bundles/org.eclipse.equinox.p2.ui.sdk.scheduler/src/org/eclipse/equinox/internal/p2/ui/sdk/scheduler/migration/MigrationSupport.java - equinox/rt.equinox.p2 - Git at Google

 /*******************************************************************************
  * Copyright (c) 2013, 2015 Ericsson AB 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:
  *     Ericsson AB - initial API and implementation
  *     Ericsson AB (Pascal Rapicault)
  *     Ericsson AB (Hamdan Msheik)
  *     Red Hat Inc. - Bug 460967
  ******************************************************************************/
 package org.eclipse.equinox.internal.p2.ui.sdk.scheduler.migration;

 import java.io.File;
 import java.net.URI;
 import java.util.*;
 import org.eclipse.core.runtime.URIUtil;
 import org.eclipse.equinox.internal.p2.core.helpers.ServiceHelper;
 import org.eclipse.equinox.internal.p2.engine.EngineActivator;
 import org.eclipse.equinox.internal.p2.metadata.query.UpdateQuery;
 import org.eclipse.equinox.internal.p2.ui.sdk.scheduler.*;
 import org.eclipse.equinox.p2.core.IAgentLocation;
 import org.eclipse.equinox.p2.core.IProvisioningAgent;
 import org.eclipse.equinox.p2.engine.IProfile;
 import org.eclipse.equinox.p2.engine.IProfileRegistry;
 import org.eclipse.equinox.p2.engine.query.IUProfilePropertyQuery;
 import org.eclipse.equinox.p2.engine.query.UserVisibleRootQuery;
 import org.eclipse.equinox.p2.metadata.IInstallableUnit;
 import org.eclipse.equinox.p2.query.IQueryResult;
 import org.eclipse.equinox.p2.query.QueryUtil;
 import org.eclipse.equinox.p2.repository.IRepositoryManager;
 import org.eclipse.equinox.p2.repository.metadata.IMetadataRepositoryManager;
 import org.eclipse.equinox.p2.ui.ProvisioningUI;
 import org.eclipse.jface.wizard.WizardDialog;
 import org.eclipse.osgi.service.datalocation.Location;
 import org.eclipse.swt.widgets.Display;
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.ui.IWorkbenchWindow;
 import org.eclipse.ui.PlatformUI;

 public class MigrationSupport {
 	private static final String ECLIPSE_P2_SKIP_MIGRATION_WIZARD = "eclipse.p2.skipMigrationWizard"; //$NON-NLS-1$
 	private static final String ECLIPSE_P2_SKIP_MOVED_INSTALL_DETECTION = "eclipse.p2.skipMovedInstallDetection"; //$NON-NLS-1$

 	//The return value indicates if the migration dialog has been shown or not. It does not indicate whether the migration has completed.
 	public boolean performMigration(IProvisioningAgent agent, IProfileRegistry registry, IProfile currentProfile) {
 		boolean skipWizard = Boolean.TRUE.toString().equalsIgnoreCase(System.getProperty(ECLIPSE_P2_SKIP_MIGRATION_WIZARD));
 		if (skipWizard)
 			return false;

 		IProfile previousProfile = null;
 		URI[] reposToMigrate = null;
 		if (!skipFirstTimeMigration() && !configurationSpecifiedManually() && isFirstTimeRunningThisSharedInstance(agent, registry, currentProfile)) {
 			File searchRoot = getSearchLocation();
 			if (searchRoot == null)
 				return false;

 			IProvisioningAgent otherConfigAgent = new PreviousConfigurationFinder(getConfigurationLocation().getParentFile()).findPreviousInstalls(searchRoot, getInstallFolder());
 			if (otherConfigAgent == null) {
 				return false;
 			}
 			previousProfile = ((IProfileRegistry) otherConfigAgent.getService(IProfileRegistry.SERVICE_NAME)).getProfile(IProfileRegistry.SELF);
 			if (previousProfile == null)
 				return false;

 			reposToMigrate = ((IMetadataRepositoryManager) otherConfigAgent.getService(IMetadataRepositoryManager.SERVICE_NAME)).getKnownRepositories(IRepositoryManager.REPOSITORIES_NON_SYSTEM);
 			reposToMigrate = copyOf(reposToMigrate, reposToMigrate.length + 1);
 			reposToMigrate[reposToMigrate.length - 1] = getURIForProfile(otherConfigAgent, previousProfile);
 		}

 		if (previousProfile == null && baseChangedSinceLastPresentationOfWizard(agent, registry, currentProfile))
 			previousProfile = findMostRecentReset(registry, currentProfile);

 		if (previousProfile == null)
 			return false;

 		Collection<IInstallableUnit> unitsToMigrate = findUnitstoMigrate(previousProfile, currentProfile);
 		if (!unitsToMigrate.isEmpty()) {
 			openMigrationWizard(previousProfile, unitsToMigrate, reposToMigrate);
 		} else {
 			//There is nothing to migrate, so we mark the migration complete
 			rememberMigrationCompleted();
 		}
 		return true;
 	}

 	private static URI[] copyOf(URI[] original, int newLength) {
 		URI[] copy = new URI[newLength];
 		int copyCount = Math.min(original.length, newLength);
 		System.arraycopy(original, 0, copy, 0, copyCount);
 		return copy;
 	}

 	private URI getURIForProfile(IProvisioningAgent agent, IProfile profile) {
 		IAgentLocation agentLocation = (IAgentLocation) agent.getService(IAgentLocation.SERVICE_NAME);
 		return URIUtil.append(agentLocation.getRootLocation(), "org.eclipse.equinox.p2.engine/profileRegistry/" + profile.getProfileId() + ".profile"); //$NON-NLS-1$ //$NON-NLS-2$
 	}

 	private File getInstallFolder() {
 		Location configurationLocation = ServiceHelper.getService(EngineActivator.getContext(), Location.class, Location.INSTALL_FILTER);
 		return new File(configurationLocation.getURL().getPath());
 	}

 	//The search location is two level up from the configuration location.
 	private File getSearchLocation() {
 		File parent = getConfigurationLocation().getParentFile();
 		if (parent == null)
 			return null;
 		return parent.getParentFile();
 	}

 	private File getConfigurationLocation() {
 		Location configurationLocation = ServiceHelper.getService(EngineActivator.getContext(), Location.class, Location.CONFIGURATION_FILTER);
 		File configurationFolder = new File(configurationLocation.getURL().getPath());
 		return configurationFolder;
 	}

 	//Check if the user has explicitly specified -configuration on the command line
 	private boolean configurationSpecifiedManually() {
 		String commandLine = System.getProperty("eclipse.commands"); //$NON-NLS-1$
 		if (commandLine == null)
 			return false;
 		return commandLine.contains("-configuration\n"); //$NON-NLS-1$
 	}

 	private boolean skipFirstTimeMigration() {
 		return Boolean.TRUE.toString().equalsIgnoreCase(System.getProperty(ECLIPSE_P2_SKIP_MOVED_INSTALL_DETECTION));
 	}

 	private boolean isFirstTimeRunningThisSharedInstance(IProvisioningAgent agent, IProfileRegistry registry, IProfile currentProfile) {
 		long[] history = registry.listProfileTimestamps(currentProfile.getProfileId());
 		boolean isInitial = IProfile.STATE_SHARED_INSTALL_VALUE_INITIAL.equals(registry.getProfileStateProperties(currentProfile.getProfileId(), history[0]).get(IProfile.STATE_PROP_SHARED_INSTALL));
 		if (isInitial) {
 			if (getLastMigration() >= history[0])
 				return false;
 			//This detect the case where the user has not done any migration.
 			Map<String, String> sharedRelatedValues = registry.getProfileStateProperties(currentProfile.getProfileId(), IProfile.STATE_PROP_SHARED_INSTALL);
 			if (sharedRelatedValues.containsValue(IProfile.STATE_SHARED_INSTALL_VALUE_NEW))
 				return false;
 			return true;
 		}
 		return false;
 	}

 	/**
 	 * @param previousProfile is the profile used previous to the current one
 	 * @param currentProfile is the current profile used by eclipse.
 	 * @return true if set difference between previousProfile units and currentProfile units not empty, otherwise false
 	 */
 	protected Collection<IInstallableUnit> findUnitstoMigrate(IProfile previousProfile, IProfile currentProfile) {
 		//First, try the case of inclusion
 		Set<IInstallableUnit> previousProfileUnits = getUserRoots(previousProfile);
 		Set<IInstallableUnit> currentProfileUnits = currentProfile.available(new UserVisibleRootQuery(), null).toSet();
 		previousProfileUnits.removeAll(currentProfileUnits);

 		//For the IUs left in the previous profile, look for those that could be in the base but not as roots
 		Iterator<IInstallableUnit> previousProfileIterator = previousProfileUnits.iterator();
 		while (previousProfileIterator.hasNext()) {
 			if (!currentProfile.available(QueryUtil.createIUQuery(previousProfileIterator.next()), null).isEmpty())
 				previousProfileIterator.remove();
 		}

 		//For the IUs left in the previous profile, look for those that could be available in the root but as higher versions (they could be root or not)
 		previousProfileIterator = previousProfileUnits.iterator();
 		while (previousProfileIterator.hasNext()) {
 			if (!currentProfile.available(new UpdateQuery(previousProfileIterator.next()), null).isEmpty())
 				previousProfileIterator.remove();
 		}

 		return previousProfileUnits;
 	}

 	private Set<IInstallableUnit> getUserRoots(IProfile previousProfile) {
 		IQueryResult<IInstallableUnit> allRoots = previousProfile.query(new UserVisibleRootQuery(), null);
 		Set<IInstallableUnit> rootsFromTheBase = previousProfile.query(new IUProfilePropertyQuery("org.eclipse.equinox.p2.base", "true"), null).toUnmodifiableSet();
 		Set<IInstallableUnit> userRoots = allRoots.toSet();
 		userRoots.removeAll(rootsFromTheBase);
 		return userRoots;
 	}

 	protected void openMigrationWizard(final IProfile inputProfile, final Collection<IInstallableUnit> unitsToMigrate, final URI[] reposToMigrate) {
 		Display d = Display.getDefault();
 		d.asyncExec(new Runnable() {
 			public void run() {
 				WizardDialog migrateWizard = new MigrationWizardDialog(getWorkbenchWindowShell(), new MigrationWizard(inputProfile, unitsToMigrate, reposToMigrate, reposToMigrate != null));
 				migrateWizard.create();
 				migrateWizard.open();
 			}
 		});
 	}

 	private boolean baseChangedSinceLastPresentationOfWizard(IProvisioningAgent agent, IProfileRegistry registry, IProfile profile) {
 		long lastProfileMigrated = getLastMigration();
 		long lastResetTimestamp = findMostRecentResetTimestamp(registry, profile);
 		return lastProfileMigrated <= lastResetTimestamp;
 	}

 	//The timestamp from which we migrated or -1
 	private long findMostRecentResetTimestamp(IProfileRegistry registry, IProfile profile) {
 		long[] history = registry.listProfileTimestamps(profile.getProfileId());
 		int index = history.length - 1;
 		boolean found = false;
 		while (!(found = IProfile.STATE_SHARED_INSTALL_VALUE_BEFOREFLUSH.equals(registry.getProfileStateProperties(profile.getProfileId(), history[index]).get(IProfile.STATE_PROP_SHARED_INSTALL))) && index > 0) {
 			index--;
 		}
 		if (!found)
 			return -1;
 		return history[index];
 	}

 	private IProfile findMostRecentReset(IProfileRegistry registry, IProfile profile) {
 		long ts = findMostRecentResetTimestamp(registry, profile);
 		if (ts == -1)
 			return null;
 		return registry.getProfile(profile.getProfileId(), ts);
 	}

 	Shell getWorkbenchWindowShell() {
 		IWorkbenchWindow activeWindow = PlatformUI.getWorkbench().getActiveWorkbenchWindow();
 		return activeWindow != null ? activeWindow.getShell() : null;
 	}

 	public void rememberMigrationCompleted() {
 		IProfileRegistry registry = (IProfileRegistry) ProvisioningUI.getDefaultUI().getSession().getProvisioningAgent().getService(IProfileRegistry.SERVICE_NAME);
 		long[] history = registry.listProfileTimestamps(ProvisioningUI.getDefaultUI().getProfileId());
 		AutomaticUpdatePlugin.getDefault().getPreferenceStore().setValue(AutomaticUpdateScheduler.MIGRATION_DIALOG_SHOWN, history[history.length - 1]);
 		AutomaticUpdatePlugin.getDefault().savePreferences();
 	}

 	//Get the timestamp that we migrated from. O if we have not migrated.
 	public long getLastMigration() {
 		return AutomaticUpdatePlugin.getDefault().getPreferenceStore().getLong(AutomaticUpdateScheduler.MIGRATION_DIALOG_SHOWN);
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2013, 2015 Ericsson AB 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:
	* Ericsson AB - initial API and implementation
	* Ericsson AB (Pascal Rapicault)
	* Ericsson AB (Hamdan Msheik)
	* Red Hat Inc. - Bug 460967
	******************************************************************************/
	package org.eclipse.equinox.internal.p2.ui.sdk.scheduler.migration;

	import java.io.File;
	import java.net.URI;
	import java.util.*;
	import org.eclipse.core.runtime.URIUtil;
	import org.eclipse.equinox.internal.p2.core.helpers.ServiceHelper;
	import org.eclipse.equinox.internal.p2.engine.EngineActivator;
	import org.eclipse.equinox.internal.p2.metadata.query.UpdateQuery;
	import org.eclipse.equinox.internal.p2.ui.sdk.scheduler.*;
	import org.eclipse.equinox.p2.core.IAgentLocation;
	import org.eclipse.equinox.p2.core.IProvisioningAgent;
	import org.eclipse.equinox.p2.engine.IProfile;
	import org.eclipse.equinox.p2.engine.IProfileRegistry;
	import org.eclipse.equinox.p2.engine.query.IUProfilePropertyQuery;
	import org.eclipse.equinox.p2.engine.query.UserVisibleRootQuery;
	import org.eclipse.equinox.p2.metadata.IInstallableUnit;
	import org.eclipse.equinox.p2.query.IQueryResult;
	import org.eclipse.equinox.p2.query.QueryUtil;
	import org.eclipse.equinox.p2.repository.IRepositoryManager;
	import org.eclipse.equinox.p2.repository.metadata.IMetadataRepositoryManager;
	import org.eclipse.equinox.p2.ui.ProvisioningUI;
	import org.eclipse.jface.wizard.WizardDialog;
	import org.eclipse.osgi.service.datalocation.Location;
	import org.eclipse.swt.widgets.Display;
	import org.eclipse.swt.widgets.Shell;
	import org.eclipse.ui.IWorkbenchWindow;
	import org.eclipse.ui.PlatformUI;

	public class MigrationSupport {
	private static final String ECLIPSE_P2_SKIP_MIGRATION_WIZARD = "eclipse.p2.skipMigrationWizard"; //$NON-NLS-1$
	private static final String ECLIPSE_P2_SKIP_MOVED_INSTALL_DETECTION = "eclipse.p2.skipMovedInstallDetection"; //$NON-NLS-1$

	//The return value indicates if the migration dialog has been shown or not. It does not indicate whether the migration has completed.
	public boolean performMigration(IProvisioningAgent agent, IProfileRegistry registry, IProfile currentProfile) {
	boolean skipWizard = Boolean.TRUE.toString().equalsIgnoreCase(System.getProperty(ECLIPSE_P2_SKIP_MIGRATION_WIZARD));
	if (skipWizard)
	return false;

	IProfile previousProfile = null;
	URI[] reposToMigrate = null;
	if (!skipFirstTimeMigration() && !configurationSpecifiedManually() && isFirstTimeRunningThisSharedInstance(agent, registry, currentProfile)) {
	File searchRoot = getSearchLocation();
	if (searchRoot == null)
	return false;

	IProvisioningAgent otherConfigAgent = new PreviousConfigurationFinder(getConfigurationLocation().getParentFile()).findPreviousInstalls(searchRoot, getInstallFolder());
	if (otherConfigAgent == null) {
	return false;
	}
	previousProfile = ((IProfileRegistry) otherConfigAgent.getService(IProfileRegistry.SERVICE_NAME)).getProfile(IProfileRegistry.SELF);
	if (previousProfile == null)
	return false;

	reposToMigrate = ((IMetadataRepositoryManager) otherConfigAgent.getService(IMetadataRepositoryManager.SERVICE_NAME)).getKnownRepositories(IRepositoryManager.REPOSITORIES_NON_SYSTEM);
	reposToMigrate = copyOf(reposToMigrate, reposToMigrate.length + 1);
	reposToMigrate[reposToMigrate.length - 1] = getURIForProfile(otherConfigAgent, previousProfile);
	}

	if (previousProfile == null && baseChangedSinceLastPresentationOfWizard(agent, registry, currentProfile))
	previousProfile = findMostRecentReset(registry, currentProfile);

	if (previousProfile == null)
	return false;

	Collection<IInstallableUnit> unitsToMigrate = findUnitstoMigrate(previousProfile, currentProfile);
	if (!unitsToMigrate.isEmpty()) {
	openMigrationWizard(previousProfile, unitsToMigrate, reposToMigrate);
	} else {
	//There is nothing to migrate, so we mark the migration complete
	rememberMigrationCompleted();
	}
	return true;
	}

	private static URI[] copyOf(URI[] original, int newLength) {
	URI[] copy = new URI[newLength];
	int copyCount = Math.min(original.length, newLength);
	System.arraycopy(original, 0, copy, 0, copyCount);
	return copy;
	}

	private URI getURIForProfile(IProvisioningAgent agent, IProfile profile) {
	IAgentLocation agentLocation = (IAgentLocation) agent.getService(IAgentLocation.SERVICE_NAME);
	return URIUtil.append(agentLocation.getRootLocation(), "org.eclipse.equinox.p2.engine/profileRegistry/" + profile.getProfileId() + ".profile"); //$NON-NLS-1$ //$NON-NLS-2$
	}

	private File getInstallFolder() {
	Location configurationLocation = ServiceHelper.getService(EngineActivator.getContext(), Location.class, Location.INSTALL_FILTER);
	return new File(configurationLocation.getURL().getPath());
	}

	//The search location is two level up from the configuration location.
	private File getSearchLocation() {
	File parent = getConfigurationLocation().getParentFile();
	if (parent == null)
	return null;
	return parent.getParentFile();
	}

	private File getConfigurationLocation() {
	Location configurationLocation = ServiceHelper.getService(EngineActivator.getContext(), Location.class, Location.CONFIGURATION_FILTER);
	File configurationFolder = new File(configurationLocation.getURL().getPath());
	return configurationFolder;
	}

	//Check if the user has explicitly specified -configuration on the command line
	private boolean configurationSpecifiedManually() {
	String commandLine = System.getProperty("eclipse.commands"); //$NON-NLS-1$
	if (commandLine == null)
	return false;
	return commandLine.contains("-configuration\n"); //$NON-NLS-1$
	}

	private boolean skipFirstTimeMigration() {
	return Boolean.TRUE.toString().equalsIgnoreCase(System.getProperty(ECLIPSE_P2_SKIP_MOVED_INSTALL_DETECTION));
	}

	private boolean isFirstTimeRunningThisSharedInstance(IProvisioningAgent agent, IProfileRegistry registry, IProfile currentProfile) {
	long[] history = registry.listProfileTimestamps(currentProfile.getProfileId());
	boolean isInitial = IProfile.STATE_SHARED_INSTALL_VALUE_INITIAL.equals(registry.getProfileStateProperties(currentProfile.getProfileId(), history[0]).get(IProfile.STATE_PROP_SHARED_INSTALL));
	if (isInitial) {
	if (getLastMigration() >= history[0])
	return false;
	//This detect the case where the user has not done any migration.
	Map<String, String> sharedRelatedValues = registry.getProfileStateProperties(currentProfile.getProfileId(), IProfile.STATE_PROP_SHARED_INSTALL);
	if (sharedRelatedValues.containsValue(IProfile.STATE_SHARED_INSTALL_VALUE_NEW))
	return false;
	return true;
	}
	return false;
	}

	/**
	* @param previousProfile is the profile used previous to the current one
	* @param currentProfile is the current profile used by eclipse.
	* @return true if set difference between previousProfile units and currentProfile units not empty, otherwise false
	*/
	protected Collection<IInstallableUnit> findUnitstoMigrate(IProfile previousProfile, IProfile currentProfile) {
	//First, try the case of inclusion
	Set<IInstallableUnit> previousProfileUnits = getUserRoots(previousProfile);
	Set<IInstallableUnit> currentProfileUnits = currentProfile.available(new UserVisibleRootQuery(), null).toSet();
	previousProfileUnits.removeAll(currentProfileUnits);

	//For the IUs left in the previous profile, look for those that could be in the base but not as roots
	Iterator<IInstallableUnit> previousProfileIterator = previousProfileUnits.iterator();
	while (previousProfileIterator.hasNext()) {
	if (!currentProfile.available(QueryUtil.createIUQuery(previousProfileIterator.next()), null).isEmpty())
	previousProfileIterator.remove();
	}

	//For the IUs left in the previous profile, look for those that could be available in the root but as higher versions (they could be root or not)
	previousProfileIterator = previousProfileUnits.iterator();
	while (previousProfileIterator.hasNext()) {
	if (!currentProfile.available(new UpdateQuery(previousProfileIterator.next()), null).isEmpty())
	previousProfileIterator.remove();
	}

	return previousProfileUnits;
	}

	private Set<IInstallableUnit> getUserRoots(IProfile previousProfile) {
	IQueryResult<IInstallableUnit> allRoots = previousProfile.query(new UserVisibleRootQuery(), null);
	Set<IInstallableUnit> rootsFromTheBase = previousProfile.query(new IUProfilePropertyQuery("org.eclipse.equinox.p2.base", "true"), null).toUnmodifiableSet();
	Set<IInstallableUnit> userRoots = allRoots.toSet();
	userRoots.removeAll(rootsFromTheBase);
	return userRoots;
	}

	protected void openMigrationWizard(final IProfile inputProfile, final Collection<IInstallableUnit> unitsToMigrate, final URI[] reposToMigrate) {
	Display d = Display.getDefault();
	d.asyncExec(new Runnable() {
	public void run() {
	WizardDialog migrateWizard = new MigrationWizardDialog(getWorkbenchWindowShell(), new MigrationWizard(inputProfile, unitsToMigrate, reposToMigrate, reposToMigrate != null));
	migrateWizard.create();
	migrateWizard.open();
	}
	});
	}

	private boolean baseChangedSinceLastPresentationOfWizard(IProvisioningAgent agent, IProfileRegistry registry, IProfile profile) {
	long lastProfileMigrated = getLastMigration();
	long lastResetTimestamp = findMostRecentResetTimestamp(registry, profile);
	return lastProfileMigrated <= lastResetTimestamp;
	}

	//The timestamp from which we migrated or -1
	private long findMostRecentResetTimestamp(IProfileRegistry registry, IProfile profile) {
	long[] history = registry.listProfileTimestamps(profile.getProfileId());
	int index = history.length - 1;
	boolean found = false;
	while (!(found = IProfile.STATE_SHARED_INSTALL_VALUE_BEFOREFLUSH.equals(registry.getProfileStateProperties(profile.getProfileId(), history[index]).get(IProfile.STATE_PROP_SHARED_INSTALL))) && index > 0) {
	index--;
	}
	if (!found)
	return -1;
	return history[index];
	}

	private IProfile findMostRecentReset(IProfileRegistry registry, IProfile profile) {
	long ts = findMostRecentResetTimestamp(registry, profile);
	if (ts == -1)
	return null;
	return registry.getProfile(profile.getProfileId(), ts);
	}

	Shell getWorkbenchWindowShell() {
	IWorkbenchWindow activeWindow = PlatformUI.getWorkbench().getActiveWorkbenchWindow();
	return activeWindow != null ? activeWindow.getShell() : null;
	}

	public void rememberMigrationCompleted() {
	IProfileRegistry registry = (IProfileRegistry) ProvisioningUI.getDefaultUI().getSession().getProvisioningAgent().getService(IProfileRegistry.SERVICE_NAME);
	long[] history = registry.listProfileTimestamps(ProvisioningUI.getDefaultUI().getProfileId());
	AutomaticUpdatePlugin.getDefault().getPreferenceStore().setValue(AutomaticUpdateScheduler.MIGRATION_DIALOG_SHOWN, history[history.length - 1]);
	AutomaticUpdatePlugin.getDefault().savePreferences();
	}

	//Get the timestamp that we migrated from. O if we have not migrated.
	public long getLastMigration() {
	return AutomaticUpdatePlugin.getDefault().getPreferenceStore().getLong(AutomaticUpdateScheduler.MIGRATION_DIALOG_SHOWN);
	}
	}