bundles/org.eclipse.core.resources/src/org/eclipse/core/internal/refresh/RefreshJob.java - platform/eclipse.platform.resources - Git at Google

 /*******************************************************************************
  *  Copyright (c) 2004, 2015 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 - Initial API and implementation
  *     James Blackburn (Broadcom Corp.) - ongoing development
  *     Lars Vogel <Lars.Vogel@vogella.com> - Bug 473427, 483862
  *******************************************************************************/
 package org.eclipse.core.internal.refresh;

 import java.util.*;
 import org.eclipse.core.internal.localstore.PrefixPool;
 import org.eclipse.core.internal.utils.Messages;
 import org.eclipse.core.internal.utils.Policy;
 import org.eclipse.core.resources.*;
 import org.eclipse.core.runtime.*;

 /**
  * The <code>RefreshJob</code> class maintains a list of resources that
  * need to be refreshed, and periodically schedules itself to perform the
  * refreshes in the background.
  *
  * @since 3.0
  */
 public class RefreshJob extends WorkspaceJob {
 	private static final long UPDATE_DELAY = 200;
 	/**
 	 * List of refresh requests. Requests are processed in order from
 	 * the end of the list. Requests can be added to either the beginning
 	 * or the end of the list depending on whether they are explicit user
 	 * requests or background refresh requests.
 	 */
 	private final List<IResource> fRequests;

 	/**
 	 * The history of path prefixes visited during this refresh job invocation.
 	 * This is used to prevent infinite refresh loops caused by symbolic links in the file system.
 	 */
 	private PrefixPool pathPrefixHistory, rootPathHistory;

 	public RefreshJob() {
 		super(Messages.refresh_jobName);
 		fRequests = new ArrayList<>(1);
 	}

 	/**
 	 * Adds the given resource to the set of resources that need refreshing.
 	 * Synchronized in order to protect the collection during add.
 	 * @param resource
 	 */
 	private synchronized void addRequest(IResource resource) {
 		IPath toAdd = resource.getFullPath();
 		for (Iterator<IResource> it = fRequests.iterator(); it.hasNext();) {
 			IPath request = it.next().getFullPath();
 			//discard any existing requests the same or below the resource to be added
 			if (toAdd.isPrefixOf(request))
 				it.remove();
 			//nothing to do if the resource to be added is a child of an existing request
 			else if (request.isPrefixOf(toAdd))
 				return;
 		}
 		//finally add the new request to the front of the queue
 		fRequests.add(resource);
 	}

 	private synchronized void addRequests(List<IResource> list) {
 		//add requests to the end of the queue
 		fRequests.addAll(0, list);
 	}

 	@Override
 	public boolean belongsTo(Object family) {
 		return family == ResourcesPlugin.FAMILY_AUTO_REFRESH;
 	}

 	/**
 	 * This method adds all members at the specified depth from the resource
 	 * to the provided list.
 	 */
 	private List<IResource> collectChildrenToDepth(IResource resource, ArrayList<IResource> children, int depth) {
 		if (resource.getType() == IResource.FILE)
 			return children;
 		IResource[] members;
 		try {
 			members = ((IContainer) resource).members();
 		} catch (CoreException e) {
 			//resource is not accessible - just return what we have
 			return children;
 		}
 		for (int i = 0; i < members.length; i++) {
 			if (members[i].getType() == IResource.FILE)
 				continue;
 			if (depth <= 1)
 				children.add(members[i]);
 			else
 				collectChildrenToDepth(members[i], children, depth - 1);
 		}
 		return children;
 	}

 	/**
 	 * Returns the path prefixes visited by this job so far.
 	 */
 	public PrefixPool getPathPrefixHistory() {
 		if (pathPrefixHistory == null)
 			pathPrefixHistory = new PrefixPool(20);
 		return pathPrefixHistory;
 	}

 	/**
 	 * Returns the root paths visited by this job so far.
 	 */
 	public PrefixPool getRootPathHistory() {
 		if (rootPathHistory == null)
 			rootPathHistory = new PrefixPool(20);
 		return rootPathHistory;
 	}

 	/**
 	 * Returns the next item to refresh, or <code>null</code> if there are no requests
 	 */
 	private synchronized IResource nextRequest() {
 		// synchronized: in order to atomically obtain and clear requests
 		int len = fRequests.size();
 		if (len == 0)
 			return null;
 		return fRequests.remove(len - 1);
 	}

 	/**
 	 * @see org.eclipse.core.resources.refresh.IRefreshResult#refresh
 	 */
 	public void refresh(IResource resource) {
 		if (resource == null)
 			return;
 		addRequest(resource);
 		schedule(UPDATE_DELAY);
 	}

 	@Override
 	public IStatus runInWorkspace(IProgressMonitor monitor) {
 		long start = System.currentTimeMillis();
 		String msg = Messages.refresh_refreshErr;
 		MultiStatus errors = new MultiStatus(ResourcesPlugin.PI_RESOURCES, 1, msg, null);
 		long longestRefresh = 0;
 		SubMonitor subMonitor = SubMonitor.convert(monitor);
 		try {
 			if (Policy.DEBUG_AUTO_REFRESH)
 				Policy.debug(RefreshManager.DEBUG_PREFIX + " starting refresh job"); //$NON-NLS-1$
 			int refreshCount = 0;
 			int depth = 2;

 			IResource toRefresh;
 			while ((toRefresh = nextRequest()) != null) {
 				try {
 					subMonitor.setWorkRemaining(Math.max(fRequests.size(), 100));
 					refreshCount++;
 					long refreshTime = -System.currentTimeMillis();
 					toRefresh.refreshLocal(1000 + depth, subMonitor.split(1));
 					refreshTime += System.currentTimeMillis();
 					if (refreshTime > longestRefresh)
 						longestRefresh = refreshTime;
 					//show occasional progress
 					if (refreshCount % 1000 == 0) {
 						//be polite to other threads (no effect on some platforms)
 						Thread.yield();
 						//throttle depth if it takes too long
 						if (longestRefresh > 2000 && depth > 1) {
 							depth = 1;
 						}
 						if (longestRefresh < 1000) {
 							depth *= 2;
 						}
 						longestRefresh = 0;
 					}
 					addRequests(collectChildrenToDepth(toRefresh, new ArrayList<IResource>(), depth));
 				} catch (CoreException e) {
 					errors.merge(new Status(IStatus.ERROR, ResourcesPlugin.PI_RESOURCES, 1, errors.getMessage(), e));
 				}
 			}
 		} finally {
 			pathPrefixHistory = null;
 			rootPathHistory = null;
 			if (Policy.DEBUG_AUTO_REFRESH)
 				Policy.debug(RefreshManager.DEBUG_PREFIX + " finished refresh job in: " + (System.currentTimeMillis() - start) + "ms"); //$NON-NLS-1$ //$NON-NLS-2$
 		}
 		if (!errors.isOK())
 			return errors;
 		return Status.OK_STATUS;
 	}

 	@Override
 	public synchronized boolean shouldRun() {
 		return !fRequests.isEmpty();
 	}

 	/**
 	 * Starts the refresh job
 	 */
 	public void start() {
 		if (Policy.DEBUG_AUTO_REFRESH)
 			Policy.debug(RefreshManager.DEBUG_PREFIX + " enabling auto-refresh"); //$NON-NLS-1$
 	}

 	/**
 	 * Stops the refresh job
 	 */
 	public void stop() {
 		if (Policy.DEBUG_AUTO_REFRESH)
 			Policy.debug(RefreshManager.DEBUG_PREFIX + " disabling auto-refresh"); //$NON-NLS-1$
 		cancel();
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2004, 2015 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 - Initial API and implementation
	* James Blackburn (Broadcom Corp.) - ongoing development
	* Lars Vogel <Lars.Vogel@vogella.com> - Bug 473427, 483862
	*******************************************************************************/
	package org.eclipse.core.internal.refresh;

	import java.util.*;
	import org.eclipse.core.internal.localstore.PrefixPool;
	import org.eclipse.core.internal.utils.Messages;
	import org.eclipse.core.internal.utils.Policy;
	import org.eclipse.core.resources.*;
	import org.eclipse.core.runtime.*;

	/**
	* The <code>RefreshJob</code> class maintains a list of resources that
	* need to be refreshed, and periodically schedules itself to perform the
	* refreshes in the background.
	*
	* @since 3.0
	*/
	public class RefreshJob extends WorkspaceJob {
	private static final long UPDATE_DELAY = 200;
	/**
	* List of refresh requests. Requests are processed in order from
	* the end of the list. Requests can be added to either the beginning
	* or the end of the list depending on whether they are explicit user
	* requests or background refresh requests.
	*/
	private final List<IResource> fRequests;

	/**
	* The history of path prefixes visited during this refresh job invocation.
	* This is used to prevent infinite refresh loops caused by symbolic links in the file system.
	*/
	private PrefixPool pathPrefixHistory, rootPathHistory;

	public RefreshJob() {
	super(Messages.refresh_jobName);
	fRequests = new ArrayList<>(1);
	}

	/**
	* Adds the given resource to the set of resources that need refreshing.
	* Synchronized in order to protect the collection during add.
	* @param resource
	*/
	private synchronized void addRequest(IResource resource) {
	IPath toAdd = resource.getFullPath();
	for (Iterator<IResource> it = fRequests.iterator(); it.hasNext();) {
	IPath request = it.next().getFullPath();
	//discard any existing requests the same or below the resource to be added
	if (toAdd.isPrefixOf(request))
	it.remove();
	//nothing to do if the resource to be added is a child of an existing request
	else if (request.isPrefixOf(toAdd))
	return;
	}
	//finally add the new request to the front of the queue
	fRequests.add(resource);
	}

	private synchronized void addRequests(List<IResource> list) {
	//add requests to the end of the queue
	fRequests.addAll(0, list);
	}

	@Override
	public boolean belongsTo(Object family) {
	return family == ResourcesPlugin.FAMILY_AUTO_REFRESH;
	}

	/**
	* This method adds all members at the specified depth from the resource
	* to the provided list.
	*/
	private List<IResource> collectChildrenToDepth(IResource resource, ArrayList<IResource> children, int depth) {
	if (resource.getType() == IResource.FILE)
	return children;
	IResource[] members;
	try {
	members = ((IContainer) resource).members();
	} catch (CoreException e) {
	//resource is not accessible - just return what we have
	return children;
	}
	for (int i = 0; i < members.length; i++) {
	if (members[i].getType() == IResource.FILE)
	continue;
	if (depth <= 1)
	children.add(members[i]);
	else
	collectChildrenToDepth(members[i], children, depth - 1);
	}
	return children;
	}

	/**
	* Returns the path prefixes visited by this job so far.
	*/
	public PrefixPool getPathPrefixHistory() {
	if (pathPrefixHistory == null)
	pathPrefixHistory = new PrefixPool(20);
	return pathPrefixHistory;
	}

	/**
	* Returns the root paths visited by this job so far.
	*/
	public PrefixPool getRootPathHistory() {
	if (rootPathHistory == null)
	rootPathHistory = new PrefixPool(20);
	return rootPathHistory;
	}

	/**
	* Returns the next item to refresh, or <code>null</code> if there are no requests
	*/
	private synchronized IResource nextRequest() {
	// synchronized: in order to atomically obtain and clear requests
	int len = fRequests.size();
	if (len == 0)
	return null;
	return fRequests.remove(len - 1);
	}

	/**
	* @see org.eclipse.core.resources.refresh.IRefreshResult#refresh
	*/
	public void refresh(IResource resource) {
	if (resource == null)
	return;
	addRequest(resource);
	schedule(UPDATE_DELAY);
	}

	@Override
	public IStatus runInWorkspace(IProgressMonitor monitor) {
	long start = System.currentTimeMillis();
	String msg = Messages.refresh_refreshErr;
	MultiStatus errors = new MultiStatus(ResourcesPlugin.PI_RESOURCES, 1, msg, null);
	long longestRefresh = 0;
	SubMonitor subMonitor = SubMonitor.convert(monitor);
	try {
	if (Policy.DEBUG_AUTO_REFRESH)
	Policy.debug(RefreshManager.DEBUG_PREFIX + " starting refresh job"); //$NON-NLS-1$
	int refreshCount = 0;
	int depth = 2;

	IResource toRefresh;
	while ((toRefresh = nextRequest()) != null) {
	try {
	subMonitor.setWorkRemaining(Math.max(fRequests.size(), 100));
	refreshCount++;
	long refreshTime = -System.currentTimeMillis();
	toRefresh.refreshLocal(1000 + depth, subMonitor.split(1));
	refreshTime += System.currentTimeMillis();
	if (refreshTime > longestRefresh)
	longestRefresh = refreshTime;
	//show occasional progress
	if (refreshCount % 1000 == 0) {
	//be polite to other threads (no effect on some platforms)
	Thread.yield();
	//throttle depth if it takes too long
	if (longestRefresh > 2000 && depth > 1) {
	depth = 1;
	}
	if (longestRefresh < 1000) {
	depth *= 2;
	}
	longestRefresh = 0;
	}
	addRequests(collectChildrenToDepth(toRefresh, new ArrayList<IResource>(), depth));
	} catch (CoreException e) {
	errors.merge(new Status(IStatus.ERROR, ResourcesPlugin.PI_RESOURCES, 1, errors.getMessage(), e));
	}
	}
	} finally {
	pathPrefixHistory = null;
	rootPathHistory = null;
	if (Policy.DEBUG_AUTO_REFRESH)
	Policy.debug(RefreshManager.DEBUG_PREFIX + " finished refresh job in: " + (System.currentTimeMillis() - start) + "ms"); //$NON-NLS-1$ //$NON-NLS-2$
	}
	if (!errors.isOK())
	return errors;
	return Status.OK_STATUS;
	}

	@Override
	public synchronized boolean shouldRun() {
	return !fRequests.isEmpty();
	}

	/**
	* Starts the refresh job
	*/
	public void start() {
	if (Policy.DEBUG_AUTO_REFRESH)
	Policy.debug(RefreshManager.DEBUG_PREFIX + " enabling auto-refresh"); //$NON-NLS-1$
	}

	/**
	* Stops the refresh job
	*/
	public void stop() {
	if (Policy.DEBUG_AUTO_REFRESH)
	Policy.debug(RefreshManager.DEBUG_PREFIX + " disabling auto-refresh"); //$NON-NLS-1$
	cancel();
	}
	}