update/org.eclipse.update.ui/src/org/eclipse/update/internal/ui/wizards/InstallWizard.java - platform/eclipse.platform - Git at Google

 package org.eclipse.update.internal.ui.wizards;
 /*
  * (c) Copyright IBM Corp. 2000, 2001.
  * All Rights Reserved.
  */
 import java.lang.reflect.InvocationTargetException;
 import java.net.URL;
 import java.text.DateFormat;
 import java.util.ArrayList;

 import org.eclipse.core.runtime.*;
 import org.eclipse.jface.operation.IRunnableWithProgress;
 import org.eclipse.jface.wizard.IWizardPage;
 import org.eclipse.jface.wizard.Wizard;
 import org.eclipse.update.configuration.*;
 import org.eclipse.update.core.*;
 import org.eclipse.update.core.model.InstallAbortedException;
 import org.eclipse.update.internal.ui.*;
 import org.eclipse.update.internal.ui.UpdateUIPlugin;
 import org.eclipse.update.internal.ui.UpdateUIPluginImages;
 import org.eclipse.update.internal.ui.model.PendingChange;
 import org.eclipse.update.internal.ui.model.UpdateModel;
 import org.eclipse.update.internal.ui.security.JarVerificationService;

 public class InstallWizard extends Wizard {
 	private static final String KEY_UNABLE = "InstallWizard.error.unable";
 	private static final String KEY_OLD = "InstallWizard.error.old";
 	private static final String KEY_SAVED_CONFIG = "InstallWizard.savedConfig";
 	private ReviewPage reviewPage;
 	private OptionalFeaturesPage optionalFeaturesPage;
 	private TargetPage targetPage;
 	private PendingChange job;
 	private boolean successfulInstall = false;
 	private IInstallConfiguration config;
 	private boolean patch;

 	public InstallWizard(PendingChange job) {
 		setDialogSettings(UpdateUIPlugin.getDefault().getDialogSettings());
 		setDefaultPageImageDescriptor(UpdateUIPluginImages.DESC_INSTALL_WIZ);
 		setForcePreviousAndNextButtons(true);
 		setNeedsProgressMonitor(true);
 		this.job = job;
 		IFeature feature = job.getFeature();
 		patch = UpdateUIPlugin.isPatch(feature);
 	}

 	public boolean isSuccessfulInstall() {
 		return successfulInstall;
 	}

 	/**
 	 * @see Wizard#performFinish()
 	 */
 	public boolean performFinish() {
 		final IConfiguredSite targetSite =
 			(targetPage == null) ? null : targetPage.getTargetSite();
 		final IFeatureReference[] optionalFeatures =
 			(optionalFeaturesPage == null)
 				? null
 				: optionalFeaturesPage.getCheckedOptionalFeatures();
 		final Object[] optionalElements =
 			(optionalFeaturesPage == null)
 				? null
 				: optionalFeaturesPage.getOptionalElements();
 		if (job.getJobType() == PendingChange.INSTALL) {
 			ArrayList conflicts =
 				DuplicateConflictsDialog.computeDuplicateConflicts(
 					job,
 					config,
 					targetSite,
 					optionalFeatures);
 			if (conflicts != null) {
 				DuplicateConflictsDialog dialog =
 					new DuplicateConflictsDialog(getShell(), conflicts);
 				if (dialog.open() != 0)
 					return false;
 			}
 		}
 		IRunnableWithProgress operation = new IRunnableWithProgress() {
 			public void run(IProgressMonitor monitor)
 				throws InvocationTargetException {
 				try {
 					successfulInstall = false;
 					makeConfigurationCurrent(config, job);
 					execute(
 						targetSite,
 						optionalElements,
 						optionalFeatures,
 						monitor);
 					saveLocalSite();
 					successfulInstall = true;
 				} catch (CoreException e) {
 					throw new InvocationTargetException(e);
 				} finally {
 					monitor.done();
 				}
 			}
 		};
 		try {
 			getContainer().run(true, true, operation);
 		} catch (InvocationTargetException e) {
 			Throwable target = e.getTargetException();
 			if (target instanceof InstallAbortedException) {
 				// should we revert to the previous configuration?
 			} else {
 				UpdateUIPlugin.logException(e);
 			}
 			return false;
 		} catch (InterruptedException e) {
 			return false;
 		}
 		return true;
 	}

 	public void addPages() {
 		reviewPage = new ReviewPage(job);
 		addPage(reviewPage);

 		config = createInstallConfiguration();

 		if (job.getJobType() == PendingChange.INSTALL) {
 			if (UpdateModel.hasLicense(job)) {
 				addPage(new LicensePage(job));
 			}
 			if (hasOptionalFeatures(job.getFeature())) {
 				optionalFeaturesPage = new OptionalFeaturesPage(job, config);
 				addPage(optionalFeaturesPage);
 			}
 			targetPage = new TargetPage(job, config);
 			addPage(targetPage);
 		}
 	}

 	public static IInstallConfiguration createInstallConfiguration() {
 		try {
 			ILocalSite localSite = SiteManager.getLocalSite();
 			IInstallConfiguration config =
 				localSite.cloneCurrentConfiguration();
 			config.setLabel(Utilities.format(config.getCreationDate()));
 			return config;
 		} catch (CoreException e) {
 			UpdateUIPlugin.logException(e);
 			return null;
 		}
 	}

 	public static void makeConfigurationCurrent(IInstallConfiguration config, PendingChange job)
 		throws CoreException {
 		ILocalSite localSite = SiteManager.getLocalSite();
 		if (job!=null && job.getJobType()==PendingChange.INSTALL) {
 			if (UpdateUIPlugin.isPatch(job.getFeature())) {
 				// Installing a patch - preserve the current configuration
 				IInstallConfiguration cconfig = localSite.getCurrentConfiguration();
 				IInstallConfiguration savedConfig = localSite.addToPreservedConfigurations(cconfig);
 				VersionedIdentifier vid = job.getFeature().getVersionedIdentifier();
 				String key = "@"+vid.getIdentifier()+"_"+vid.getVersion();
 				String newLabel = UpdateUIPlugin.getFormattedMessage(KEY_SAVED_CONFIG, key);
 				savedConfig.setLabel(newLabel);
 				UpdateModel model = UpdateUIPlugin.getDefault().getUpdateModel();
 				model.fireObjectChanged(savedConfig, null);
 			}
 		}
 		localSite.addConfiguration(config);
 	}

 	public static void saveLocalSite() throws CoreException {
 		ILocalSite localSite = SiteManager.getLocalSite();
 		localSite.save();
 	}

 	public boolean canFinish() {
 		IWizardPage page = getContainer().getCurrentPage();
 		return page.getNextPage() == null && super.canFinish();
 	}

 	public IWizardPage getPreviousPage(IWizardPage page) {
 		return super.getPreviousPage(page);
 	}
 	public IWizardPage getNextPage(IWizardPage page) {
 		return super.getNextPage(page);
 	}
 	/*
 	 * When we are uninstalling, there is no targetSite
 	 */
 	private void execute(
 		IConfiguredSite targetSite,
 		Object[] optionalElements,
 		IFeatureReference[] optionalFeatures,
 		IProgressMonitor monitor)
 		throws CoreException {
 		IFeature feature = job.getFeature();
 		if (job.getJobType() == PendingChange.UNINSTALL) {
 			//find the  config site of this feature
 			IConfiguredSite site = findConfigSite(feature, config);
 			if (site != null) {
 				site.remove(feature, monitor);
 			} else {
 				// we should do something here
 				throwError(UpdateUIPlugin.getResourceString(KEY_UNABLE));
 			}
 		} else if (job.getJobType() == PendingChange.INSTALL) {
 			if (optionalFeatures == null)
 				targetSite.install(feature, getVerificationListener(), monitor);
 			else
 				targetSite.install(
 					feature,
 					optionalFeatures,
 					getVerificationListener(),
 					monitor);
 			IFeature oldFeature = job.getOldFeature();
 			if (oldFeature != null && !job.isOptionalDelta()) {
 				if (optionalElements != null) {
 					boolean patch = UpdateUIPlugin.isPatch(feature);
 					preserveOptionalState(config, targetSite, patch, optionalElements);
 				}
 				boolean oldSuccess = unconfigure(config, oldFeature);
 				if (!oldSuccess) {
 					if (!isNestedChild(oldFeature))
 						// "eat" the error if nested child
 						throwError(UpdateUIPlugin.getResourceString(KEY_OLD));
 				}
 			}
 			if (oldFeature == null) {
 				ensureUnique(config, feature, targetSite);
 				if (optionalFeatures != null) {
 					preserveOriginatingURLs(feature, optionalFeatures);
 				}
 			}
 		} else if (job.getJobType() == PendingChange.CONFIGURE) {
 			configure(feature);
 			ensureUnique(config, feature, targetSite);
 		} else if (job.getJobType() == PendingChange.UNCONFIGURE) {
 			unconfigure(config, job.getFeature());
 		} else {
 			// should not be here
 			return;
 		}
 		UpdateModel model = UpdateUIPlugin.getDefault().getUpdateModel();
 		model.addPendingChange(job);
 	}

 	static void ensureUnique(
 		IInstallConfiguration config,
 		IFeature feature,
 		IConfiguredSite targetSite)
 		throws CoreException {
 		boolean patch = false;
 		if (targetSite==null)
 			targetSite = feature.getSite().getCurrentConfiguredSite();
 		IImport[] imports = feature.getImports();
 		for (int i = 0; i < imports.length; i++) {
 			IImport iimport = imports[i];
 			if (iimport.isPatch()) {
 				patch = true;
 				break;
 			}
 		}
 		// Only need to check features that patch other features.
 		if (!patch)
 			return;
 		IFeature localFeature = findLocalFeature(targetSite, feature);
 		ArrayList oldFeatures = new ArrayList();
 		// First collect all older active features that
 		// have the same ID as new features marked as 'unique'.
 		collectOldFeatures(localFeature, targetSite, oldFeatures);
 		// Now unconfigure old features to enforce uniqueness
 		for (int i = 0; i < oldFeatures.size(); i++) {
 			IFeature oldFeature = (IFeature) oldFeatures.get(i);
 			unconfigure(config, oldFeature);
 		}
 	}

 	private void throwError(String message) throws CoreException {
 		IStatus status =
 			new Status(
 				IStatus.ERROR,
 				UpdateUIPlugin.getPluginId(),
 				IStatus.OK,
 				message,
 				null);
 		throw new CoreException(status);
 	}

 	static IConfiguredSite findConfigSite(
 		IFeature feature,
 		IInstallConfiguration config)
 		throws CoreException {
 		IConfiguredSite[] configSites = config.getConfiguredSites();
 		for (int i = 0; i < configSites.length; i++) {
 			IConfiguredSite site = configSites[i];
 			if (site.getSite().equals(feature.getSite())) {
 				return site;
 			}
 		}
 		return null;
 	}

 	private static boolean unconfigure(
 		IInstallConfiguration config,
 		IFeature feature)
 		throws CoreException {
 		IConfiguredSite site = findConfigSite(feature, config);
 		if (site != null) {
 			PatchCleaner cleaner = new PatchCleaner(site, feature);
 			boolean result = site.unconfigure(feature);
 			cleaner.dispose();
 			return result;
 		}
 		return false;
 	}

 	private void configure(IFeature feature) throws CoreException {
 		IConfiguredSite site = findConfigSite(feature, config);
 		if (site != null) {
 			site.configure(feature);
 		}
 	}

 	private IVerificationListener getVerificationListener() {
 		return new JarVerificationService(this.getShell());
 	}

 	private boolean isNestedChild(IFeature feature) {
 		IConfiguredSite[] csites = config.getConfiguredSites();
 		try {
 			for (int i = 0; csites != null && i < csites.length; i++) {
 				IFeatureReference[] refs = csites[i].getConfiguredFeatures();
 				for (int j = 0; refs != null && j < refs.length; j++) {
 					IFeature parent = refs[j].getFeature();
 					IFeatureReference[] children =
 						parent.getIncludedFeatureReferences();
 					for (int k = 0;
 						children != null && k < children.length;
 						k++) {
 						IFeature child = children[k].getFeature();
 						if (feature.equals(child))
 							return true;
 					}
 				}
 			}
 		} catch (CoreException e) {
 			// will return false
 		}
 		return false;
 	}

 	static boolean hasOptionalFeatures(IFeatureReference fref) {
 		try {
 			return hasOptionalFeatures(fref.getFeature());
 		} catch (CoreException e) {
 			return false;
 		}
 	}
 	static boolean hasOptionalFeatures(IFeature feature) {
 		try {
 			IFeatureReference[] irefs = feature.getIncludedFeatureReferences();
 			for (int i = 0; i < irefs.length; i++) {
 				IFeatureReference iref = irefs[i];
 				if (iref.isOptional())
 					return true;
 				// see if it has optional children
 				IFeature child = iref.getFeature();
 				if (hasOptionalFeatures(child))
 					return true;
 			}
 		} catch (CoreException e) {
 		}
 		return false;
 	}

 	static void preserveOptionalState(
 		IInstallConfiguration config,
 		IConfiguredSite targetSite,
 		boolean patch,
 		Object[] optionalElements) {
 		for (int i = 0; i < optionalElements.length; i++) {
 			FeatureHierarchyElement fe =
 				(FeatureHierarchyElement) optionalElements[i];
 			Object[] children = fe.getChildren(true, patch, config);
 			preserveOptionalState(config, targetSite, patch, children);
 			if (!fe.isEnabled(config)) {
 				IFeature newFeature = fe.getFeature();
 				try {
 					IFeature localFeature =
 						findLocalFeature(targetSite, newFeature);
 					if (localFeature != null)
 						targetSite.unconfigure(localFeature);
 				} catch (CoreException e) {
 					// Eat this - we will leave with it
 				}
 			}
 		}
 	}

 	static void collectOldFeatures(
 		IFeature feature,
 		IConfiguredSite targetSite,
 		ArrayList result)
 		throws CoreException {
 		IFeatureReference[] included = feature.getIncludedFeatureReferences();
 		for (int i = 0; i < included.length; i++) {
 			IFeatureReference iref = included[i];
 			IFeature ifeature;

 			try {
 				ifeature = iref.getFeature();
 			}
 			catch (CoreException e) {
 				if (iref.isOptional())
 					continue;
 				throw e;
 			}
 			// find other features and unconfigure
 			String id = iref.getVersionedIdentifier().getIdentifier();
 			IFeature[] sameIds =
 				UpdateUIPlugin.searchSite(id, targetSite, true);
 			for (int j = 0; j < sameIds.length; j++) {
 				IFeature sameId = sameIds[j];
 				// Ignore self.
 				if (sameId.equals(ifeature))
 					continue;
 				result.add(sameId);
 			}
 			collectOldFeatures(ifeature, targetSite, result);
 		}
 	}

 	private static IFeature findLocalFeature(
 		IConfiguredSite csite,
 		IFeature feature)
 		throws CoreException {
 		IFeatureReference[] refs = csite.getConfiguredFeatures();
 		for (int i = 0; i < refs.length; i++) {
 			IFeatureReference ref = refs[i];
 			VersionedIdentifier refVid = ref.getVersionedIdentifier();
 			if (feature.getVersionedIdentifier().equals(refVid))
 				return ref.getFeature();
 		}
 		return null;
 	}

 	private void preserveOriginatingURLs(
 		IFeature feature,
 		IFeatureReference[] optionalFeatures) {
 		// walk the hieararchy and preserve the originating URL
 		// for all the optional features that are not chosen to
 		// be installed.
 		URL url = feature.getSite().getURL();
 		try {
 			IFeatureReference[] irefs = feature.getIncludedFeatureReferences();
 			for (int i = 0; i < irefs.length; i++) {
 				IFeatureReference iref = irefs[i];
 				boolean preserve = false;
 				if (iref.isOptional()) {
 					boolean onTheList = false;
 					for (int j = 0; j < optionalFeatures.length; j++) {
 						if (optionalFeatures[j].equals(iref)) {
 							//was on the list
 							onTheList = true;
 							break;
 						}
 					}
 					if (!onTheList)
 						preserve = true;
 				}
 				if (preserve) {
 					try {
 						String id =
 							iref.getVersionedIdentifier().getIdentifier();
 						UpdateUIPlugin.setOriginatingURL(id, url);
 					} catch (CoreException e) {
 						// Silently ignore
 					}
 				} else {
 					try {
 						IFeature ifeature = iref.getFeature();
 						preserveOriginatingURLs(ifeature, optionalFeatures);
 					} catch (CoreException e) {
 						// Silently ignore
 					}
 				}
 			}
 		} catch (CoreException e) {
 			// Silently ignore
 		}
 	}
 }
	package org.eclipse.update.internal.ui.wizards;
	/*
	* (c) Copyright IBM Corp. 2000, 2001.
	* All Rights Reserved.
	*/
	import java.lang.reflect.InvocationTargetException;
	import java.net.URL;
	import java.text.DateFormat;
	import java.util.ArrayList;

	import org.eclipse.core.runtime.*;
	import org.eclipse.jface.operation.IRunnableWithProgress;
	import org.eclipse.jface.wizard.IWizardPage;
	import org.eclipse.jface.wizard.Wizard;
	import org.eclipse.update.configuration.*;
	import org.eclipse.update.core.*;
	import org.eclipse.update.core.model.InstallAbortedException;
	import org.eclipse.update.internal.ui.*;
	import org.eclipse.update.internal.ui.UpdateUIPlugin;
	import org.eclipse.update.internal.ui.UpdateUIPluginImages;
	import org.eclipse.update.internal.ui.model.PendingChange;
	import org.eclipse.update.internal.ui.model.UpdateModel;
	import org.eclipse.update.internal.ui.security.JarVerificationService;

	public class InstallWizard extends Wizard {
	private static final String KEY_UNABLE = "InstallWizard.error.unable";
	private static final String KEY_OLD = "InstallWizard.error.old";
	private static final String KEY_SAVED_CONFIG = "InstallWizard.savedConfig";
	private ReviewPage reviewPage;
	private OptionalFeaturesPage optionalFeaturesPage;
	private TargetPage targetPage;
	private PendingChange job;
	private boolean successfulInstall = false;
	private IInstallConfiguration config;
	private boolean patch;

	public InstallWizard(PendingChange job) {
	setDialogSettings(UpdateUIPlugin.getDefault().getDialogSettings());
	setDefaultPageImageDescriptor(UpdateUIPluginImages.DESC_INSTALL_WIZ);
	setForcePreviousAndNextButtons(true);
	setNeedsProgressMonitor(true);
	this.job = job;
	IFeature feature = job.getFeature();
	patch = UpdateUIPlugin.isPatch(feature);
	}

	public boolean isSuccessfulInstall() {
	return successfulInstall;
	}

	/**
	* @see Wizard#performFinish()
	*/
	public boolean performFinish() {
	final IConfiguredSite targetSite =
	(targetPage == null) ? null : targetPage.getTargetSite();
	final IFeatureReference[] optionalFeatures =
	(optionalFeaturesPage == null)
	? null
	: optionalFeaturesPage.getCheckedOptionalFeatures();
	final Object[] optionalElements =
	(optionalFeaturesPage == null)
	? null
	: optionalFeaturesPage.getOptionalElements();
	if (job.getJobType() == PendingChange.INSTALL) {
	ArrayList conflicts =
	DuplicateConflictsDialog.computeDuplicateConflicts(
	job,
	config,
	targetSite,
	optionalFeatures);
	if (conflicts != null) {
	DuplicateConflictsDialog dialog =
	new DuplicateConflictsDialog(getShell(), conflicts);
	if (dialog.open() != 0)
	return false;
	}
	}
	IRunnableWithProgress operation = new IRunnableWithProgress() {
	public void run(IProgressMonitor monitor)
	throws InvocationTargetException {
	try {
	successfulInstall = false;
	makeConfigurationCurrent(config, job);
	execute(
	targetSite,
	optionalElements,
	optionalFeatures,
	monitor);
	saveLocalSite();
	successfulInstall = true;
	} catch (CoreException e) {
	throw new InvocationTargetException(e);
	} finally {
	monitor.done();
	}
	}
	};
	try {
	getContainer().run(true, true, operation);
	} catch (InvocationTargetException e) {
	Throwable target = e.getTargetException();
	if (target instanceof InstallAbortedException) {
	// should we revert to the previous configuration?
	} else {
	UpdateUIPlugin.logException(e);
	}
	return false;
	} catch (InterruptedException e) {
	return false;
	}
	return true;
	}

	public void addPages() {
	reviewPage = new ReviewPage(job);
	addPage(reviewPage);

	config = createInstallConfiguration();

	if (job.getJobType() == PendingChange.INSTALL) {
	if (UpdateModel.hasLicense(job)) {
	addPage(new LicensePage(job));
	}
	if (hasOptionalFeatures(job.getFeature())) {
	optionalFeaturesPage = new OptionalFeaturesPage(job, config);
	addPage(optionalFeaturesPage);
	}
	targetPage = new TargetPage(job, config);
	addPage(targetPage);
	}
	}

	public static IInstallConfiguration createInstallConfiguration() {
	try {
	ILocalSite localSite = SiteManager.getLocalSite();
	IInstallConfiguration config =
	localSite.cloneCurrentConfiguration();
	config.setLabel(Utilities.format(config.getCreationDate()));
	return config;
	} catch (CoreException e) {
	UpdateUIPlugin.logException(e);
	return null;
	}
	}

	public static void makeConfigurationCurrent(IInstallConfiguration config, PendingChange job)
	throws CoreException {
	ILocalSite localSite = SiteManager.getLocalSite();
	if (job!=null && job.getJobType()==PendingChange.INSTALL) {
	if (UpdateUIPlugin.isPatch(job.getFeature())) {
	// Installing a patch - preserve the current configuration
	IInstallConfiguration cconfig = localSite.getCurrentConfiguration();
	IInstallConfiguration savedConfig = localSite.addToPreservedConfigurations(cconfig);
	VersionedIdentifier vid = job.getFeature().getVersionedIdentifier();
	String key = "@"+vid.getIdentifier()+"_"+vid.getVersion();
	String newLabel = UpdateUIPlugin.getFormattedMessage(KEY_SAVED_CONFIG, key);
	savedConfig.setLabel(newLabel);
	UpdateModel model = UpdateUIPlugin.getDefault().getUpdateModel();
	model.fireObjectChanged(savedConfig, null);
	}
	}
	localSite.addConfiguration(config);
	}

	public static void saveLocalSite() throws CoreException {
	ILocalSite localSite = SiteManager.getLocalSite();
	localSite.save();
	}

	public boolean canFinish() {
	IWizardPage page = getContainer().getCurrentPage();
	return page.getNextPage() == null && super.canFinish();
	}

	public IWizardPage getPreviousPage(IWizardPage page) {
	return super.getPreviousPage(page);
	}
	public IWizardPage getNextPage(IWizardPage page) {
	return super.getNextPage(page);
	}
	/*
	* When we are uninstalling, there is no targetSite
	*/
	private void execute(
	IConfiguredSite targetSite,
	Object[] optionalElements,
	IFeatureReference[] optionalFeatures,
	IProgressMonitor monitor)
	throws CoreException {
	IFeature feature = job.getFeature();
	if (job.getJobType() == PendingChange.UNINSTALL) {
	//find the config site of this feature
	IConfiguredSite site = findConfigSite(feature, config);
	if (site != null) {
	site.remove(feature, monitor);
	} else {
	// we should do something here
	throwError(UpdateUIPlugin.getResourceString(KEY_UNABLE));
	}
	} else if (job.getJobType() == PendingChange.INSTALL) {
	if (optionalFeatures == null)
	targetSite.install(feature, getVerificationListener(), monitor);
	else
	targetSite.install(
	feature,
	optionalFeatures,
	getVerificationListener(),
	monitor);
	IFeature oldFeature = job.getOldFeature();
	if (oldFeature != null && !job.isOptionalDelta()) {
	if (optionalElements != null) {
	boolean patch = UpdateUIPlugin.isPatch(feature);
	preserveOptionalState(config, targetSite, patch, optionalElements);
	}
	boolean oldSuccess = unconfigure(config, oldFeature);
	if (!oldSuccess) {
	if (!isNestedChild(oldFeature))
	// "eat" the error if nested child
	throwError(UpdateUIPlugin.getResourceString(KEY_OLD));
	}
	}
	if (oldFeature == null) {
	ensureUnique(config, feature, targetSite);
	if (optionalFeatures != null) {
	preserveOriginatingURLs(feature, optionalFeatures);
	}
	}
	} else if (job.getJobType() == PendingChange.CONFIGURE) {
	configure(feature);
	ensureUnique(config, feature, targetSite);
	} else if (job.getJobType() == PendingChange.UNCONFIGURE) {
	unconfigure(config, job.getFeature());
	} else {
	// should not be here
	return;
	}
	UpdateModel model = UpdateUIPlugin.getDefault().getUpdateModel();
	model.addPendingChange(job);
	}

	static void ensureUnique(
	IInstallConfiguration config,
	IFeature feature,
	IConfiguredSite targetSite)
	throws CoreException {
	boolean patch = false;
	if (targetSite==null)
	targetSite = feature.getSite().getCurrentConfiguredSite();
	IImport[] imports = feature.getImports();
	for (int i = 0; i < imports.length; i++) {
	IImport iimport = imports[i];
	if (iimport.isPatch()) {
	patch = true;
	break;
	}
	}
	// Only need to check features that patch other features.
	if (!patch)
	return;
	IFeature localFeature = findLocalFeature(targetSite, feature);
	ArrayList oldFeatures = new ArrayList();
	// First collect all older active features that
	// have the same ID as new features marked as 'unique'.
	collectOldFeatures(localFeature, targetSite, oldFeatures);
	// Now unconfigure old features to enforce uniqueness
	for (int i = 0; i < oldFeatures.size(); i++) {
	IFeature oldFeature = (IFeature) oldFeatures.get(i);
	unconfigure(config, oldFeature);
	}
	}

	private void throwError(String message) throws CoreException {
	IStatus status =
	new Status(
	IStatus.ERROR,
	UpdateUIPlugin.getPluginId(),
	IStatus.OK,
	message,
	null);
	throw new CoreException(status);
	}

	static IConfiguredSite findConfigSite(
	IFeature feature,
	IInstallConfiguration config)
	throws CoreException {
	IConfiguredSite[] configSites = config.getConfiguredSites();
	for (int i = 0; i < configSites.length; i++) {
	IConfiguredSite site = configSites[i];
	if (site.getSite().equals(feature.getSite())) {
	return site;
	}
	}
	return null;
	}

	private static boolean unconfigure(
	IInstallConfiguration config,
	IFeature feature)
	throws CoreException {
	IConfiguredSite site = findConfigSite(feature, config);
	if (site != null) {
	PatchCleaner cleaner = new PatchCleaner(site, feature);
	boolean result = site.unconfigure(feature);
	cleaner.dispose();
	return result;
	}
	return false;
	}

	private void configure(IFeature feature) throws CoreException {
	IConfiguredSite site = findConfigSite(feature, config);
	if (site != null) {
	site.configure(feature);
	}
	}

	private IVerificationListener getVerificationListener() {
	return new JarVerificationService(this.getShell());
	}

	private boolean isNestedChild(IFeature feature) {
	IConfiguredSite[] csites = config.getConfiguredSites();
	try {
	for (int i = 0; csites != null && i < csites.length; i++) {
	IFeatureReference[] refs = csites[i].getConfiguredFeatures();
	for (int j = 0; refs != null && j < refs.length; j++) {
	IFeature parent = refs[j].getFeature();
	IFeatureReference[] children =
	parent.getIncludedFeatureReferences();
	for (int k = 0;
	children != null && k < children.length;
	k++) {
	IFeature child = children[k].getFeature();
	if (feature.equals(child))
	return true;
	}
	}
	}
	} catch (CoreException e) {
	// will return false
	}
	return false;
	}

	static boolean hasOptionalFeatures(IFeatureReference fref) {
	try {
	return hasOptionalFeatures(fref.getFeature());
	} catch (CoreException e) {
	return false;
	}
	}
	static boolean hasOptionalFeatures(IFeature feature) {
	try {
	IFeatureReference[] irefs = feature.getIncludedFeatureReferences();
	for (int i = 0; i < irefs.length; i++) {
	IFeatureReference iref = irefs[i];
	if (iref.isOptional())
	return true;
	// see if it has optional children
	IFeature child = iref.getFeature();
	if (hasOptionalFeatures(child))
	return true;
	}
	} catch (CoreException e) {
	}
	return false;
	}

	static void preserveOptionalState(
	IInstallConfiguration config,
	IConfiguredSite targetSite,
	boolean patch,
	Object[] optionalElements) {
	for (int i = 0; i < optionalElements.length; i++) {
	FeatureHierarchyElement fe =
	(FeatureHierarchyElement) optionalElements[i];
	Object[] children = fe.getChildren(true, patch, config);
	preserveOptionalState(config, targetSite, patch, children);
	if (!fe.isEnabled(config)) {
	IFeature newFeature = fe.getFeature();
	try {
	IFeature localFeature =
	findLocalFeature(targetSite, newFeature);
	if (localFeature != null)
	targetSite.unconfigure(localFeature);
	} catch (CoreException e) {
	// Eat this - we will leave with it
	}
	}
	}
	}

	static void collectOldFeatures(
	IFeature feature,
	IConfiguredSite targetSite,
	ArrayList result)
	throws CoreException {
	IFeatureReference[] included = feature.getIncludedFeatureReferences();
	for (int i = 0; i < included.length; i++) {
	IFeatureReference iref = included[i];
	IFeature ifeature;

	try {
	ifeature = iref.getFeature();
	}
	catch (CoreException e) {
	if (iref.isOptional())
	continue;
	throw e;
	}
	// find other features and unconfigure
	String id = iref.getVersionedIdentifier().getIdentifier();
	IFeature[] sameIds =
	UpdateUIPlugin.searchSite(id, targetSite, true);
	for (int j = 0; j < sameIds.length; j++) {
	IFeature sameId = sameIds[j];
	// Ignore self.
	if (sameId.equals(ifeature))
	continue;
	result.add(sameId);
	}
	collectOldFeatures(ifeature, targetSite, result);
	}
	}

	private static IFeature findLocalFeature(
	IConfiguredSite csite,
	IFeature feature)
	throws CoreException {
	IFeatureReference[] refs = csite.getConfiguredFeatures();
	for (int i = 0; i < refs.length; i++) {
	IFeatureReference ref = refs[i];
	VersionedIdentifier refVid = ref.getVersionedIdentifier();
	if (feature.getVersionedIdentifier().equals(refVid))
	return ref.getFeature();
	}
	return null;
	}

	private void preserveOriginatingURLs(
	IFeature feature,
	IFeatureReference[] optionalFeatures) {
	// walk the hieararchy and preserve the originating URL
	// for all the optional features that are not chosen to
	// be installed.
	URL url = feature.getSite().getURL();
	try {
	IFeatureReference[] irefs = feature.getIncludedFeatureReferences();
	for (int i = 0; i < irefs.length; i++) {
	IFeatureReference iref = irefs[i];
	boolean preserve = false;
	if (iref.isOptional()) {
	boolean onTheList = false;
	for (int j = 0; j < optionalFeatures.length; j++) {
	if (optionalFeatures[j].equals(iref)) {
	//was on the list
	onTheList = true;
	break;
	}
	}
	if (!onTheList)
	preserve = true;
	}
	if (preserve) {
	try {
	String id =
	iref.getVersionedIdentifier().getIdentifier();
	UpdateUIPlugin.setOriginatingURL(id, url);
	} catch (CoreException e) {
	// Silently ignore
	}
	} else {
	try {
	IFeature ifeature = iref.getFeature();
	preserveOriginatingURLs(ifeature, optionalFeatures);
	} catch (CoreException e) {
	// Silently ignore
	}
	}
	}
	} catch (CoreException e) {
	// Silently ignore
	}
	}
	}