 2007, 2010 BMW Car IT, Technische Universitaet Muenchen, and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
  * BMW Car IT - Initial API and implementation
  * Technische Universitaet Muenchen - Major refactoring and extension
  *******************************************************************************/
 package org.eclipse.emf.edapt.migration.execution;

 import java.io.File;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Set;

 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.emf.common.util.URI;
 import org.eclipse.emf.ecore.EObject;
 import org.eclipse.emf.ecore.EPackage;
 import org.eclipse.emf.ecore.EcorePackage;
 import org.eclipse.emf.ecore.resource.ResourceSet;
 import org.eclipse.emf.edapt.common.IResourceSetFactory;
 import org.eclipse.emf.edapt.common.IResourceSetProcessor;
 import org.eclipse.emf.edapt.declaration.LibraryImplementation;
 import org.eclipse.emf.edapt.declaration.OperationImplementation;
 import org.eclipse.emf.edapt.history.reconstruction.EcoreForwardReconstructor;
 import org.eclipse.emf.edapt.history.util.HistoryUtils;
 import org.eclipse.emf.edapt.internal.common.MetamodelUtils;
 import org.eclipse.emf.edapt.internal.common.ResourceSetFactoryImpl;
 import org.eclipse.emf.edapt.internal.common.ResourceUtils;
 import org.eclipse.emf.edapt.internal.declaration.OperationRegistry;
 import org.eclipse.emf.edapt.internal.migration.execution.IClassLoader;
 import org.eclipse.emf.edapt.internal.migration.execution.ValidationLevel;
 import org.eclipse.emf.edapt.internal.migration.execution.internal.ClassLoaderFacade;
 import org.eclipse.emf.edapt.internal.migration.execution.internal.MigrationReconstructor;
 import org.eclipse.emf.edapt.internal.migration.execution.internal.MigratorCommandLine;
 import org.eclipse.emf.edapt.internal.migration.execution.internal.WrappedMigrationException;
 import org.eclipse.emf.edapt.internal.migration.internal.BackupUtils;
 import org.eclipse.emf.edapt.internal.migration.internal.MaterializingBackwardConverter;
 import org.eclipse.emf.edapt.internal.migration.internal.Persistency;
 import org.eclipse.emf.edapt.internal.migration.internal.PrintStreamProgressMonitor;
 import org.eclipse.emf.edapt.migration.CustomMigration;
 import org.eclipse.emf.edapt.migration.MigrationException;
 import org.eclipse.emf.edapt.migration.ReleaseUtils;
 import org.eclipse.emf.edapt.spi.history.Delete;
 import org.eclipse.emf.edapt.spi.history.History;
 import org.eclipse.emf.edapt.spi.history.HistoryPackage;
 import org.eclipse.emf.edapt.spi.history.Release;
 import org.eclipse.emf.edapt.spi.migration.Metamodel;
 import org.eclipse.emf.edapt.spi.migration.Model;

 /**
  * Migrator to migrate a model from a previous to the current release.
  *
  * @author herrmama
  * @author $Author$
  * @version $Rev$
  * @levd.rating YELLOW Hash: B6F49196D15E37A963EB83E9543D5770
  */
 public class Migrator {

 	/** Metamodel history no which this migrator is based. */
 	private History history;

 	/** Mapping of namespace URIs to releases. */
 	private HashMap<String, Set<Release>> releaseMap;

 	/** Classloader to load {@link CustomMigration}s. */
 	private final IClassLoader classLoader;

 	/** Factory to create {@link ResourceSet}s for custom serialization. */
 	private IResourceSetFactory resourceSetFactory = new ResourceSetFactoryImpl();

 	/** Validation level. */
 	private ValidationLevel level = ValidationLevel.CUSTOM_MIGRATION;

 	private IResourceSetProcessor postLoadProcessor;

 	/** Constructor. */
 	public Migrator(URI historyURI, IClassLoader classLoader)
 		throws MigrationException {
 		HistoryPackage.eINSTANCE.getHistory();
 		try {
 			history = ResourceUtils.loadElement(historyURI);
 		} catch (final IOException e) {
 			throw new MigrationException("History could not be loaded", e); //$NON-NLS-1$
 		}
 		this.classLoader = classLoader;
 		init();
 	}

 	/** Constructor. */
 	public Migrator(History history, IClassLoader classLoader) {
 		this.history = history;
 		this.classLoader = classLoader;
 		init();
 	}

 	/** Initialize release map for the migrator. */
 	private void init() {
 		releaseMap = new HashMap<String, Set<Release>>();
 		final Map<EPackage, String> packageMap = new HashMap<EPackage, String>();

 		for (final Release release : history.getReleases()) {
 			if (!release.isLastRelease()) {
 				updatePackages(release, packageMap);
 				registerRelease(release, packageMap);
 			}
 		}
 	}

 	/** Register a package for a certain release. */
 	private void registerRelease(Release release,
 		Map<EPackage, String> packageMap) {
 		for (final Entry<EPackage, String> entry : packageMap.entrySet()) {
 			final String nsURI = entry.getValue();
 			Set<Release> releases = releaseMap.get(nsURI);
 			if (releases == null) {
 				releases = new HashSet<Release>();
 				releaseMap.put(nsURI, releases);
 			}
 			releases.add(release);
 		}
 	}

 	/** Update the namespace URIs based on the changes during a release. */
 	private void updatePackages(Release release,
 		Map<EPackage, String> packageMap) {
 		for (final Iterator<EObject> i = release.eAllContents(); i.hasNext();) {
 			final EObject element = i.next();
 			if (element instanceof org.eclipse.emf.edapt.spi.history.Set) {
 				final org.eclipse.emf.edapt.spi.history.Set set = (org.eclipse.emf.edapt.spi.history.Set) element;
 				if (set.getFeature() == EcorePackage.eINSTANCE
 					.getEPackage_NsURI()) {
 					final EPackage ePackage = (EPackage) set.getElement();
 					final String nsURI = (String) set.getValue();
 					packageMap.put(ePackage, nsURI);
 				}
 			} else if (element instanceof Delete) {
 				final Delete delete = (Delete) element;
 				packageMap.remove(delete.getElement());
 			}
 		}
 	}

 	/**
 	 * Migrate a model based on a set of {@link URI}.
 	 *
 	 * @param modelURIs
 	 * @param sourceRelease
 	 *            Release to which the model conforms
 	 * @param targetRelease
 	 *            Release to which the model should be migrated (use null for
 	 *            the newest release)
 	 * @param monitor
 	 *            Progress monitor
 	 */
 	public void migrateAndSave(List<URI> modelURIs, Release sourceRelease,
 		Release targetRelease, IProgressMonitor monitor)
 		throws MigrationException {
 		this.migrateAndSave(modelURIs, sourceRelease, targetRelease, monitor, null);
 	}

 	/**
 	 * Migrate a model based on a set of {@link URI}.
 	 *
 	 * @param modelURIs
 	 * @param sourceRelease
 	 *            Release to which the model conforms
 	 * @param targetRelease
 	 *            Release to which the model should be migrated (use null for
 	 *            the newest release)
 	 * @param monitor
 	 *            Progress monitor
 	 * @param options
 	 *            Options to pass to the ResourceSet when saving
 	 * @since 1.1
 	 */
 	public void migrateAndSave(List<URI> modelURIs, Release sourceRelease,
 		Release targetRelease, IProgressMonitor monitor, Map<String, Object> options)
 		throws MigrationException {
 		final Model model = migrate(modelURIs, sourceRelease, targetRelease, monitor);
 		if (model == null) {
 			throw new MigrationException("Model is up-to-date", null); //$NON-NLS-1$
 		}
 		try {
 			Persistency.saveModel(model, options);
 		} catch (final IOException e) {
 			throw new MigrationException("Model could not be saved", e); //$NON-NLS-1$
 		}
 	}

 	/**
 	 * Migrate a model based on a set of {@link URI}s and load it afterwards.
 	 *
 	 * @param modelURIs
 	 *            The set of {@link URI}
 	 * @param sourceRelease
 	 *            Release to which the model conforms
 	 * @param targetRelease
 	 *            Release to which the model should be migrated (use null for
 	 *            the newest release)
 	 * @param monitor
 	 *            Progress monitor
 	 * @return The model in a {@link ResourceSet}
 	 */
 	public ResourceSet migrateAndLoad(List<URI> modelURIs,
 		Release sourceRelease, Release targetRelease,
 		IProgressMonitor monitor) throws MigrationException {
 		final Model model = migrate(modelURIs, sourceRelease, targetRelease, monitor);
 		if (model == null) {
 			return null;
 		}
 		final MaterializingBackwardConverter converter = new MaterializingBackwardConverter();
 		return converter.convert(model);
 	}

 	/** Get the latest release. */
 	public Release getLatestRelease() {
 		final List<Release> releases = history.getReleases();
 		return releases.get(releases.size() - 2);
 	}

 	/**
 	 * Migrate a model based on a set of {@link URI}s.
 	 *
 	 * @param modelURIs
 	 *            The set of {@link URI}
 	 * @param sourceRelease
 	 *            Release to which the model conforms
 	 * @param targetRelease
 	 *            Release to which the model should be migrated (use null for
 	 *            the newest release)
 	 * @param monitor
 	 *            Progress monitor
 	 * @return The model in the generic structure
 	 */
 	private Model migrate(List<URI> modelURIs, Release sourceRelease,
 		Release targetRelease, IProgressMonitor monitor)
 		throws MigrationException {
 		try {
 			if (targetRelease == null) {
 				targetRelease = getLatestRelease();
 			}
 			if (sourceRelease == targetRelease) {
 				return null;
 			}

 			monitor.beginTask("Migrate", //$NON-NLS-1$
 				numberOfSteps(sourceRelease, targetRelease));
 			final EcoreForwardReconstructor reconstructor = new EcoreForwardReconstructor(
 				URI.createFileURI("test")); //$NON-NLS-1$
 			final MigrationReconstructor migrationReconstructor = new MigrationReconstructor(
 				modelURIs, sourceRelease, targetRelease, monitor,
 				classLoader, level, resourceSetFactory, postLoadProcessor);
 			reconstructor.addReconstructor(migrationReconstructor);

 			reconstructor.reconstruct(targetRelease, false);

 			final Model model = migrationReconstructor.getModel();
 			return model;
 		} catch (final WrappedMigrationException e) {
 			throw e.getCause();
 		} finally {
 			monitor.done();
 		}
 	}

 	/** Returns the length of the migration in terms of the steps. */
 	private int numberOfSteps(Release sourceRelease, Release targetRelease) {
 		int size = 0;
 		boolean inRelease = false;
 		for (final Release release : history.getReleases()) {
 			if (inRelease) {
 				size += release.getChanges().size();
 			}
 			if (release == sourceRelease) {
 				inRelease = true;
 			}
 			if (release == targetRelease) {
 				break;
 			}
 		}
 		return size;
 	}

 	/** Get the release of a model based on {@link URI}. */
 	public Set<Release> getRelease(URI modelURI) {
 		final String nsURI = ReleaseUtils.getNamespaceURI(modelURI);
 		return releaseMap.containsKey(nsURI) ? releaseMap.get(nsURI)
 			: Collections.<Release> emptySet();
 	}

 	/**
 	 * Get the release of a model based on a set of namespace URIs.
 	 *
 	 * @since 1.2
 	 */
 	public Set<Release> getRelease(Set<String> nsURIs) {
 		final Set<Release> releases = new LinkedHashSet<Release>();
 		for (final String nsURI : nsURIs) {
 			final Set<Release> set = getReleaseMap().get(nsURI);
 			if (set == null || set.isEmpty()) {
 				continue;
 			}
 			if (releases.isEmpty()) {
 				releases.addAll(set);
 			} else {
 				releases.retainAll(set);
 			}
 		}
 		return releases;
 	}

 	/** Get the release map from NS-URI to releases */
 	public Map<String, Set<Release>> getReleaseMap() {
 		return releaseMap;
 	}

 	/** Get the release with a certain number. */
 	public Release getRelease(int number) {
 		if (number < 0 || number >= history.getReleases().size()) {
 			return null;
 		}
 		return history.getReleases().get(number);
 	}

 	/** Get all releases. */
 	public List<Release> getReleases() {
 		final List<Release> releases = new ArrayList<Release>();
 		releases.addAll(history.getReleases());
 		releases.remove(history.getLastRelease());
 		return releases;
 	}

 	/** Get set of namespace URIs. */
 	public Set<String> getNsURIs() {
 		return releaseMap.keySet();
 	}

 	// CB TODO SHOULD BE API or Adapter, this is called from MigrateHandler.

 	/** Returns the metamodel for a release. */
 	public Metamodel getMetamodel(Release release) {
 		final EcoreForwardReconstructor reconstructor = new EcoreForwardReconstructor(
 			URI.createFileURI("test")); //$NON-NLS-1$
 		reconstructor.reconstruct(release, false);
 		final URI metamodelURI = URI.createFileURI(new File("metamodel." //$NON-NLS-1$
 			+ ResourceUtils.ECORE_FILE_EXTENSION).getAbsolutePath());
 		final List<EPackage> rootPackages = ResourceUtils.getRootElements(
 			reconstructor.getResourceSet(), EPackage.class);
 		final ResourceSet resourceSet = MetamodelUtils
 			.createIndependentMetamodelCopy(rootPackages, metamodelURI);
 		return Persistency.loadMetamodel(resourceSet);
 	}

 	/** Set the validation level. */
 	public void setLevel(ValidationLevel level) {
 		this.level = level;
 	}

 	/** Main method to perform migrations. */
 	public static void main(String[] args) {

 		final MigratorCommandLine commandLine = new MigratorCommandLine(args);
 		final List<URI> modelURIs = commandLine.getModelURIs();
 		final int sourceReleaseNumber = commandLine.getSourceReleaseNumber();
 		final int targetReleaseNumber = commandLine.getTargetReleaseNumber();

 		try {
 			for (final Class<? extends LibraryImplementation> library : commandLine
 				.getLibraries()) {
 				OperationRegistry.getInstance().registerLibrary(library);
 			}
 			for (final Class<? extends OperationImplementation> operation : commandLine
 				.getOperations()) {
 				OperationRegistry.getInstance().registerOperation(operation);
 			}

 			final Migrator migrator = new Migrator(commandLine.getHistoryURI(),
 				new ClassLoaderFacade(Thread.currentThread()
 					.getContextClassLoader()));
 			migrator.setLevel(commandLine.getLevel());

 			final Set<Release> releases = migrator.getRelease(modelURIs.get(0));
 			Release sourceRelease = null;
 			if (sourceReleaseNumber != -1) {
 				sourceRelease = HistoryUtils.getRelease(releases,
 					sourceReleaseNumber);
 			} else {
 				sourceRelease = releases.iterator().next();
 			}

 			if (commandLine.isBackup()) {
 				final Metamodel metamodel = migrator.getMetamodel(sourceRelease);
 				try {
 					BackupUtils.backup(modelURIs, metamodel);
 				} catch (final IOException e) {
 					System.err.println(e.getMessage());
 				}
 			}

 			final Release targetRelease = migrator.getRelease(targetReleaseNumber);

 			migrator.migrateAndSave(modelURIs, sourceRelease, targetRelease,
 				new PrintStreamProgressMonitor(System.out));
 		} catch (final MigrationException e) {
 			System.err.println(e.getMessage());
 			System.err.println(e.getCause().getMessage());
 		}
 	}

 	/** Set the factory to create {@link ResourceSet}s for custom serialization. */
 	public void setResourceSetFactory(IResourceSetFactory resourceSetFactory) {
 		if (resourceSetFactory != null) {
 			this.resourceSetFactory = resourceSetFactory;
 		}
 	}

 	/** Get the factory to create {@link ResourceSet}s for custom serialization. */
 	public IResourceSetFactory getResourceSetFactory() {
 		return resourceSetFactory;
 	}

 	/**
 	 * The given processor will be called after the outdated model was loaded. It will be called before Edapt translates
 	 * the dynamic EMF model into its internal representation required for the migration. Hence this processor may be
 	 * used to modify the to be migrated model before the actual migrations starts.
 	 *
 	 * @since 1.3
 	 */
 	public void setPostLoadModelProcessor(IResourceSetProcessor postLoadProcessor) {
 		this.postLoadProcessor = postLoadProcessor;
 	}

 	/**
 	 * The post load model processor.
 	 *
 	 * @since 1.3
 	 */
 	public IResourceSetProcessor getPostLoadModelProcessor() {
 		return postLoadProcessor;
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2007, 2010 BMW Car IT, Technische Universitaet Muenchen, and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License 2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors:
	* BMW Car IT - Initial API and implementation
	* Technische Universitaet Muenchen - Major refactoring and extension
	*******************************************************************************/
	package org.eclipse.emf.edapt.migration.execution;

	import java.io.File;
	import java.io.IOException;
	import java.util.ArrayList;
	import java.util.Collections;
	import java.util.HashMap;
	import java.util.HashSet;
	import java.util.Iterator;
	import java.util.LinkedHashSet;
	import java.util.List;
	import java.util.Map;
	import java.util.Map.Entry;
	import java.util.Set;

	import org.eclipse.core.runtime.IProgressMonitor;
	import org.eclipse.emf.common.util.URI;
	import org.eclipse.emf.ecore.EObject;
	import org.eclipse.emf.ecore.EPackage;
	import org.eclipse.emf.ecore.EcorePackage;
	import org.eclipse.emf.ecore.resource.ResourceSet;
	import org.eclipse.emf.edapt.common.IResourceSetFactory;
	import org.eclipse.emf.edapt.common.IResourceSetProcessor;
	import org.eclipse.emf.edapt.declaration.LibraryImplementation;
	import org.eclipse.emf.edapt.declaration.OperationImplementation;
	import org.eclipse.emf.edapt.history.reconstruction.EcoreForwardReconstructor;
	import org.eclipse.emf.edapt.history.util.HistoryUtils;
	import org.eclipse.emf.edapt.internal.common.MetamodelUtils;
	import org.eclipse.emf.edapt.internal.common.ResourceSetFactoryImpl;
	import org.eclipse.emf.edapt.internal.common.ResourceUtils;
	import org.eclipse.emf.edapt.internal.declaration.OperationRegistry;
	import org.eclipse.emf.edapt.internal.migration.execution.IClassLoader;
	import org.eclipse.emf.edapt.internal.migration.execution.ValidationLevel;
	import org.eclipse.emf.edapt.internal.migration.execution.internal.ClassLoaderFacade;
	import org.eclipse.emf.edapt.internal.migration.execution.internal.MigrationReconstructor;
	import org.eclipse.emf.edapt.internal.migration.execution.internal.MigratorCommandLine;
	import org.eclipse.emf.edapt.internal.migration.execution.internal.WrappedMigrationException;
	import org.eclipse.emf.edapt.internal.migration.internal.BackupUtils;
	import org.eclipse.emf.edapt.internal.migration.internal.MaterializingBackwardConverter;
	import org.eclipse.emf.edapt.internal.migration.internal.Persistency;
	import org.eclipse.emf.edapt.internal.migration.internal.PrintStreamProgressMonitor;
	import org.eclipse.emf.edapt.migration.CustomMigration;
	import org.eclipse.emf.edapt.migration.MigrationException;
	import org.eclipse.emf.edapt.migration.ReleaseUtils;
	import org.eclipse.emf.edapt.spi.history.Delete;
	import org.eclipse.emf.edapt.spi.history.History;
	import org.eclipse.emf.edapt.spi.history.HistoryPackage;
	import org.eclipse.emf.edapt.spi.history.Release;
	import org.eclipse.emf.edapt.spi.migration.Metamodel;
	import org.eclipse.emf.edapt.spi.migration.Model;

	/**
	* Migrator to migrate a model from a previous to the current release.
	*
	* @author herrmama
	* @author $Author$
	* @version $Rev$
	* @levd.rating YELLOW Hash: B6F49196D15E37A963EB83E9543D5770
	*/
	public class Migrator {

	/** Metamodel history no which this migrator is based. */
	private History history;

	/** Mapping of namespace URIs to releases. */
	private HashMap<String, Set<Release>> releaseMap;

	/** Classloader to load {@link CustomMigration}s. */
	private final IClassLoader classLoader;

	/** Factory to create {@link ResourceSet}s for custom serialization. */
	private IResourceSetFactory resourceSetFactory = new ResourceSetFactoryImpl();

	/** Validation level. */
	private ValidationLevel level = ValidationLevel.CUSTOM_MIGRATION;

	private IResourceSetProcessor postLoadProcessor;

	/** Constructor. */
	public Migrator(URI historyURI, IClassLoader classLoader)
	throws MigrationException {
	HistoryPackage.eINSTANCE.getHistory();
	try {
	history = ResourceUtils.loadElement(historyURI);
	} catch (final IOException e) {
	throw new MigrationException("History could not be loaded", e); //$NON-NLS-1$
	}
	this.classLoader = classLoader;
	init();
	}

	/** Constructor. */
	public Migrator(History history, IClassLoader classLoader) {
	this.history = history;
	this.classLoader = classLoader;
	init();
	}

	/** Initialize release map for the migrator. */
	private void init() {
	releaseMap = new HashMap<String, Set<Release>>();
	final Map<EPackage, String> packageMap = new HashMap<EPackage, String>();

	for (final Release release : history.getReleases()) {
	if (!release.isLastRelease()) {
	updatePackages(release, packageMap);
	registerRelease(release, packageMap);
	}
	}
	}

	/** Register a package for a certain release. */
	private void registerRelease(Release release,
	Map<EPackage, String> packageMap) {
	for (final Entry<EPackage, String> entry : packageMap.entrySet()) {
	final String nsURI = entry.getValue();
	Set<Release> releases = releaseMap.get(nsURI);
	if (releases == null) {
	releases = new HashSet<Release>();
	releaseMap.put(nsURI, releases);
	}
	releases.add(release);
	}
	}

	/** Update the namespace URIs based on the changes during a release. */
	private void updatePackages(Release release,
	Map<EPackage, String> packageMap) {
	for (final Iterator<EObject> i = release.eAllContents(); i.hasNext();) {
	final EObject element = i.next();
	if (element instanceof org.eclipse.emf.edapt.spi.history.Set) {
	final org.eclipse.emf.edapt.spi.history.Set set = (org.eclipse.emf.edapt.spi.history.Set) element;
	if (set.getFeature() == EcorePackage.eINSTANCE
	.getEPackage_NsURI()) {
	final EPackage ePackage = (EPackage) set.getElement();
	final String nsURI = (String) set.getValue();
	packageMap.put(ePackage, nsURI);
	}
	} else if (element instanceof Delete) {
	final Delete delete = (Delete) element;
	packageMap.remove(delete.getElement());
	}
	}
	}

	/**
	* Migrate a model based on a set of {@link URI}.
	*
	* @param modelURIs
	* @param sourceRelease
	* Release to which the model conforms
	* @param targetRelease
	* Release to which the model should be migrated (use null for
	* the newest release)
	* @param monitor
	* Progress monitor
	*/
	public void migrateAndSave(List<URI> modelURIs, Release sourceRelease,
	Release targetRelease, IProgressMonitor monitor)
	throws MigrationException {
	this.migrateAndSave(modelURIs, sourceRelease, targetRelease, monitor, null);
	}

	/**
	* Migrate a model based on a set of {@link URI}.
	*
	* @param modelURIs
	* @param sourceRelease
	* Release to which the model conforms
	* @param targetRelease
	* Release to which the model should be migrated (use null for
	* the newest release)
	* @param monitor
	* Progress monitor
	* @param options
	* Options to pass to the ResourceSet when saving
	* @since 1.1
	*/
	public void migrateAndSave(List<URI> modelURIs, Release sourceRelease,
	Release targetRelease, IProgressMonitor monitor, Map<String, Object> options)
	throws MigrationException {
	final Model model = migrate(modelURIs, sourceRelease, targetRelease, monitor);
	if (model == null) {
	throw new MigrationException("Model is up-to-date", null); //$NON-NLS-1$
	}
	try {
	Persistency.saveModel(model, options);
	} catch (final IOException e) {
	throw new MigrationException("Model could not be saved", e); //$NON-NLS-1$
	}
	}

	/**
	* Migrate a model based on a set of {@link URI}s and load it afterwards.
	*
	* @param modelURIs
	* The set of {@link URI}
	* @param sourceRelease
	* Release to which the model conforms
	* @param targetRelease
	* Release to which the model should be migrated (use null for
	* the newest release)
	* @param monitor
	* Progress monitor
	* @return The model in a {@link ResourceSet}
	*/
	public ResourceSet migrateAndLoad(List<URI> modelURIs,
	Release sourceRelease, Release targetRelease,
	IProgressMonitor monitor) throws MigrationException {
	final Model model = migrate(modelURIs, sourceRelease, targetRelease, monitor);
	if (model == null) {
	return null;
	}
	final MaterializingBackwardConverter converter = new MaterializingBackwardConverter();
	return converter.convert(model);
	}

	/** Get the latest release. */
	public Release getLatestRelease() {
	final List<Release> releases = history.getReleases();
	return releases.get(releases.size() - 2);
	}

	/**
	* Migrate a model based on a set of {@link URI}s.
	*
	* @param modelURIs
	* The set of {@link URI}
	* @param sourceRelease
	* Release to which the model conforms
	* @param targetRelease
	* Release to which the model should be migrated (use null for
	* the newest release)
	* @param monitor
	* Progress monitor
	* @return The model in the generic structure
	*/
	private Model migrate(List<URI> modelURIs, Release sourceRelease,
	Release targetRelease, IProgressMonitor monitor)
	throws MigrationException {
	try {
	if (targetRelease == null) {
	targetRelease = getLatestRelease();
	}
	if (sourceRelease == targetRelease) {
	return null;
	}

	monitor.beginTask("Migrate", //$NON-NLS-1$
	numberOfSteps(sourceRelease, targetRelease));
	final EcoreForwardReconstructor reconstructor = new EcoreForwardReconstructor(
	URI.createFileURI("test")); //$NON-NLS-1$
	final MigrationReconstructor migrationReconstructor = new MigrationReconstructor(
	modelURIs, sourceRelease, targetRelease, monitor,
	classLoader, level, resourceSetFactory, postLoadProcessor);
	reconstructor.addReconstructor(migrationReconstructor);

	reconstructor.reconstruct(targetRelease, false);

	final Model model = migrationReconstructor.getModel();
	return model;
	} catch (final WrappedMigrationException e) {
	throw e.getCause();
	} finally {
	monitor.done();
	}
	}

	/** Returns the length of the migration in terms of the steps. */
	private int numberOfSteps(Release sourceRelease, Release targetRelease) {
	int size = 0;
	boolean inRelease = false;
	for (final Release release : history.getReleases()) {
	if (inRelease) {
	size += release.getChanges().size();
	}
	if (release == sourceRelease) {
	inRelease = true;
	}
	if (release == targetRelease) {
	break;
	}
	}
	return size;
	}

	/** Get the release of a model based on {@link URI}. */
	public Set<Release> getRelease(URI modelURI) {
	final String nsURI = ReleaseUtils.getNamespaceURI(modelURI);
	return releaseMap.containsKey(nsURI) ? releaseMap.get(nsURI)
	: Collections.<Release> emptySet();
	}

	/**
	* Get the release of a model based on a set of namespace URIs.
	*
	* @since 1.2
	*/
	public Set<Release> getRelease(Set<String> nsURIs) {
	final Set<Release> releases = new LinkedHashSet<Release>();
	for (final String nsURI : nsURIs) {
	final Set<Release> set = getReleaseMap().get(nsURI);
	if (set == null \|\| set.isEmpty()) {
	continue;
	}
	if (releases.isEmpty()) {
	releases.addAll(set);
	} else {
	releases.retainAll(set);
	}
	}
	return releases;
	}

	/** Get the release map from NS-URI to releases */
	public Map<String, Set<Release>> getReleaseMap() {
	return releaseMap;
	}

	/** Get the release with a certain number. */
	public Release getRelease(int number) {
	if (number < 0 \|\| number >= history.getReleases().size()) {
	return null;
	}
	return history.getReleases().get(number);
	}

	/** Get all releases. */
	public List<Release> getReleases() {
	final List<Release> releases = new ArrayList<Release>();
	releases.addAll(history.getReleases());
	releases.remove(history.getLastRelease());
	return releases;
	}

	/** Get set of namespace URIs. */
	public Set<String> getNsURIs() {
	return releaseMap.keySet();
	}

	// CB TODO SHOULD BE API or Adapter, this is called from MigrateHandler.

	/** Returns the metamodel for a release. */
	public Metamodel getMetamodel(Release release) {
	final EcoreForwardReconstructor reconstructor = new EcoreForwardReconstructor(
	URI.createFileURI("test")); //$NON-NLS-1$
	reconstructor.reconstruct(release, false);
	final URI metamodelURI = URI.createFileURI(new File("metamodel." //$NON-NLS-1$
	+ ResourceUtils.ECORE_FILE_EXTENSION).getAbsolutePath());
	final List<EPackage> rootPackages = ResourceUtils.getRootElements(
	reconstructor.getResourceSet(), EPackage.class);
	final ResourceSet resourceSet = MetamodelUtils
	.createIndependentMetamodelCopy(rootPackages, metamodelURI);
	return Persistency.loadMetamodel(resourceSet);
	}

	/** Set the validation level. */
	public void setLevel(ValidationLevel level) {
	this.level = level;
	}

	/** Main method to perform migrations. */
	public static void main(String[] args) {

	final MigratorCommandLine commandLine = new MigratorCommandLine(args);
	final List<URI> modelURIs = commandLine.getModelURIs();
	final int sourceReleaseNumber = commandLine.getSourceReleaseNumber();
	final int targetReleaseNumber = commandLine.getTargetReleaseNumber();

	try {
	for (final Class<? extends LibraryImplementation> library : commandLine
	.getLibraries()) {
	OperationRegistry.getInstance().registerLibrary(library);
	}
	for (final Class<? extends OperationImplementation> operation : commandLine
	.getOperations()) {
	OperationRegistry.getInstance().registerOperation(operation);
	}

	final Migrator migrator = new Migrator(commandLine.getHistoryURI(),
	new ClassLoaderFacade(Thread.currentThread()
	.getContextClassLoader()));
	migrator.setLevel(commandLine.getLevel());

	final Set<Release> releases = migrator.getRelease(modelURIs.get(0));
	Release sourceRelease = null;
	if (sourceReleaseNumber != -1) {
	sourceRelease = HistoryUtils.getRelease(releases,
	sourceReleaseNumber);
	} else {
	sourceRelease = releases.iterator().next();
	}

	if (commandLine.isBackup()) {
	final Metamodel metamodel = migrator.getMetamodel(sourceRelease);
	try {
	BackupUtils.backup(modelURIs, metamodel);
	} catch (final IOException e) {
	System.err.println(e.getMessage());
	}
	}

	final Release targetRelease = migrator.getRelease(targetReleaseNumber);

	migrator.migrateAndSave(modelURIs, sourceRelease, targetRelease,
	new PrintStreamProgressMonitor(System.out));
	} catch (final MigrationException e) {
	System.err.println(e.getMessage());
	System.err.println(e.getCause().getMessage());
	}
	}

	/** Set the factory to create {@link ResourceSet}s for custom serialization. */
	public void setResourceSetFactory(IResourceSetFactory resourceSetFactory) {
	if (resourceSetFactory != null) {
	this.resourceSetFactory = resourceSetFactory;
	}
	}

	/** Get the factory to create {@link ResourceSet}s for custom serialization. */
	public IResourceSetFactory getResourceSetFactory() {
	return resourceSetFactory;
	}

	/**
	* The given processor will be called after the outdated model was loaded. It will be called before Edapt translates
	* the dynamic EMF model into its internal representation required for the migration. Hence this processor may be
	* used to modify the to be migrated model before the actual migrations starts.
	*
	* @since 1.3
	*/
	public void setPostLoadModelProcessor(IResourceSetProcessor postLoadProcessor) {
	this.postLoadProcessor = postLoadProcessor;
	}

	/**
	* The post load model processor.
	*
	* @since 1.3
	*/
	public IResourceSetProcessor getPostLoadModelProcessor() {
	return postLoadProcessor;
	}
	}