bundles/org.eclipse.equinox.p2.reconciler.dropins/src/org/eclipse/equinox/internal/p2/reconciler/dropins/ProfileSynchronizer.java - equinox/rt.equinox.p2 - Git at Google

 /*******************************************************************************
  * Copyright (c) 2007, 2009 IBM Corporation 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:
  * IBM Corporation - initial implementation and ideas
  ******************************************************************************/
 package org.eclipse.equinox.internal.p2.reconciler.dropins;

 import org.eclipse.equinox.p2.core.ProvisionException;

 import java.io.*;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.util.*;
 import java.util.Map.Entry;
 import org.eclipse.core.runtime.*;
 import org.eclipse.equinox.internal.p2.core.helpers.*;
 import org.eclipse.equinox.internal.p2.extensionlocation.Constants;
 import org.eclipse.equinox.internal.provisional.configurator.Configurator;
 import org.eclipse.equinox.internal.provisional.p2.director.*;
 import org.eclipse.equinox.internal.provisional.p2.metadata.query.Collector;
 import org.eclipse.equinox.internal.provisional.p2.metadata.query.InstallableUnitQuery;
 import org.eclipse.equinox.p2.engine.*;
 import org.eclipse.equinox.p2.engine.query.IUProfilePropertyQuery;
 import org.eclipse.equinox.p2.metadata.IInstallableUnit;
 import org.eclipse.equinox.p2.metadata.query.GroupQuery;
 import org.eclipse.equinox.p2.metadata.query.IQueryResult;
 import org.eclipse.equinox.p2.repository.IRepository;
 import org.eclipse.equinox.p2.repository.artifact.IArtifactRepository;
 import org.eclipse.equinox.p2.repository.artifact.IFileArtifactRepository;
 import org.eclipse.equinox.p2.repository.metadata.IMetadataRepository;
 import org.eclipse.osgi.service.environment.EnvironmentInfo;
 import org.osgi.framework.BundleContext;
 import org.osgi.framework.ServiceReference;

 /**
  * Synchronizes a profile with a set of repositories.
  */
 public class ProfileSynchronizer {
 	private static final String RECONCILER_APPLICATION_ID = "org.eclipse.equinox.p2.reconciler.application"; //$NON-NLS-1$
 	private static final String TIMESTAMPS_FILE_PREFIX = "timestamps"; //$NON-NLS-1$
 	private static final String PROFILE_TIMESTAMP = "PROFILE"; //$NON-NLS-1$
 	private static final String NO_TIMESTAMP = "-1"; //$NON-NLS-1$
 	private static final String PROP_FROM_DROPINS = "org.eclipse.equinox.p2.reconciler.dropins"; //$NON-NLS-1$

 	private static final String CACHE_EXTENSIONS = "org.eclipse.equinox.p2.cache.extensions"; //$NON-NLS-1$
 	private static final String PIPE = "|"; //$NON-NLS-1$
 	private static final String EXPLANATION = "org.eclipse.equinox.p2.director.explain"; //$NON-NLS-1$
 	final IProfile profile;

 	final Map<String, IMetadataRepository> repositoryMap;
 	private Map<String, String> timestamps;

 	/*
 	 * Constructor for the class.
 	 */
 	public ProfileSynchronizer(IProfile profile, Collection<IMetadataRepository> repositories) {
 		this.profile = profile;
 		this.repositoryMap = new HashMap<String, IMetadataRepository>();
 		for (IMetadataRepository repository : repositories) {
 			repositoryMap.put(repository.getLocation().toString(), repository);
 		}
 	}

 	/*
 	 * Synchronize the profile with the list of metadata repositories.
 	 */
 	public IStatus synchronize(IProgressMonitor monitor) {
 		readTimestamps();
 		if (isUpToDate())
 			return Status.OK_STATUS;

 		ProvisioningContext context = getContext();
 		context.setProperty(EXPLANATION, Boolean.FALSE.toString());

 		ProfileChangeRequest request = createProfileChangeRequest(context);
 		String updatedCacheExtensions = synchronizeCacheExtensions();
 		if (request == null) {
 			if (updatedCacheExtensions != null) {
 				IStatus engineResult = setProperty(CACHE_EXTENSIONS, updatedCacheExtensions, context, null);
 				if (engineResult.getSeverity() != IStatus.ERROR && engineResult.getSeverity() != IStatus.CANCEL)
 					writeTimestamps();
 				return engineResult;
 			}
 			return Status.OK_STATUS;
 		}
 		if (updatedCacheExtensions != null)
 			request.setProfileProperty(CACHE_EXTENSIONS, updatedCacheExtensions);

 		SubMonitor sub = SubMonitor.convert(monitor, 100);
 		try {
 			//create the provisioning plan
 			IProvisioningPlan plan = createProvisioningPlan(request, context, sub.newChild(50));
 			IStatus status = plan.getStatus();
 			if (status.getSeverity() == IStatus.ERROR || status.getSeverity() == IStatus.CANCEL)
 				return status;

 			if (plan.getAdditions().query(InstallableUnitQuery.ANY, null).isEmpty() && plan.getRemovals().query(InstallableUnitQuery.ANY, null).isEmpty()) {
 				writeTimestamps();
 				return status;
 			}

 			//invoke the engine to perform installs/uninstalls
 			IStatus engineResult = executePlan(plan, context, sub.newChild(50));
 			if (engineResult.getSeverity() == IStatus.ERROR || engineResult.getSeverity() == IStatus.CANCEL)
 				return engineResult;

 			writeTimestamps();

 			return applyConfiguration(false);
 		} finally {
 			sub.done();
 		}
 	}

 	private void writeTimestamps() {
 		timestamps.clear();
 		timestamps.put(PROFILE_TIMESTAMP, Long.toString(profile.getTimestamp()));
 		for (Entry<String, IMetadataRepository> entry : repositoryMap.entrySet()) {
 			IMetadataRepository repository = entry.getValue();
 			Map<String, String> props = repository.getProperties();
 			String timestamp = null;
 			if (props != null)
 				timestamp = props.get(IRepository.PROP_TIMESTAMP);

 			if (timestamp == null)
 				timestamp = NO_TIMESTAMP;

 			timestamps.put(entry.getKey(), timestamp);
 		}

 		try {
 			File file = Activator.getContext().getDataFile(TIMESTAMPS_FILE_PREFIX + profile.getProfileId().hashCode());
 			OutputStream os = new BufferedOutputStream(new FileOutputStream(file));
 			try {
 				CollectionUtils.storeProperties(timestamps, os, "Timestamps for " + profile.getProfileId()); //$NON-NLS-1$
 			} finally {
 				if (os != null)
 					os.close();
 			}
 		} catch (FileNotFoundException e) {
 			//Ignore
 		} catch (IOException e) {
 			//Ignore
 		}
 	}

 	private boolean isUpToDate() {
 		// the user might want to force a reconciliation
 		if ("true".equals(Activator.getContext().getProperty("osgi.checkConfiguration"))) //$NON-NLS-1$//$NON-NLS-2$
 			return false;

 		String lastKnownProfileTimeStamp = timestamps.remove(PROFILE_TIMESTAMP);
 		if (lastKnownProfileTimeStamp == null)
 			return false;
 		if (!lastKnownProfileTimeStamp.equals(Long.toString(profile.getTimestamp())))
 			return false;

 		//When we get here the timestamps map only contains information related to repos
 		for (Entry<String, IMetadataRepository> entry : repositoryMap.entrySet()) {
 			IMetadataRepository repository = entry.getValue();

 			Map<String, String> props = repository.getProperties();
 			String currentTimestamp = null;
 			if (props != null)
 				currentTimestamp = props.get(IRepository.PROP_TIMESTAMP);

 			if (currentTimestamp == null)
 				currentTimestamp = NO_TIMESTAMP;

 			String lastKnownTimestamp = timestamps.remove(entry.getKey());
 			//A repo has been added
 			if (lastKnownTimestamp == null)
 				return false;
 			if (!lastKnownTimestamp.equals(currentTimestamp)) {
 				return false;
 			}
 		}
 		//A repo has been removed
 		if (timestamps.size() != 0)
 			return false;

 		return true;
 	}

 	private void readTimestamps() {
 		File file = Activator.getContext().getDataFile(TIMESTAMPS_FILE_PREFIX + profile.getProfileId().hashCode());
 		try {
 			InputStream is = new BufferedInputStream(new FileInputStream(file));
 			try {
 				timestamps = CollectionUtils.loadProperties(is);
 			} finally {
 				if (is != null)
 					is.close();
 			}
 		} catch (FileNotFoundException e) {
 			timestamps = new HashMap<String, String>();
 			//Ignore
 		} catch (IOException e) {
 			//Ignore
 			timestamps = new HashMap<String, String>();
 		}
 	}

 	private ProvisioningContext getContext() {
 		ArrayList<URI> repoURLs = new ArrayList<URI>();
 		for (Iterator<String> iterator = repositoryMap.keySet().iterator(); iterator.hasNext();) {
 			try {
 				repoURLs.add(new URI(iterator.next()));
 			} catch (URISyntaxException e) {
 				//ignore
 			}
 		}
 		ProvisioningContext result = new ProvisioningContext(repoURLs.toArray(new URI[repoURLs.size()]));
 		result.setArtifactRepositories(new URI[0]);
 		return result;
 	}

 	private String synchronizeCacheExtensions() {
 		List<String> currentExtensions = new ArrayList<String>();
 		StringBuffer buffer = new StringBuffer();

 		List<String> repositories = new ArrayList<String>(repositoryMap.keySet());
 		final String OSGiInstallArea = Activator.getOSGiInstallArea().toExternalForm() + Constants.EXTENSION_LOCATION;
 		Collections.sort(repositories, new Comparator<String>() {
 			public int compare(String left, String right) {
 				if (OSGiInstallArea.equals(left))
 					return -1;
 				if (OSGiInstallArea.equals(right))
 					return 1;
 				return left.compareTo(right);
 			}
 		});
 		for (Iterator<String> it = repositories.iterator(); it.hasNext();) {
 			String repositoryId = it.next();
 			try {
 				IArtifactRepository repository = Activator.loadArtifactRepository(new URI(repositoryId), null);

 				if (repository instanceof IFileArtifactRepository) {
 					currentExtensions.add(escapePipe(repositoryId));
 					buffer.append(repositoryId);
 					if (it.hasNext())
 						buffer.append(PIPE);
 				}
 			} catch (ProvisionException e) {
 				// ignore
 			} catch (URISyntaxException e) {
 				// unexpected
 				e.printStackTrace();
 			}
 		}
 		String currentExtensionsProperty = (buffer.length() == 0) ? null : buffer.toString();

 		List<String> previousExtensions = new ArrayList<String>();
 		String previousExtensionsProperty = profile.getProperty(CACHE_EXTENSIONS);
 		if (previousExtensionsProperty != null) {
 			StringTokenizer tokenizer = new StringTokenizer(previousExtensionsProperty, PIPE);
 			while (tokenizer.hasMoreTokens()) {
 				previousExtensions.add(tokenizer.nextToken());
 			}
 		}

 		if (previousExtensions.size() == currentExtensions.size() && previousExtensions.containsAll(currentExtensions))
 			return null;

 		return currentExtensionsProperty;
 	}

 	/**
 	 * Escapes the pipe ('|') character in a URI using the standard URI escape sequence.
 	 * This is done because the pipe character is used as the delimiter between locations
 	 * in the cache extensions profile property.
 	 */
 	private String escapePipe(String location) {
 		String result = location;
 		int pipeIndex;
 		while ((pipeIndex = result.indexOf(',')) != -1)
 			result = result.substring(0, pipeIndex) + "%7C" + result.substring(pipeIndex + 1); //$NON-NLS-1$
 		return result;
 	}

 	public ProfileChangeRequest createProfileChangeRequest(ProvisioningContext context) {
 		ProfileChangeRequest request = new ProfileChangeRequest(profile);

 		boolean resolve = Boolean.valueOf(profile.getProperty("org.eclipse.equinox.p2.resolve")).booleanValue(); //$NON-NLS-1$
 		if (resolve)
 			request.removeProfileProperty("org.eclipse.equinox.p2.resolve"); //$NON-NLS-1$

 		List<IInstallableUnit> toAdd = new ArrayList<IInstallableUnit>();
 		List<IInstallableUnit> toRemove = new ArrayList<IInstallableUnit>();

 		boolean foundIUsToAdd = false;
 		Set<IInstallableUnit> profileIUs = profile.query(InstallableUnitQuery.ANY, null).unmodifiableSet();

 		// we use IProfile.available(...) here so that we also gather any shared IUs
 		Set<IInstallableUnit> availableProfileIUs = profile.available(InstallableUnitQuery.ANY, null).unmodifiableSet();

 		// get all IUs from all our repos (toAdd)
 		IQueryResult<IInstallableUnit> allIUs = getAllIUsFromRepos();
 		for (Iterator<IInstallableUnit> iter = allIUs.iterator(); iter.hasNext();) {
 			final IInstallableUnit iu = iter.next();
 			// if the IU is already installed in the profile then skip it
 			if (!profileIUs.contains(iu)) {
 				if (GroupQuery.isGroup(iu))
 					request.setInstallableUnitProfileProperty(iu, IProfile.PROP_PROFILE_ROOT_IU, Boolean.TRUE.toString());
 				// mark all IUs with special property
 				request.setInstallableUnitProfileProperty(iu, PROP_FROM_DROPINS, Boolean.TRUE.toString());
 				request.setInstallableUnitInclusionRules(iu, PlannerHelper.createOptionalInclusionRule(iu));
 				request.setInstallableUnitProfileProperty(iu, IProfile.PROP_PROFILE_LOCKED_IU, Integer.toString(IProfile.LOCK_UNINSTALL));
 				toAdd.add(iu);

 				// as soon as we find something locally that needs to be installed, then
 				// everything from the parent's dropins must be installed locally as well.
 				if (!foundIUsToAdd && !availableProfileIUs.contains(iu)) {
 					foundIUsToAdd = true;
 				}
 			}
 		}

 		// get all IUs from profile with marked property (existing)
 		IQueryResult<IInstallableUnit> dropinIUs = profile.query(new IUProfilePropertyQuery(PROP_FROM_DROPINS, Boolean.toString(true)), null);
 		Set<IInstallableUnit> all = allIUs.unmodifiableSet();
 		for (Iterator<IInstallableUnit> iter = dropinIUs.iterator(); iter.hasNext();) {
 			IInstallableUnit iu = iter.next();
 			// the STRICT policy is set when we install things via the UI, we use it to differentiate between IUs installed
 			// via the dropins and the UI. (dropins are considered optional) If an IU has both properties set it means that
 			// it was initially installed via the dropins but then upgraded via the UI. (properties are copied from the old IU
 			// to the new IU during an upgrade) In this case we want to remove the "from dropins" property so the upgrade
 			// will stick.
 			if ("STRICT".equals(profile.getInstallableUnitProperty(iu, "org.eclipse.equinox.p2.internal.inclusion.rules"))) { //$NON-NLS-1$//$NON-NLS-2$
 				request.removeInstallableUnitProfileProperty(iu, PROP_FROM_DROPINS);
 				request.removeInstallableUnitProfileProperty(iu, IProfile.PROP_PROFILE_LOCKED_IU);
 				continue;
 			}
 			// remove the IUs that are in the intersection between the 2 sets
 			if (all.contains(iu))
 				toAdd.remove(iu);
 			else
 				toRemove.add(iu);
 		}

 		if (!foundIUsToAdd && toRemove.isEmpty() && !resolve) {
 			if (Tracing.DEBUG_RECONCILER)
 				Tracing.debug("[reconciler] Nothing to do."); //$NON-NLS-1$
 			return null;
 		}

 		context.setExtraIUs(toAdd);
 		request.addInstallableUnits(toAdd.toArray(new IInstallableUnit[toAdd.size()]));
 		request.removeInstallableUnits(toRemove.toArray(new IInstallableUnit[toRemove.size()]));
 		debug(request);
 		return request;
 	}

 	/*
 	 * If debugging is turned on, then print out the details for the given profile change request.
 	 */
 	private void debug(ProfileChangeRequest request) {
 		if (!Tracing.DEBUG_RECONCILER)
 			return;
 		final String PREFIX = "[reconciler] "; //$NON-NLS-1$
 		IInstallableUnit[] toAdd = request.getAddedInstallableUnits();
 		if (toAdd == null || toAdd.length == 0) {
 			Tracing.debug(PREFIX + "No installable units to add."); //$NON-NLS-1$
 		} else {
 			for (int i = 0; i < toAdd.length; i++) {
 				Tracing.debug(PREFIX + "Adding IU: " + toAdd[i].getId() + ' ' + toAdd[i].getVersion()); //$NON-NLS-1$
 			}
 		}
 		Map<IInstallableUnit, Map<String, String>> propsToAdd = request.getInstallableUnitProfilePropertiesToAdd();
 		if (propsToAdd == null || propsToAdd.isEmpty()) {
 			Tracing.debug(PREFIX + "No IU properties to add."); //$NON-NLS-1$
 		} else {
 			for (Entry<IInstallableUnit, Map<String, String>> entry : propsToAdd.entrySet()) {
 				Tracing.debug(PREFIX + "Adding IU property: " + entry.getKey() + "->" + entry.getValue()); //$NON-NLS-1$ //$NON-NLS-2$
 			}
 		}

 		IInstallableUnit[] toRemove = request.getRemovedInstallableUnits();
 		if (toRemove == null || toRemove.length == 0) {
 			Tracing.debug(PREFIX + "No installable units to remove."); //$NON-NLS-1$
 		} else {
 			for (int i = 0; i < toRemove.length; i++) {
 				Tracing.debug(PREFIX + "Removing IU: " + toRemove[i].getId() + ' ' + toRemove[i].getVersion()); //$NON-NLS-1$
 			}
 		}
 		Map<IInstallableUnit, List<String>> propsToRemove = request.getInstallableUnitProfilePropertiesToRemove();
 		if (propsToRemove == null || propsToRemove.isEmpty()) {
 			Tracing.debug(PREFIX + "No IU properties to remove."); //$NON-NLS-1$
 		} else {
 			for (Entry<IInstallableUnit, List<String>> entry : propsToRemove.entrySet()) {
 				Tracing.debug(PREFIX + "Removing IU property: " + entry.getKey() + "->" + entry.getValue()); //$NON-NLS-1$ //$NON-NLS-2$
 			}
 		}
 	}

 	private IQueryResult<IInstallableUnit> getAllIUsFromRepos() {
 		// TODO: Should consider using a sequenced iterator here instead of collecting
 		Collector<IInstallableUnit> allRepos = new Collector<IInstallableUnit>();
 		for (IMetadataRepository repository : repositoryMap.values()) {
 			allRepos.addAll(repository.query(InstallableUnitQuery.ANY, null));
 		}
 		return allRepos;
 	}

 	private IProvisioningPlan createProvisioningPlan(ProfileChangeRequest request, ProvisioningContext provisioningContext, IProgressMonitor monitor) {
 		BundleContext context = Activator.getContext();
 		ServiceReference reference = context.getServiceReference(IPlanner.SERVICE_NAME);
 		IPlanner planner = (IPlanner) context.getService(reference);

 		try {
 			return planner.getProvisioningPlan(request, provisioningContext, monitor);
 		} finally {
 			context.ungetService(reference);
 		}
 	}

 	private IStatus setProperty(String key, String value, ProvisioningContext provisioningContext, IProgressMonitor monitor) {
 		BundleContext context = Activator.getContext();
 		ServiceReference reference = context.getServiceReference(IEngine.SERVICE_NAME);
 		IEngine engine = (IEngine) context.getService(reference);
 		ServiceReference plannerReference = context.getServiceReference(IPlanner.SERVICE_NAME);
 		IPlanner planner = (IPlanner) context.getService(reference);
 		try {
 			ProfileChangeRequest addPropertyRequest = new ProfileChangeRequest(profile);
 			addPropertyRequest.setProfileProperty(key, value);
 			IProvisioningPlan plan = planner.getProvisioningPlan(addPropertyRequest, provisioningContext, monitor);
 			IPhaseSet phaseSet = engine.createPhaseSetExcluding(new String[] {IPhaseSet.PHASE_COLLECT, IPhaseSet.PHASE_CHECK_TRUST});
 			return engine.perform(plan, phaseSet, monitor);
 		} finally {
 			context.ungetService(reference);
 			context.ungetService(plannerReference);
 		}
 	}

 	private IStatus executePlan(IProvisioningPlan plan, ProvisioningContext provisioningContext, IProgressMonitor monitor) {
 		BundleContext context = Activator.getContext();
 		ServiceReference reference = context.getServiceReference(IEngine.SERVICE_NAME);
 		IEngine engine = (IEngine) context.getService(reference);
 		try {
 			IPhaseSet phaseSet = engine.createPhaseSetExcluding(new String[] {IPhaseSet.PHASE_COLLECT, IPhaseSet.PHASE_CHECK_TRUST});

 			if (plan.getInstallerPlan() != null) {
 				IStatus installerPlanStatus = engine.perform(plan.getInstallerPlan(), phaseSet, monitor);
 				if (!installerPlanStatus.isOK())
 					return installerPlanStatus;

 				applyConfiguration(true);
 			}
 			return engine.perform(plan, phaseSet, monitor);
 		} finally {
 			context.ungetService(reference);
 		}
 	}

 	/*
 	 * Write out the configuration file.
 	 */
 	private IStatus applyConfiguration(boolean isInstaller) {
 		if (!isInstaller && isReconciliationApplicationRunning())
 			return Status.OK_STATUS;
 		BundleContext context = Activator.getContext();
 		ServiceReference reference = context.getServiceReference(Configurator.class.getName());
 		Configurator configurator = (Configurator) context.getService(reference);
 		try {
 			configurator.applyConfiguration();
 		} catch (IOException e) {
 			return new Status(IStatus.ERROR, Activator.ID, "Unexpected failure applying configuration", e); //$NON-NLS-1$
 		} finally {
 			context.ungetService(reference);
 		}
 		return Status.OK_STATUS;
 	}

 	static boolean isReconciliationApplicationRunning() {
 		EnvironmentInfo info = (EnvironmentInfo) ServiceHelper.getService(Activator.getContext(), EnvironmentInfo.class.getName());
 		if (info == null)
 			return false;
 		String[] args = info.getCommandLineArgs();
 		if (args == null)
 			return false;
 		for (int i = 0; i < args.length; i++) {
 			if (args[i] != null && RECONCILER_APPLICATION_ID.equals(args[i].trim()))
 				return true;
 		}
 		return false;
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2007, 2009 IBM Corporation 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:
	* IBM Corporation - initial implementation and ideas
	******************************************************************************/
	package org.eclipse.equinox.internal.p2.reconciler.dropins;

	import org.eclipse.equinox.p2.core.ProvisionException;

	import java.io.*;
	import java.net.URI;
	import java.net.URISyntaxException;
	import java.util.*;
	import java.util.Map.Entry;
	import org.eclipse.core.runtime.*;
	import org.eclipse.equinox.internal.p2.core.helpers.*;
	import org.eclipse.equinox.internal.p2.extensionlocation.Constants;
	import org.eclipse.equinox.internal.provisional.configurator.Configurator;
	import org.eclipse.equinox.internal.provisional.p2.director.*;
	import org.eclipse.equinox.internal.provisional.p2.metadata.query.Collector;
	import org.eclipse.equinox.internal.provisional.p2.metadata.query.InstallableUnitQuery;
	import org.eclipse.equinox.p2.engine.*;
	import org.eclipse.equinox.p2.engine.query.IUProfilePropertyQuery;
	import org.eclipse.equinox.p2.metadata.IInstallableUnit;
	import org.eclipse.equinox.p2.metadata.query.GroupQuery;
	import org.eclipse.equinox.p2.metadata.query.IQueryResult;
	import org.eclipse.equinox.p2.repository.IRepository;
	import org.eclipse.equinox.p2.repository.artifact.IArtifactRepository;
	import org.eclipse.equinox.p2.repository.artifact.IFileArtifactRepository;
	import org.eclipse.equinox.p2.repository.metadata.IMetadataRepository;
	import org.eclipse.osgi.service.environment.EnvironmentInfo;
	import org.osgi.framework.BundleContext;
	import org.osgi.framework.ServiceReference;

	/**
	* Synchronizes a profile with a set of repositories.
	*/
	public class ProfileSynchronizer {
	private static final String RECONCILER_APPLICATION_ID = "org.eclipse.equinox.p2.reconciler.application"; //$NON-NLS-1$
	private static final String TIMESTAMPS_FILE_PREFIX = "timestamps"; //$NON-NLS-1$
	private static final String PROFILE_TIMESTAMP = "PROFILE"; //$NON-NLS-1$
	private static final String NO_TIMESTAMP = "-1"; //$NON-NLS-1$
	private static final String PROP_FROM_DROPINS = "org.eclipse.equinox.p2.reconciler.dropins"; //$NON-NLS-1$

	private static final String CACHE_EXTENSIONS = "org.eclipse.equinox.p2.cache.extensions"; //$NON-NLS-1$
	private static final String PIPE = "\|"; //$NON-NLS-1$
	private static final String EXPLANATION = "org.eclipse.equinox.p2.director.explain"; //$NON-NLS-1$
	final IProfile profile;

	final Map<String, IMetadataRepository> repositoryMap;
	private Map<String, String> timestamps;

	/*
	* Constructor for the class.
	*/
	public ProfileSynchronizer(IProfile profile, Collection<IMetadataRepository> repositories) {
	this.profile = profile;
	this.repositoryMap = new HashMap<String, IMetadataRepository>();
	for (IMetadataRepository repository : repositories) {
	repositoryMap.put(repository.getLocation().toString(), repository);
	}
	}

	/*
	* Synchronize the profile with the list of metadata repositories.
	*/
	public IStatus synchronize(IProgressMonitor monitor) {
	readTimestamps();
	if (isUpToDate())
	return Status.OK_STATUS;

	ProvisioningContext context = getContext();
	context.setProperty(EXPLANATION, Boolean.FALSE.toString());

	ProfileChangeRequest request = createProfileChangeRequest(context);
	String updatedCacheExtensions = synchronizeCacheExtensions();
	if (request == null) {
	if (updatedCacheExtensions != null) {
	IStatus engineResult = setProperty(CACHE_EXTENSIONS, updatedCacheExtensions, context, null);
	if (engineResult.getSeverity() != IStatus.ERROR && engineResult.getSeverity() != IStatus.CANCEL)
	writeTimestamps();
	return engineResult;
	}
	return Status.OK_STATUS;
	}
	if (updatedCacheExtensions != null)
	request.setProfileProperty(CACHE_EXTENSIONS, updatedCacheExtensions);

	SubMonitor sub = SubMonitor.convert(monitor, 100);
	try {
	//create the provisioning plan
	IProvisioningPlan plan = createProvisioningPlan(request, context, sub.newChild(50));
	IStatus status = plan.getStatus();
	if (status.getSeverity() == IStatus.ERROR \|\| status.getSeverity() == IStatus.CANCEL)
	return status;

	if (plan.getAdditions().query(InstallableUnitQuery.ANY, null).isEmpty() && plan.getRemovals().query(InstallableUnitQuery.ANY, null).isEmpty()) {
	writeTimestamps();
	return status;
	}

	//invoke the engine to perform installs/uninstalls
	IStatus engineResult = executePlan(plan, context, sub.newChild(50));
	if (engineResult.getSeverity() == IStatus.ERROR \|\| engineResult.getSeverity() == IStatus.CANCEL)
	return engineResult;

	writeTimestamps();

	return applyConfiguration(false);
	} finally {
	sub.done();
	}
	}

	private void writeTimestamps() {
	timestamps.clear();
	timestamps.put(PROFILE_TIMESTAMP, Long.toString(profile.getTimestamp()));
	for (Entry<String, IMetadataRepository> entry : repositoryMap.entrySet()) {
	IMetadataRepository repository = entry.getValue();
	Map<String, String> props = repository.getProperties();
	String timestamp = null;
	if (props != null)
	timestamp = props.get(IRepository.PROP_TIMESTAMP);

	if (timestamp == null)
	timestamp = NO_TIMESTAMP;

	timestamps.put(entry.getKey(), timestamp);
	}

	try {
	File file = Activator.getContext().getDataFile(TIMESTAMPS_FILE_PREFIX + profile.getProfileId().hashCode());
	OutputStream os = new BufferedOutputStream(new FileOutputStream(file));
	try {
	CollectionUtils.storeProperties(timestamps, os, "Timestamps for " + profile.getProfileId()); //$NON-NLS-1$
	} finally {
	if (os != null)
	os.close();
	}
	} catch (FileNotFoundException e) {
	//Ignore
	} catch (IOException e) {
	//Ignore
	}
	}

	private boolean isUpToDate() {
	// the user might want to force a reconciliation
	if ("true".equals(Activator.getContext().getProperty("osgi.checkConfiguration"))) //$NON-NLS-1$//$NON-NLS-2$
	return false;

	String lastKnownProfileTimeStamp = timestamps.remove(PROFILE_TIMESTAMP);
	if (lastKnownProfileTimeStamp == null)
	return false;
	if (!lastKnownProfileTimeStamp.equals(Long.toString(profile.getTimestamp())))
	return false;

	//When we get here the timestamps map only contains information related to repos
	for (Entry<String, IMetadataRepository> entry : repositoryMap.entrySet()) {
	IMetadataRepository repository = entry.getValue();

	Map<String, String> props = repository.getProperties();
	String currentTimestamp = null;
	if (props != null)
	currentTimestamp = props.get(IRepository.PROP_TIMESTAMP);

	if (currentTimestamp == null)
	currentTimestamp = NO_TIMESTAMP;

	String lastKnownTimestamp = timestamps.remove(entry.getKey());
	//A repo has been added
	if (lastKnownTimestamp == null)
	return false;
	if (!lastKnownTimestamp.equals(currentTimestamp)) {
	return false;
	}
	}
	//A repo has been removed
	if (timestamps.size() != 0)
	return false;

	return true;
	}

	private void readTimestamps() {
	File file = Activator.getContext().getDataFile(TIMESTAMPS_FILE_PREFIX + profile.getProfileId().hashCode());
	try {
	InputStream is = new BufferedInputStream(new FileInputStream(file));
	try {
	timestamps = CollectionUtils.loadProperties(is);
	} finally {
	if (is != null)
	is.close();
	}
	} catch (FileNotFoundException e) {
	timestamps = new HashMap<String, String>();
	//Ignore
	} catch (IOException e) {
	//Ignore
	timestamps = new HashMap<String, String>();
	}
	}

	private ProvisioningContext getContext() {
	ArrayList<URI> repoURLs = new ArrayList<URI>();
	for (Iterator<String> iterator = repositoryMap.keySet().iterator(); iterator.hasNext();) {
	try {
	repoURLs.add(new URI(iterator.next()));
	} catch (URISyntaxException e) {
	//ignore
	}
	}
	ProvisioningContext result = new ProvisioningContext(repoURLs.toArray(new URI[repoURLs.size()]));
	result.setArtifactRepositories(new URI[0]);
	return result;
	}

	private String synchronizeCacheExtensions() {
	List<String> currentExtensions = new ArrayList<String>();
	StringBuffer buffer = new StringBuffer();

	List<String> repositories = new ArrayList<String>(repositoryMap.keySet());
	final String OSGiInstallArea = Activator.getOSGiInstallArea().toExternalForm() + Constants.EXTENSION_LOCATION;
	Collections.sort(repositories, new Comparator<String>() {
	public int compare(String left, String right) {
	if (OSGiInstallArea.equals(left))
	return -1;
	if (OSGiInstallArea.equals(right))
	return 1;
	return left.compareTo(right);
	}
	});
	for (Iterator<String> it = repositories.iterator(); it.hasNext();) {
	String repositoryId = it.next();
	try {
	IArtifactRepository repository = Activator.loadArtifactRepository(new URI(repositoryId), null);

	if (repository instanceof IFileArtifactRepository) {
	currentExtensions.add(escapePipe(repositoryId));
	buffer.append(repositoryId);
	if (it.hasNext())
	buffer.append(PIPE);
	}
	} catch (ProvisionException e) {
	// ignore
	} catch (URISyntaxException e) {
	// unexpected
	e.printStackTrace();
	}
	}
	String currentExtensionsProperty = (buffer.length() == 0) ? null : buffer.toString();

	List<String> previousExtensions = new ArrayList<String>();
	String previousExtensionsProperty = profile.getProperty(CACHE_EXTENSIONS);
	if (previousExtensionsProperty != null) {
	StringTokenizer tokenizer = new StringTokenizer(previousExtensionsProperty, PIPE);
	while (tokenizer.hasMoreTokens()) {
	previousExtensions.add(tokenizer.nextToken());
	}
	}

	if (previousExtensions.size() == currentExtensions.size() && previousExtensions.containsAll(currentExtensions))
	return null;

	return currentExtensionsProperty;
	}

	/**
	* Escapes the pipe ('\|') character in a URI using the standard URI escape sequence.
	* This is done because the pipe character is used as the delimiter between locations
	* in the cache extensions profile property.
	*/
	private String escapePipe(String location) {
	String result = location;
	int pipeIndex;
	while ((pipeIndex = result.indexOf(',')) != -1)
	result = result.substring(0, pipeIndex) + "%7C" + result.substring(pipeIndex + 1); //$NON-NLS-1$
	return result;
	}

	public ProfileChangeRequest createProfileChangeRequest(ProvisioningContext context) {
	ProfileChangeRequest request = new ProfileChangeRequest(profile);

	boolean resolve = Boolean.valueOf(profile.getProperty("org.eclipse.equinox.p2.resolve")).booleanValue(); //$NON-NLS-1$
	if (resolve)
	request.removeProfileProperty("org.eclipse.equinox.p2.resolve"); //$NON-NLS-1$

	List<IInstallableUnit> toAdd = new ArrayList<IInstallableUnit>();
	List<IInstallableUnit> toRemove = new ArrayList<IInstallableUnit>();

	boolean foundIUsToAdd = false;
	Set<IInstallableUnit> profileIUs = profile.query(InstallableUnitQuery.ANY, null).unmodifiableSet();

	// we use IProfile.available(...) here so that we also gather any shared IUs
	Set<IInstallableUnit> availableProfileIUs = profile.available(InstallableUnitQuery.ANY, null).unmodifiableSet();

	// get all IUs from all our repos (toAdd)
	IQueryResult<IInstallableUnit> allIUs = getAllIUsFromRepos();
	for (Iterator<IInstallableUnit> iter = allIUs.iterator(); iter.hasNext();) {
	final IInstallableUnit iu = iter.next();
	// if the IU is already installed in the profile then skip it
	if (!profileIUs.contains(iu)) {
	if (GroupQuery.isGroup(iu))
	request.setInstallableUnitProfileProperty(iu, IProfile.PROP_PROFILE_ROOT_IU, Boolean.TRUE.toString());
	// mark all IUs with special property
	request.setInstallableUnitProfileProperty(iu, PROP_FROM_DROPINS, Boolean.TRUE.toString());
	request.setInstallableUnitInclusionRules(iu, PlannerHelper.createOptionalInclusionRule(iu));
	request.setInstallableUnitProfileProperty(iu, IProfile.PROP_PROFILE_LOCKED_IU, Integer.toString(IProfile.LOCK_UNINSTALL));
	toAdd.add(iu);

	// as soon as we find something locally that needs to be installed, then
	// everything from the parent's dropins must be installed locally as well.
	if (!foundIUsToAdd && !availableProfileIUs.contains(iu)) {
	foundIUsToAdd = true;
	}
	}
	}

	// get all IUs from profile with marked property (existing)
	IQueryResult<IInstallableUnit> dropinIUs = profile.query(new IUProfilePropertyQuery(PROP_FROM_DROPINS, Boolean.toString(true)), null);
	Set<IInstallableUnit> all = allIUs.unmodifiableSet();
	for (Iterator<IInstallableUnit> iter = dropinIUs.iterator(); iter.hasNext();) {
	IInstallableUnit iu = iter.next();
	// the STRICT policy is set when we install things via the UI, we use it to differentiate between IUs installed
	// via the dropins and the UI. (dropins are considered optional) If an IU has both properties set it means that
	// it was initially installed via the dropins but then upgraded via the UI. (properties are copied from the old IU
	// to the new IU during an upgrade) In this case we want to remove the "from dropins" property so the upgrade
	// will stick.
	if ("STRICT".equals(profile.getInstallableUnitProperty(iu, "org.eclipse.equinox.p2.internal.inclusion.rules"))) { //$NON-NLS-1$//$NON-NLS-2$
	request.removeInstallableUnitProfileProperty(iu, PROP_FROM_DROPINS);
	request.removeInstallableUnitProfileProperty(iu, IProfile.PROP_PROFILE_LOCKED_IU);
	continue;
	}
	// remove the IUs that are in the intersection between the 2 sets
	if (all.contains(iu))
	toAdd.remove(iu);
	else
	toRemove.add(iu);
	}

	if (!foundIUsToAdd && toRemove.isEmpty() && !resolve) {
	if (Tracing.DEBUG_RECONCILER)
	Tracing.debug("[reconciler] Nothing to do."); //$NON-NLS-1$
	return null;
	}

	context.setExtraIUs(toAdd);
	request.addInstallableUnits(toAdd.toArray(new IInstallableUnit[toAdd.size()]));
	request.removeInstallableUnits(toRemove.toArray(new IInstallableUnit[toRemove.size()]));
	debug(request);
	return request;
	}

	/*
	* If debugging is turned on, then print out the details for the given profile change request.
	*/
	private void debug(ProfileChangeRequest request) {
	if (!Tracing.DEBUG_RECONCILER)
	return;
	final String PREFIX = "[reconciler] "; //$NON-NLS-1$
	IInstallableUnit[] toAdd = request.getAddedInstallableUnits();
	if (toAdd == null \|\| toAdd.length == 0) {
	Tracing.debug(PREFIX + "No installable units to add."); //$NON-NLS-1$
	} else {
	for (int i = 0; i < toAdd.length; i++) {
	Tracing.debug(PREFIX + "Adding IU: " + toAdd[i].getId() + ' ' + toAdd[i].getVersion()); //$NON-NLS-1$
	}
	}
	Map<IInstallableUnit, Map<String, String>> propsToAdd = request.getInstallableUnitProfilePropertiesToAdd();
	if (propsToAdd == null \|\| propsToAdd.isEmpty()) {
	Tracing.debug(PREFIX + "No IU properties to add."); //$NON-NLS-1$
	} else {
	for (Entry<IInstallableUnit, Map<String, String>> entry : propsToAdd.entrySet()) {
	Tracing.debug(PREFIX + "Adding IU property: " + entry.getKey() + "->" + entry.getValue()); //$NON-NLS-1$ //$NON-NLS-2$
	}
	}

	IInstallableUnit[] toRemove = request.getRemovedInstallableUnits();
	if (toRemove == null \|\| toRemove.length == 0) {
	Tracing.debug(PREFIX + "No installable units to remove."); //$NON-NLS-1$
	} else {
	for (int i = 0; i < toRemove.length; i++) {
	Tracing.debug(PREFIX + "Removing IU: " + toRemove[i].getId() + ' ' + toRemove[i].getVersion()); //$NON-NLS-1$
	}
	}
	Map<IInstallableUnit, List<String>> propsToRemove = request.getInstallableUnitProfilePropertiesToRemove();
	if (propsToRemove == null \|\| propsToRemove.isEmpty()) {
	Tracing.debug(PREFIX + "No IU properties to remove."); //$NON-NLS-1$
	} else {
	for (Entry<IInstallableUnit, List<String>> entry : propsToRemove.entrySet()) {
	Tracing.debug(PREFIX + "Removing IU property: " + entry.getKey() + "->" + entry.getValue()); //$NON-NLS-1$ //$NON-NLS-2$
	}
	}
	}

	private IQueryResult<IInstallableUnit> getAllIUsFromRepos() {
	// TODO: Should consider using a sequenced iterator here instead of collecting
	Collector<IInstallableUnit> allRepos = new Collector<IInstallableUnit>();
	for (IMetadataRepository repository : repositoryMap.values()) {
	allRepos.addAll(repository.query(InstallableUnitQuery.ANY, null));
	}
	return allRepos;
	}

	private IProvisioningPlan createProvisioningPlan(ProfileChangeRequest request, ProvisioningContext provisioningContext, IProgressMonitor monitor) {
	BundleContext context = Activator.getContext();
	ServiceReference reference = context.getServiceReference(IPlanner.SERVICE_NAME);
	IPlanner planner = (IPlanner) context.getService(reference);

	try {
	return planner.getProvisioningPlan(request, provisioningContext, monitor);
	} finally {
	context.ungetService(reference);
	}
	}

	private IStatus setProperty(String key, String value, ProvisioningContext provisioningContext, IProgressMonitor monitor) {
	BundleContext context = Activator.getContext();
	ServiceReference reference = context.getServiceReference(IEngine.SERVICE_NAME);
	IEngine engine = (IEngine) context.getService(reference);
	ServiceReference plannerReference = context.getServiceReference(IPlanner.SERVICE_NAME);
	IPlanner planner = (IPlanner) context.getService(reference);
	try {
	ProfileChangeRequest addPropertyRequest = new ProfileChangeRequest(profile);
	addPropertyRequest.setProfileProperty(key, value);
	IProvisioningPlan plan = planner.getProvisioningPlan(addPropertyRequest, provisioningContext, monitor);
	IPhaseSet phaseSet = engine.createPhaseSetExcluding(new String[] {IPhaseSet.PHASE_COLLECT, IPhaseSet.PHASE_CHECK_TRUST});
	return engine.perform(plan, phaseSet, monitor);
	} finally {
	context.ungetService(reference);
	context.ungetService(plannerReference);
	}
	}

	private IStatus executePlan(IProvisioningPlan plan, ProvisioningContext provisioningContext, IProgressMonitor monitor) {
	BundleContext context = Activator.getContext();
	ServiceReference reference = context.getServiceReference(IEngine.SERVICE_NAME);
	IEngine engine = (IEngine) context.getService(reference);
	try {
	IPhaseSet phaseSet = engine.createPhaseSetExcluding(new String[] {IPhaseSet.PHASE_COLLECT, IPhaseSet.PHASE_CHECK_TRUST});

	if (plan.getInstallerPlan() != null) {
	IStatus installerPlanStatus = engine.perform(plan.getInstallerPlan(), phaseSet, monitor);
	if (!installerPlanStatus.isOK())
	return installerPlanStatus;

	applyConfiguration(true);
	}
	return engine.perform(plan, phaseSet, monitor);
	} finally {
	context.ungetService(reference);
	}
	}

	/*
	* Write out the configuration file.
	*/
	private IStatus applyConfiguration(boolean isInstaller) {
	if (!isInstaller && isReconciliationApplicationRunning())
	return Status.OK_STATUS;
	BundleContext context = Activator.getContext();
	ServiceReference reference = context.getServiceReference(Configurator.class.getName());
	Configurator configurator = (Configurator) context.getService(reference);
	try {
	configurator.applyConfiguration();
	} catch (IOException e) {
	return new Status(IStatus.ERROR, Activator.ID, "Unexpected failure applying configuration", e); //$NON-NLS-1$
	} finally {
	context.ungetService(reference);
	}
	return Status.OK_STATUS;
	}

	static boolean isReconciliationApplicationRunning() {
	EnvironmentInfo info = (EnvironmentInfo) ServiceHelper.getService(Activator.getContext(), EnvironmentInfo.class.getName());
	if (info == null)
	return false;
	String[] args = info.getCommandLineArgs();
	if (args == null)
	return false;
	for (int i = 0; i < args.length; i++) {
	if (args[i] != null && RECONCILER_APPLICATION_ID.equals(args[i].trim()))
	return true;
	}
	return false;
	}
	}