org.eclipse.m2e.wtp/src/org/eclipse/m2e/wtp/internal/filtering/ResourceFilteringBuildParticipant.java - m2e-wtp/org.eclipse.m2e.wtp - Git at Google

 /*******************************************************************************
  * Copyright (c) 2008-2014 Sonatype, Inc.
  * 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
  *******************************************************************************/

 package org.eclipse.m2e.wtp.internal.filtering;


 import java.io.File;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.util.Collections;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Set;

 import org.apache.maven.execution.MavenExecutionRequest;
 import org.apache.maven.execution.MavenSession;
 import org.apache.maven.lifecycle.MavenExecutionPlan;
 import org.apache.maven.plugin.MojoExecution;
 import org.apache.maven.project.MavenProject;
 import org.codehaus.plexus.util.Scanner;
 import org.codehaus.plexus.util.StringUtils;
 import org.codehaus.plexus.util.xml.Xpp3Dom;
 import org.codehaus.plexus.util.xml.Xpp3DomUtils;
 import org.eclipse.core.resources.IContainer;
 import org.eclipse.core.resources.IFolder;
 import org.eclipse.core.resources.IMarker;
 import org.eclipse.core.resources.IProject;
 import org.eclipse.core.resources.IResource;
 import org.eclipse.core.resources.IResourceDelta;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IPath;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.core.runtime.NullProgressMonitor;
 import org.eclipse.core.runtime.Path;
 import org.eclipse.m2e.core.MavenPlugin;
 import org.eclipse.m2e.core.embedder.IMaven;
 import org.eclipse.m2e.core.internal.MavenPluginActivator;
 import org.eclipse.m2e.core.project.IMavenProjectFacade;
 import org.eclipse.m2e.core.project.IMavenProjectRegistry;
 import org.eclipse.m2e.core.project.ResolverConfiguration;
 import org.eclipse.m2e.core.project.configurator.AbstractBuildParticipant;
 import org.eclipse.m2e.wtp.DomUtils;
 import org.eclipse.m2e.wtp.MavenWtpConstants;
 import org.eclipse.m2e.wtp.WTPProjectsUtil;
 import org.eclipse.m2e.wtp.internal.Messages;
 import org.eclipse.osgi.util.NLS;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.sonatype.plexus.build.incremental.BuildContext;
 import org.sonatype.plexus.build.incremental.ThreadBuildContext;

 /**
  * ResourceFilteringBuildParticipant
  *
  * @author Fred Bricon
  */
 @SuppressWarnings("restriction")
 public class ResourceFilteringBuildParticipant extends AbstractBuildParticipant {

   private static final Logger LOG = LoggerFactory.getLogger(ResourceFilteringBuildParticipant.class );

   private CleanBuildContext forceCopyBuildContext;

   @Override
   public Set<IProject> build(int kind, IProgressMonitor monitor) throws Exception {
     IMavenProjectFacade facade = getMavenProjectFacade();
     ResourceFilteringConfiguration configuration = ResourceFilteringConfigurationFactory.getConfiguration(facade);
     List<Xpp3Dom> resources = null;
     if (configuration == null || (resources = configuration.getResources()) == null) {
       //Nothing to filter
       return null;
     }

     IProject project = facade.getProject();
     //FIXME assuming path relative to current project
     IPath targetFolder = configuration.getTargetFolder();
     IResourceDelta delta = getDelta(project);

     BuildContext oldBuildContext = ThreadBuildContext.getContext();

     try {
       forceCopyBuildContext = null;
       List<String> filters = configuration.getFilters();
       if (!project.getFolder(targetFolder).exists() || changeRequiresForcedCopy(facade, filters, delta)) {
         LOG.info(NLS.bind(Messages.ResourceFilteringBuildParticipant_Changed_Resources_Require_Clean_Build,project.getName()));
         //String id = "" + "-" + getClass().getName();
         forceCopyBuildContext = new CleanBuildContext(oldBuildContext);
         ThreadBuildContext.setThreadBuildContext(forceCopyBuildContext);
       }
       if (forceCopyBuildContext != null || hasResourcesChanged(facade, delta, resources)) {
         LOG.info(NLS.bind(Messages.ResourceFilteringBuildParticipant_Executing_Resource_Filtering,project.getName()));
         executeCopyResources(facade, configuration, targetFolder, resources, monitor);
         //FIXME deal with absolute paths
         IFolder destFolder = project.getFolder(targetFolder);
         if (destFolder.exists()){
           destFolder.refreshLocal(IResource.DEPTH_INFINITE, monitor);
         }
       }
     } finally {
       ThreadBuildContext.setThreadBuildContext(oldBuildContext);
     }

     return null;
   }

   @Override
   protected BuildContext getBuildContext() {
      return (forceCopyBuildContext == null)?super.getBuildContext() : forceCopyBuildContext;
   }

    /**
   * If the pom.xml or any of the project's filters were changed, a forced copy is required
   * @param facade
   * @param delta
   * @return
   */
    private boolean changeRequiresForcedCopy(IMavenProjectFacade facade, List<String> filters, IResourceDelta delta) {
      if (delta == null) {
        return false;
      }

      if (delta.findMember(facade.getPom().getProjectRelativePath()) != null ) {
        return true;
      }

      for (String filter : filters) {
        IPath filterPath = facade.getProjectRelativePath(filter);
        if (filterPath == null) {
          filterPath =Path.fromOSString(filter);
        }
        if (delta.findMember(filterPath) != null){
          return true;
        }
      }
      return false;

    }

   @Override
 public void clean(IProgressMonitor monitor) throws CoreException {
     IMavenProjectFacade facade = getMavenProjectFacade();
     ResourceFilteringConfiguration configuration = ResourceFilteringConfigurationFactory.getConfiguration(facade);
     if (configuration == null) {
       //Nothing to do
       return;
     }

     IProject project = facade.getProject();
     IPath targetFolderPath = configuration.getTargetFolder();
     deleteFilteredResources(project, targetFolderPath);
     super.clean(monitor);
   }

   private void deleteFilteredResources(IProject project, IPath targetFolderPath) throws CoreException {
     IFolder targetFolder = project.getFolder(targetFolderPath);
     if (targetFolder.exists()) {
       IContainer parent = targetFolder.getParent();
       LOG.info(NLS.bind(Messages.ResourceFilteringBuildParticipant_Cleaning_Filtered_Folder,project.getName()));
       IProgressMonitor monitor =new NullProgressMonitor();
       targetFolder.delete(true, monitor);
       if (parent != null) {
         parent.refreshLocal(IResource.DEPTH_INFINITE, monitor );
       }
     }
   }


   /**
    * @param mavenProject
    * @param iResourceDelta
    * @param resources
    * @return
    */
   private boolean hasResourcesChanged(IMavenProjectFacade facade, IResourceDelta delta, List<Xpp3Dom> resources) {
     if (resources == null || resources.isEmpty()){
       return false;
     }

     Set<IPath> resourcePaths = getResourcePaths(facade, resources);

     if(delta == null) {
       return !resourcePaths.isEmpty();
     }

     for(IPath resourcePath : resourcePaths) {
       IResourceDelta member = delta.findMember(resourcePath);
       //XXX deal with member kind/flags
       if(member != null) {
           return true;
           //we need to deal with superceded resources on the maven level
       }
     }

     return false;
   }


   private Set<IPath> getResourcePaths(IMavenProjectFacade facade, List<Xpp3Dom> resources) {
     Set<IPath> resourcePaths = new LinkedHashSet<>();
     for(Xpp3Dom resource : resources) {
       IPath folder= null;
       Xpp3Dom xpp3Directory = resource.getChild("directory"); //$NON-NLS-1$
       if (xpp3Directory != null)
       {
         String dir = xpp3Directory.getValue();
         if (StringUtils.isNotEmpty(dir)){
           folder = WTPProjectsUtil.tryProjectRelativePath(facade.getProject(), dir);
         }
       }
       if(folder != null && !folder.isEmpty()) {
         resourcePaths.add(folder);
       }
     }

     return resourcePaths;
   }


   private void executeCopyResources(IMavenProjectFacade facade,  ResourceFilteringConfiguration filteringConfiguration, IPath targetFolder, List<Xpp3Dom> resources, IProgressMonitor monitor) throws CoreException {

     //Create a maven request + session
     ResolverConfiguration resolverConfig = facade.getResolverConfiguration();

     List<String> filters = filteringConfiguration.getFilters();
     IMavenProjectRegistry projectManager = MavenPlugin.getMavenProjectRegistry();
     MavenExecutionRequest request = projectManager.createExecutionRequest(facade.getPom(), resolverConfig, monitor);
     request.setRecursive(false);
     request.setOffline(true);

     IMaven maven = MavenPlugin.getMaven();
     MavenProject mavenProject = facade.getMavenProject();

     MavenSession session = maven.createSession(request, mavenProject);
     MavenExecutionPlan executionPlan = maven.calculateExecutionPlan(session, mavenProject, Collections.singletonList("resources:copy-resources"), true, monitor); //$NON-NLS-1$

     MojoExecution copyFilteredResourcesMojo = getExecution(executionPlan, "maven-resources-plugin"); //$NON-NLS-1$

     if (copyFilteredResourcesMojo == null) return;

     Xpp3Dom originalConfig = copyFilteredResourcesMojo.getConfiguration();
     Xpp3Dom  configuration = Xpp3DomUtils.mergeXpp3Dom(new Xpp3Dom("configuration"), originalConfig); //$NON-NLS-1$
     boolean parentHierarchyLoaded = false;
     try {
       parentHierarchyLoaded = loadParentHierarchy(facade, monitor);

       //Set resource directories to read
       setupResources(configuration, resources);

       //Force overwrite
       setValue(configuration, "overwrite", Boolean.TRUE); //$NON-NLS-1$

       //Limit placeholder delimiters, otherwise, pages containing @ wouldn't be filtered correctly
       setupDelimiters(configuration);

       //Set output directory to the m2eclipse-wtp webresources directory
       setValue(configuration, "outputDirectory", targetFolder.toPortableString()); //$NON-NLS-1$

       setValue(configuration, "escapeString", filteringConfiguration.getEscapeString()); //$NON-NLS-1$

       setNonfilteredExtensions(configuration, filteringConfiguration.getNonfilteredExtensions());

       //Setup filters
       setupFilters(configuration, filters);

       //Create a maven request + session
       request.setRecursive(false);
       request.setOffline(true);

       //Execute our modified mojo
       copyFilteredResourcesMojo.setConfiguration(configuration);
       copyFilteredResourcesMojo.getMojoDescriptor().setGoal("copy-resources"); //$NON-NLS-1$

       maven.execute(session, copyFilteredResourcesMojo, monitor);

       if (session.getResult().hasExceptions()){

           MavenPluginActivator.getDefault().getMavenMarkerManager().addMarker(facade.getProject(), MavenWtpConstants.WTP_MARKER_FILTERING_ERROR,Messages.ResourceFilteringBuildParticipant_Error_While_Filtering_Resources, -1,  IMarker.SEVERITY_ERROR);
           //move exceptions up to the original session, so they can be handled by the maven builder
           //XXX current exceptions refer to maven-resource-plugin (since that's what we used), we should probably
           // throw a new exception instead to indicate the problem(s) come(s) from web resource filtering
           for(Throwable t : session.getResult().getExceptions())
           {
             getSession().getResult().addException(t);
           }
       }

     } finally {
       //Restore original configuration
       copyFilteredResourcesMojo.setConfiguration(originalConfig);
       if (parentHierarchyLoaded) {
         mavenProject.setParent(null);
       }
     }
   }

   /**
    * @param configuration
    * @param extensions
    */
   private void setNonfilteredExtensions(Xpp3Dom configuration, List<Xpp3Dom> extensions) {
     if (extensions == null || extensions.isEmpty()) {
       return;
     }
     Xpp3Dom nonFilteredFileExtensionsNode = configuration.getChild("nonFilteredFileExtensions"); //$NON-NLS-1$
     if (nonFilteredFileExtensionsNode == null) {
       nonFilteredFileExtensionsNode = new Xpp3Dom("nonFilteredFileExtensions"); //$NON-NLS-1$
       configuration.addChild(nonFilteredFileExtensionsNode);
     } else {
       DomUtils.removeChildren(nonFilteredFileExtensionsNode);
     }

     for (Xpp3Dom ext : extensions) {
       nonFilteredFileExtensionsNode.addChild(ext);
     }
   }

   private void setValue(Xpp3Dom configuration, String childName, Object value) {
     Xpp3Dom  childNode = configuration.getChild(childName);
     if (childNode==null){
       childNode = new Xpp3Dom(childName);
       configuration.addChild(childNode);
     }
     childNode.setValue((value == null)?null:value.toString());
   }

   private void setupFilters(Xpp3Dom configuration, List<String> filters) {
     if (!filters.isEmpty()) {
       Xpp3Dom  filtersNode = configuration.getChild("filters"); //$NON-NLS-1$

       if (filtersNode==null){
         filtersNode = new Xpp3Dom("filters"); //$NON-NLS-1$
         configuration.addChild(filtersNode);
       } else {
         DomUtils.removeChildren(filtersNode);
       }

       for (String filter : filters) {
         Xpp3Dom filterNode = new Xpp3Dom("filter"); //$NON-NLS-1$
         //Workaround : when run via the BuildParticipant, the maven-resource-plugin won't
         //find a filter defined with a relative path, so we turn it into an absolute one
         IPath filterPath = new Path(filter);
         boolean isAbsolute = false;
         if (filter.startsWith("${basedir}") ||filter.startsWith("/") || filterPath.getDevice() != null) { //$NON-NLS-1$ //$NON-NLS-2$
           isAbsolute = true;
         }
         String filterAbsolutePath;
         if (isAbsolute) {
           filterAbsolutePath = filter;
         } else {
           filterAbsolutePath = "${basedir}/"+filter; //$NON-NLS-1$
         }

         filterNode.setValue(filterAbsolutePath);
         filtersNode.addChild(filterNode );
       }
     }
   }

   private void setupDelimiters(Xpp3Dom configuration) {
     Xpp3Dom  useDefaultDelimitersNode = configuration.getChild("useDefaultDelimiters"); //$NON-NLS-1$
     if (useDefaultDelimitersNode==null){
       useDefaultDelimitersNode = new Xpp3Dom("useDefaultDelimiters"); //$NON-NLS-1$
       configuration.addChild(useDefaultDelimitersNode);
     }
     useDefaultDelimitersNode.setValue(Boolean.FALSE.toString());

     Xpp3Dom  delimitersNode = configuration.getChild("delimiters"); //$NON-NLS-1$
     if (delimitersNode==null){
       delimitersNode = new Xpp3Dom("delimiters"); //$NON-NLS-1$
       configuration.addChild(delimitersNode);
     } else {
       DomUtils.removeChildren(delimitersNode);
     }
     Xpp3Dom delimiter = new Xpp3Dom("delimiter"); //$NON-NLS-1$
     delimiter.setValue("${*}"); //$NON-NLS-1$
     delimitersNode.addChild(delimiter);
   }


   private void setupResources(Xpp3Dom configuration, List<Xpp3Dom> resources) {
     Xpp3Dom  resourcesNode = configuration.getChild("resources"); //$NON-NLS-1$
     if (resourcesNode==null){
       resourcesNode = new Xpp3Dom("resources"); //$NON-NLS-1$
       configuration.addChild(resourcesNode);
     } else {
       resourcesNode.setAttribute("default-value", ""); //$NON-NLS-1$ //$NON-NLS-2$
       DomUtils.removeChildren(resourcesNode);
     }
     for (Xpp3Dom resource : resources)
     {
       resourcesNode.addChild(resource);
     }
   }

   private MojoExecution getExecution(MavenExecutionPlan executionPlan, String artifactId) {
     if (executionPlan == null) return null;
     for(MojoExecution execution : executionPlan.getMojoExecutions()) {
       if(artifactId.equals(execution.getArtifactId()) ) {
         return execution;
       }
     }
     return null;
   }

   /**
    * Workaround for https://bugs.eclipse.org/bugs/show_bug.cgi?id=356725.
    * Loads the parent project hierarchy if needed.
    * @param facade
    * @param monitor
    * @return true if parent projects had to be loaded.
    * @throws CoreException
    */
   private boolean loadParentHierarchy(IMavenProjectFacade facade, IProgressMonitor monitor) throws CoreException {
     boolean loadedParent = false;
     MavenProject mavenProject = facade.getMavenProject();
     try {
       if (mavenProject.getModel().getParent() == null || mavenProject.getParent() != null) {
         //If the method is called without error, we can assume the project has been fully loaded
         //No need to continue.
         return false;
       }
     } catch (IllegalStateException e) {
     //The parent can not be loaded properly
     }
     MavenExecutionRequest request = null;
     while(mavenProject !=null && mavenProject.getModel().getParent() != null) {
         if(monitor.isCanceled()) {
           break;
         }
         if (request == null) {
           request = MavenPlugin.getMavenProjectRegistry().createExecutionRequest(facade, monitor);
         }
         MavenProject parentProject = MavenPlugin.getMaven().resolveParentProject(request, mavenProject, monitor);
         if (parentProject != null) {
           mavenProject.setParent(parentProject);
           loadedParent = true;
         }
         mavenProject = parentProject;
     }
     return loadedParent;
   }


   private static class CleanBuildContext implements BuildContext {

 	private BuildContext originalContext;

 	CleanBuildContext(BuildContext originalContext) {
 		this.originalContext = originalContext;
 	}

 	public boolean hasDelta(String relpath) {
 		return true;
 	}

 	public boolean hasDelta(File file) {
 		return true;
 	}

 	public boolean hasDelta(List relpaths) {
 		return true;
 	}

 	public void refresh(File file) {
 		originalContext.refresh(file);
 	}

 	public OutputStream newFileOutputStream(File file) throws IOException {
 		return originalContext.newFileOutputStream(file);
 	}

 	public Scanner newScanner(File basedir) {
 		return originalContext.newScanner(basedir);
 	}

 	public Scanner newDeleteScanner(File basedir) {
 		return originalContext.newDeleteScanner(basedir);
 	}

 	public Scanner newScanner(File basedir, boolean ignoreDelta) {
 		return originalContext.newScanner(basedir, ignoreDelta);
 	}

 	public boolean isIncremental() {
 		return false;
 	}

 	public void setValue(String key, Object value) {
 		originalContext.setValue(key, value);
 	}

 	public Object getValue(String key) {
 		return originalContext.getValue(key);
 	}

 	public void addWarning(File file, int line, int column, String message,
 			Throwable cause) {
 		originalContext.addWarning(file, line, column, message, cause);
 	}

 	public void addError(File file, int line, int column, String message,
 			Throwable cause) {
 		originalContext.addError(file, line, column, message, cause);
 	}

 	public void addMessage(File file, int line, int column, String message,
 			int severity, Throwable cause) {
 		originalContext.addMessage(file, line, column, message, severity, cause);
 	}

 	public void removeMessages(File file) {
 		originalContext.removeMessages(file);
 	}

 	public boolean isUptodate(File target, File source) {
 		return false;
 	}

   }
 }
	/*******************************************************************************
	* Copyright (c) 2008-2014 Sonatype, Inc.
	* 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
	*******************************************************************************/

	package org.eclipse.m2e.wtp.internal.filtering;


	import java.io.File;
	import java.io.IOException;
	import java.io.OutputStream;
	import java.util.Collections;
	import java.util.LinkedHashSet;
	import java.util.List;
	import java.util.Set;

	import org.apache.maven.execution.MavenExecutionRequest;
	import org.apache.maven.execution.MavenSession;
	import org.apache.maven.lifecycle.MavenExecutionPlan;
	import org.apache.maven.plugin.MojoExecution;
	import org.apache.maven.project.MavenProject;
	import org.codehaus.plexus.util.Scanner;
	import org.codehaus.plexus.util.StringUtils;
	import org.codehaus.plexus.util.xml.Xpp3Dom;
	import org.codehaus.plexus.util.xml.Xpp3DomUtils;
	import org.eclipse.core.resources.IContainer;
	import org.eclipse.core.resources.IFolder;
	import org.eclipse.core.resources.IMarker;
	import org.eclipse.core.resources.IProject;
	import org.eclipse.core.resources.IResource;
	import org.eclipse.core.resources.IResourceDelta;
	import org.eclipse.core.runtime.CoreException;
	import org.eclipse.core.runtime.IPath;
	import org.eclipse.core.runtime.IProgressMonitor;
	import org.eclipse.core.runtime.NullProgressMonitor;
	import org.eclipse.core.runtime.Path;
	import org.eclipse.m2e.core.MavenPlugin;
	import org.eclipse.m2e.core.embedder.IMaven;
	import org.eclipse.m2e.core.internal.MavenPluginActivator;
	import org.eclipse.m2e.core.project.IMavenProjectFacade;
	import org.eclipse.m2e.core.project.IMavenProjectRegistry;
	import org.eclipse.m2e.core.project.ResolverConfiguration;
	import org.eclipse.m2e.core.project.configurator.AbstractBuildParticipant;
	import org.eclipse.m2e.wtp.DomUtils;
	import org.eclipse.m2e.wtp.MavenWtpConstants;
	import org.eclipse.m2e.wtp.WTPProjectsUtil;
	import org.eclipse.m2e.wtp.internal.Messages;
	import org.eclipse.osgi.util.NLS;
	import org.slf4j.Logger;
	import org.slf4j.LoggerFactory;
	import org.sonatype.plexus.build.incremental.BuildContext;
	import org.sonatype.plexus.build.incremental.ThreadBuildContext;

	/**
	* ResourceFilteringBuildParticipant
	*
	* @author Fred Bricon
	*/
	@SuppressWarnings("restriction")
	public class ResourceFilteringBuildParticipant extends AbstractBuildParticipant {

	private static final Logger LOG = LoggerFactory.getLogger(ResourceFilteringBuildParticipant.class );

	private CleanBuildContext forceCopyBuildContext;

	@Override
	public Set<IProject> build(int kind, IProgressMonitor monitor) throws Exception {
	IMavenProjectFacade facade = getMavenProjectFacade();
	ResourceFilteringConfiguration configuration = ResourceFilteringConfigurationFactory.getConfiguration(facade);
	List<Xpp3Dom> resources = null;
	if (configuration == null \|\| (resources = configuration.getResources()) == null) {
	//Nothing to filter
	return null;
	}

	IProject project = facade.getProject();
	//FIXME assuming path relative to current project
	IPath targetFolder = configuration.getTargetFolder();
	IResourceDelta delta = getDelta(project);

	BuildContext oldBuildContext = ThreadBuildContext.getContext();

	try {
	forceCopyBuildContext = null;
	List<String> filters = configuration.getFilters();
	if (!project.getFolder(targetFolder).exists() \|\| changeRequiresForcedCopy(facade, filters, delta)) {
	LOG.info(NLS.bind(Messages.ResourceFilteringBuildParticipant_Changed_Resources_Require_Clean_Build,project.getName()));
	//String id = "" + "-" + getClass().getName();
	forceCopyBuildContext = new CleanBuildContext(oldBuildContext);
	ThreadBuildContext.setThreadBuildContext(forceCopyBuildContext);
	}
	if (forceCopyBuildContext != null \|\| hasResourcesChanged(facade, delta, resources)) {
	LOG.info(NLS.bind(Messages.ResourceFilteringBuildParticipant_Executing_Resource_Filtering,project.getName()));
	executeCopyResources(facade, configuration, targetFolder, resources, monitor);
	//FIXME deal with absolute paths
	IFolder destFolder = project.getFolder(targetFolder);
	if (destFolder.exists()){
	destFolder.refreshLocal(IResource.DEPTH_INFINITE, monitor);
	}
	}
	} finally {
	ThreadBuildContext.setThreadBuildContext(oldBuildContext);
	}

	return null;
	}

	@Override
	protected BuildContext getBuildContext() {
	return (forceCopyBuildContext == null)?super.getBuildContext() : forceCopyBuildContext;
	}

	/**
	* If the pom.xml or any of the project's filters were changed, a forced copy is required
	* @param facade
	* @param delta
	* @return
	*/
	private boolean changeRequiresForcedCopy(IMavenProjectFacade facade, List<String> filters, IResourceDelta delta) {
	if (delta == null) {
	return false;
	}

	if (delta.findMember(facade.getPom().getProjectRelativePath()) != null ) {
	return true;
	}

	for (String filter : filters) {
	IPath filterPath = facade.getProjectRelativePath(filter);
	if (filterPath == null) {
	filterPath =Path.fromOSString(filter);
	}
	if (delta.findMember(filterPath) != null){
	return true;
	}
	}
	return false;

	}

	@Override
	public void clean(IProgressMonitor monitor) throws CoreException {
	IMavenProjectFacade facade = getMavenProjectFacade();
	ResourceFilteringConfiguration configuration = ResourceFilteringConfigurationFactory.getConfiguration(facade);
	if (configuration == null) {
	//Nothing to do
	return;
	}

	IProject project = facade.getProject();
	IPath targetFolderPath = configuration.getTargetFolder();
	deleteFilteredResources(project, targetFolderPath);
	super.clean(monitor);
	}

	private void deleteFilteredResources(IProject project, IPath targetFolderPath) throws CoreException {
	IFolder targetFolder = project.getFolder(targetFolderPath);
	if (targetFolder.exists()) {
	IContainer parent = targetFolder.getParent();
	LOG.info(NLS.bind(Messages.ResourceFilteringBuildParticipant_Cleaning_Filtered_Folder,project.getName()));
	IProgressMonitor monitor =new NullProgressMonitor();
	targetFolder.delete(true, monitor);
	if (parent != null) {
	parent.refreshLocal(IResource.DEPTH_INFINITE, monitor );
	}
	}
	}


	/**
	* @param mavenProject
	* @param iResourceDelta
	* @param resources
	* @return
	*/
	private boolean hasResourcesChanged(IMavenProjectFacade facade, IResourceDelta delta, List<Xpp3Dom> resources) {
	if (resources == null \|\| resources.isEmpty()){
	return false;
	}

	Set<IPath> resourcePaths = getResourcePaths(facade, resources);

	if(delta == null) {
	return !resourcePaths.isEmpty();
	}

	for(IPath resourcePath : resourcePaths) {
	IResourceDelta member = delta.findMember(resourcePath);
	//XXX deal with member kind/flags
	if(member != null) {
	return true;
	//we need to deal with superceded resources on the maven level
	}
	}

	return false;
	}


	private Set<IPath> getResourcePaths(IMavenProjectFacade facade, List<Xpp3Dom> resources) {
	Set<IPath> resourcePaths = new LinkedHashSet<>();
	for(Xpp3Dom resource : resources) {
	IPath folder= null;
	Xpp3Dom xpp3Directory = resource.getChild("directory"); //$NON-NLS-1$
	if (xpp3Directory != null)
	{
	String dir = xpp3Directory.getValue();
	if (StringUtils.isNotEmpty(dir)){
	folder = WTPProjectsUtil.tryProjectRelativePath(facade.getProject(), dir);
	}
	}
	if(folder != null && !folder.isEmpty()) {
	resourcePaths.add(folder);
	}
	}

	return resourcePaths;
	}


	private void executeCopyResources(IMavenProjectFacade facade, ResourceFilteringConfiguration filteringConfiguration, IPath targetFolder, List<Xpp3Dom> resources, IProgressMonitor monitor) throws CoreException {

	//Create a maven request + session
	ResolverConfiguration resolverConfig = facade.getResolverConfiguration();

	List<String> filters = filteringConfiguration.getFilters();
	IMavenProjectRegistry projectManager = MavenPlugin.getMavenProjectRegistry();
	MavenExecutionRequest request = projectManager.createExecutionRequest(facade.getPom(), resolverConfig, monitor);
	request.setRecursive(false);
	request.setOffline(true);

	IMaven maven = MavenPlugin.getMaven();
	MavenProject mavenProject = facade.getMavenProject();

	MavenSession session = maven.createSession(request, mavenProject);
	MavenExecutionPlan executionPlan = maven.calculateExecutionPlan(session, mavenProject, Collections.singletonList("resources:copy-resources"), true, monitor); //$NON-NLS-1$

	MojoExecution copyFilteredResourcesMojo = getExecution(executionPlan, "maven-resources-plugin"); //$NON-NLS-1$

	if (copyFilteredResourcesMojo == null) return;

	Xpp3Dom originalConfig = copyFilteredResourcesMojo.getConfiguration();
	Xpp3Dom configuration = Xpp3DomUtils.mergeXpp3Dom(new Xpp3Dom("configuration"), originalConfig); //$NON-NLS-1$
	boolean parentHierarchyLoaded = false;
	try {
	parentHierarchyLoaded = loadParentHierarchy(facade, monitor);

	//Set resource directories to read
	setupResources(configuration, resources);

	//Force overwrite
	setValue(configuration, "overwrite", Boolean.TRUE); //$NON-NLS-1$

	//Limit placeholder delimiters, otherwise, pages containing @ wouldn't be filtered correctly
	setupDelimiters(configuration);

	//Set output directory to the m2eclipse-wtp webresources directory
	setValue(configuration, "outputDirectory", targetFolder.toPortableString()); //$NON-NLS-1$

	setValue(configuration, "escapeString", filteringConfiguration.getEscapeString()); //$NON-NLS-1$

	setNonfilteredExtensions(configuration, filteringConfiguration.getNonfilteredExtensions());

	//Setup filters
	setupFilters(configuration, filters);

	//Create a maven request + session
	request.setRecursive(false);
	request.setOffline(true);

	//Execute our modified mojo
	copyFilteredResourcesMojo.setConfiguration(configuration);
	copyFilteredResourcesMojo.getMojoDescriptor().setGoal("copy-resources"); //$NON-NLS-1$

	maven.execute(session, copyFilteredResourcesMojo, monitor);

	if (session.getResult().hasExceptions()){

	MavenPluginActivator.getDefault().getMavenMarkerManager().addMarker(facade.getProject(), MavenWtpConstants.WTP_MARKER_FILTERING_ERROR,Messages.ResourceFilteringBuildParticipant_Error_While_Filtering_Resources, -1, IMarker.SEVERITY_ERROR);
	//move exceptions up to the original session, so they can be handled by the maven builder
	//XXX current exceptions refer to maven-resource-plugin (since that's what we used), we should probably
	// throw a new exception instead to indicate the problem(s) come(s) from web resource filtering
	for(Throwable t : session.getResult().getExceptions())
	{
	getSession().getResult().addException(t);
	}
	}

	} finally {
	//Restore original configuration
	copyFilteredResourcesMojo.setConfiguration(originalConfig);
	if (parentHierarchyLoaded) {
	mavenProject.setParent(null);
	}
	}
	}

	/**
	* @param configuration
	* @param extensions
	*/
	private void setNonfilteredExtensions(Xpp3Dom configuration, List<Xpp3Dom> extensions) {
	if (extensions == null \|\| extensions.isEmpty()) {
	return;
	}
	Xpp3Dom nonFilteredFileExtensionsNode = configuration.getChild("nonFilteredFileExtensions"); //$NON-NLS-1$
	if (nonFilteredFileExtensionsNode == null) {
	nonFilteredFileExtensionsNode = new Xpp3Dom("nonFilteredFileExtensions"); //$NON-NLS-1$
	configuration.addChild(nonFilteredFileExtensionsNode);
	} else {
	DomUtils.removeChildren(nonFilteredFileExtensionsNode);
	}

	for (Xpp3Dom ext : extensions) {
	nonFilteredFileExtensionsNode.addChild(ext);
	}
	}

	private void setValue(Xpp3Dom configuration, String childName, Object value) {
	Xpp3Dom childNode = configuration.getChild(childName);
	if (childNode==null){
	childNode = new Xpp3Dom(childName);
	configuration.addChild(childNode);
	}
	childNode.setValue((value == null)?null:value.toString());
	}

	private void setupFilters(Xpp3Dom configuration, List<String> filters) {
	if (!filters.isEmpty()) {
	Xpp3Dom filtersNode = configuration.getChild("filters"); //$NON-NLS-1$

	if (filtersNode==null){
	filtersNode = new Xpp3Dom("filters"); //$NON-NLS-1$
	configuration.addChild(filtersNode);
	} else {
	DomUtils.removeChildren(filtersNode);
	}

	for (String filter : filters) {
	Xpp3Dom filterNode = new Xpp3Dom("filter"); //$NON-NLS-1$
	//Workaround : when run via the BuildParticipant, the maven-resource-plugin won't
	//find a filter defined with a relative path, so we turn it into an absolute one
	IPath filterPath = new Path(filter);
	boolean isAbsolute = false;
	if (filter.startsWith("${basedir}") \|\|filter.startsWith("/") \|\| filterPath.getDevice() != null) { //$NON-NLS-1$ //$NON-NLS-2$
	isAbsolute = true;
	}
	String filterAbsolutePath;
	if (isAbsolute) {
	filterAbsolutePath = filter;
	} else {
	filterAbsolutePath = "${basedir}/"+filter; //$NON-NLS-1$
	}

	filterNode.setValue(filterAbsolutePath);
	filtersNode.addChild(filterNode );
	}
	}
	}

	private void setupDelimiters(Xpp3Dom configuration) {
	Xpp3Dom useDefaultDelimitersNode = configuration.getChild("useDefaultDelimiters"); //$NON-NLS-1$
	if (useDefaultDelimitersNode==null){
	useDefaultDelimitersNode = new Xpp3Dom("useDefaultDelimiters"); //$NON-NLS-1$
	configuration.addChild(useDefaultDelimitersNode);
	}
	useDefaultDelimitersNode.setValue(Boolean.FALSE.toString());

	Xpp3Dom delimitersNode = configuration.getChild("delimiters"); //$NON-NLS-1$
	if (delimitersNode==null){
	delimitersNode = new Xpp3Dom("delimiters"); //$NON-NLS-1$
	configuration.addChild(delimitersNode);
	} else {
	DomUtils.removeChildren(delimitersNode);
	}
	Xpp3Dom delimiter = new Xpp3Dom("delimiter"); //$NON-NLS-1$
	delimiter.setValue("${*}"); //$NON-NLS-1$
	delimitersNode.addChild(delimiter);
	}


	private void setupResources(Xpp3Dom configuration, List<Xpp3Dom> resources) {
	Xpp3Dom resourcesNode = configuration.getChild("resources"); //$NON-NLS-1$
	if (resourcesNode==null){
	resourcesNode = new Xpp3Dom("resources"); //$NON-NLS-1$
	configuration.addChild(resourcesNode);
	} else {
	resourcesNode.setAttribute("default-value", ""); //$NON-NLS-1$ //$NON-NLS-2$
	DomUtils.removeChildren(resourcesNode);
	}
	for (Xpp3Dom resource : resources)
	{
	resourcesNode.addChild(resource);
	}
	}

	private MojoExecution getExecution(MavenExecutionPlan executionPlan, String artifactId) {
	if (executionPlan == null) return null;
	for(MojoExecution execution : executionPlan.getMojoExecutions()) {
	if(artifactId.equals(execution.getArtifactId()) ) {
	return execution;
	}
	}
	return null;
	}

	/**
	* Workaround for https://bugs.eclipse.org/bugs/show_bug.cgi?id=356725.
	* Loads the parent project hierarchy if needed.
	* @param facade
	* @param monitor
	* @return true if parent projects had to be loaded.
	* @throws CoreException
	*/
	private boolean loadParentHierarchy(IMavenProjectFacade facade, IProgressMonitor monitor) throws CoreException {
	boolean loadedParent = false;
	MavenProject mavenProject = facade.getMavenProject();
	try {
	if (mavenProject.getModel().getParent() == null \|\| mavenProject.getParent() != null) {
	//If the method is called without error, we can assume the project has been fully loaded
	//No need to continue.
	return false;
	}
	} catch (IllegalStateException e) {
	//The parent can not be loaded properly
	}
	MavenExecutionRequest request = null;
	while(mavenProject !=null && mavenProject.getModel().getParent() != null) {
	if(monitor.isCanceled()) {
	break;
	}
	if (request == null) {
	request = MavenPlugin.getMavenProjectRegistry().createExecutionRequest(facade, monitor);
	}
	MavenProject parentProject = MavenPlugin.getMaven().resolveParentProject(request, mavenProject, monitor);
	if (parentProject != null) {
	mavenProject.setParent(parentProject);
	loadedParent = true;
	}
	mavenProject = parentProject;
	}
	return loadedParent;
	}


	private static class CleanBuildContext implements BuildContext {

	private BuildContext originalContext;

	CleanBuildContext(BuildContext originalContext) {
	this.originalContext = originalContext;
	}

	public boolean hasDelta(String relpath) {
	return true;
	}

	public boolean hasDelta(File file) {
	return true;
	}

	public boolean hasDelta(List relpaths) {
	return true;
	}

	public void refresh(File file) {
	originalContext.refresh(file);
	}

	public OutputStream newFileOutputStream(File file) throws IOException {
	return originalContext.newFileOutputStream(file);
	}

	public Scanner newScanner(File basedir) {
	return originalContext.newScanner(basedir);
	}

	public Scanner newDeleteScanner(File basedir) {
	return originalContext.newDeleteScanner(basedir);
	}

	public Scanner newScanner(File basedir, boolean ignoreDelta) {
	return originalContext.newScanner(basedir, ignoreDelta);
	}

	public boolean isIncremental() {
	return false;
	}

	public void setValue(String key, Object value) {
	originalContext.setValue(key, value);
	}

	public Object getValue(String key) {
	return originalContext.getValue(key);
	}

	public void addWarning(File file, int line, int column, String message,
	Throwable cause) {
	originalContext.addWarning(file, line, column, message, cause);
	}

	public void addError(File file, int line, int column, String message,
	Throwable cause) {
	originalContext.addError(file, line, column, message, cause);
	}

	public void addMessage(File file, int line, int column, String message,
	int severity, Throwable cause) {
	originalContext.addMessage(file, line, column, message, severity, cause);
	}

	public void removeMessages(File file) {
	originalContext.removeMessages(file);
	}

	public boolean isUptodate(File target, File source) {
	return false;
	}

	}
	}