examples/org.eclipse.team.examples.filesystem/src/org/eclipse/team/examples/pessimistic/PessimisticModificationValidator.java - platform/eclipse.platform.team - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 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 API and implementation
  *******************************************************************************/
 package org.eclipse.team.examples.pessimistic;

 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.Map;
 import java.util.Set;

 import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IFileModificationValidator;
 import org.eclipse.core.resources.ResourcesPlugin;
 import org.eclipse.core.resources.team.FileModificationValidationContext;
 import org.eclipse.core.resources.team.FileModificationValidator;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.MultiStatus;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.jface.preference.IPreferenceStore;
 import org.eclipse.jface.viewers.ILabelProvider;
 import org.eclipse.jface.viewers.ITreeContentProvider;
 import org.eclipse.jface.window.Window;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.Display;
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.swt.widgets.Widget;
 import org.eclipse.ui.dialogs.CheckedTreeSelectionDialog;
 import org.eclipse.ui.model.WorkbenchLabelProvider;
 import org.eclipse.ui.views.navigator.ResourceComparator;

 /**
  * The <code>PessimisticModificationValidator</code> is an
  * implementation of the <code>IFileModificationValidator</code> for the
  * <code>PessimisticFilesystemProvider</code>.
  *
  * @see PessimiticFilesystemProvider
  * @see IFileModificationValidator
  */
 public class PessimisticModificationValidator
 	extends FileModificationValidator {
 	/*
 	 * The provider for this validator
 	 */
 	private PessimisticFilesystemProvider fProvider;

 	public PessimisticModificationValidator(PessimisticFilesystemProvider provider) {
 		fProvider= provider;
 	}

 	/**
 	 * @see IFileModificationValidator#validateEdit(IFile[], Object)
 	 */
  	public IStatus validateEdit(IFile[] files, FileModificationValidationContext context) {
     	if (files.length == 0) {
 	        return new Status( IStatus.OK, getUid(), IStatus.OK, "OK", null);
 	    }

 	    Set checkOut = new HashSet();
 		int reloadCount = 0;
 	  	int checkoutFailCount = 0;

 		Map validateEditStatusMap= new HashMap(files.length);

 	    for ( int i = 0 ; i < files.length; i++ ) {
 	        IFile file= files[i];

 	        if (fProvider.isControlled(file) ) {
 	        	if (fProvider.isCheckedout(file)) {
 		            setValidateEditStatus(validateEditStatusMap, file,
 		               IPessimisticFilesystemConstants.STATUS_OK_TO_EDIT );
 	        	} else {
 	        		checkOut.add(file);
 	        	}
 	        } else {
 				setValidateEditStatus(validateEditStatusMap, file,
 					IPessimisticFilesystemConstants.STATUS_OK_TO_EDIT);
 	        }
 	    }

 	    if (!checkOut.isEmpty()) {
 	     	if (context != null) {
 	     		boolean shouldFail= shouldFailValidateEdit();
 	            int statusCode = checkout(checkOut, IPessimisticFilesystemConstants.PREF_CHECKED_IN_FILES_EDITED, shouldFail, context);
 	            if (shouldFail) {
 					return new Status( IStatus.ERROR, getUid(), IStatus.ERROR, "Fail Validate Edit Preference true", null);
 				}
 	            if(statusCode == IStatus.CANCEL) {
 	            	return new Status( IStatus.CANCEL, getUid(), IStatus.ERROR, "Checkout canceled by user", null);
 	            }
             } else {
             	if (isAutomaticCheckout()) {
 		            if (shouldFailValidateEdit()) {
 						return new Status( IStatus.ERROR, getUid(), IStatus.ERROR, "Fail Validate Edit Preference true", null);
 					}

 					checkout(checkOut);
             	}
             }

 	        for (Iterator i= checkOut.iterator(); i.hasNext(); ) {
 				IFile file = (IFile) i.next();

 				if ( fProvider.isCheckedout(file) ) {
 			    	if ( !fProvider.hasContentChanged(file) ) {
 						setValidateEditStatus(validateEditStatusMap, file,
 				    		IPessimisticFilesystemConstants.STATUS_OK_TO_EDIT );
 			    	} else {
 	                    reloadCount++;
 						setValidateEditStatus(validateEditStatusMap, file,
 	                        IPessimisticFilesystemConstants.STATUS_PROMPT_FOR_RELOAD );
 			    	}
 				} else {
 	                checkoutFailCount++;
 				}
 		    }
 	    }

 	    if (reloadCount + checkoutFailCount == 0) {
 	        return new Status( IStatus.OK, getUid(), IStatus.OK, "OK", null);
 	    }

 	    if (checkoutFailCount == files.length) {
 	        return new Status( IStatus.ERROR, getUid(), IStatus.ERROR, "No files were checked out.", null);
 	    }

 	    IStatus children[] = new Status[ files.length ];

 	    int mask = IPessimisticFilesystemConstants.STATUS_OK_TO_EDIT |
 	               	IPessimisticFilesystemConstants.STATUS_PROMPT_FOR_RELOAD;

 	    for (int i = 0; i < files.length; i++) {
 	    	int result = getValidateEditStatus(validateEditStatusMap, files[i]);
 	 		if ((result & mask) != 0) {
 		    	children[i] = new Status( IStatus.OK, getUid(), IStatus.OK, "OK", null);
 	        } else {
 	            children[i] = new Status( IStatus.ERROR, getUid(), IStatus.ERROR, "File " + files[i].getName() + " could not be checked out.", null);
 	        }
 	    }
 	    return new MultiStatus( getUid(), IStatus.OK, children, "Some files were not successfully checked out", null);
 	}

 	/**
 	 * @see IFileModificationValidator#validateSave(IFile)
 	 */
 	public IStatus validateSave(IFile file) {
 		int checkedInFilesSaved = getPreferences().getInt(IPessimisticFilesystemConstants.PREF_CHECKED_IN_FILES_SAVED);
 		if (checkedInFilesSaved == IPessimisticFilesystemConstants.OPTION_DO_NOTHING) {
 			return new Status( IStatus.OK, getUid(), IStatus.OK, "", null);
 		}


 		IStatus status = new Status( IStatus.OK, getUid(), IStatus.OK,
 			                      	"File is writable", null);

 		if (!fProvider.isControlled(file)) {
 			return status;
 		}

 		if (fProvider.isIgnored(file)) {
 			return status;
 		}

 		if (fProvider.isCheckedout(file)) {
 			return status;
 		}
 		Set files= new HashSet(1);
 		files.add(file);

 		checkout(files, IPessimisticFilesystemConstants.PREF_CHECKED_IN_FILES_SAVED, false, null);

 		if (fProvider.isCheckedout(file)) {
 			return status;
 		}
 		return new Status(
 			IStatus.ERROR,
 			getUid(),
 			IStatus.ERROR,
 			file.getProjectRelativePath() + " could not be checked out",
 			null);
 	}

 	/*
 	 * Convenience method to get the plugin id
 	 */
 	private String getUid() {
 		return PessimisticFilesystemProviderPlugin.PLUGIN_ID;
 	}

 	/*
 	 * Convenience method to answer if the fail validate edit preference
 	 * has been set.
 	 */
 	private boolean shouldFailValidateEdit() {
 		return getPreferences().getBoolean(IPessimisticFilesystemConstants.PREF_FAIL_VALIDATE_EDIT);
 	}

 	/*
 	 * Convenience method to answer if the check out preference is set to automatic.
 	 */
 	private boolean isAutomaticCheckout() {
 		return getPreferences().getInt(IPessimisticFilesystemConstants.PREF_CHECKED_IN_FILES_EDITED_NOPROMPT) == IPessimisticFilesystemConstants.OPTION_AUTOMATIC;
 	}

 	/*
 	 * Optionally prompts the user to select which resources should be
 	 * checked out, and then checks the selected resources.
 	 */
 	private int promptAndCheckout(Set resources, boolean beQuiet, boolean shouldFail, Object context) {
 		if (resources.isEmpty()) {
 			return IStatus.OK;
 		}

 		Set temp= new HashSet(resources.size());
 		for(Iterator i= resources.iterator(); i.hasNext(); ) {
 			IFile resource= (IFile)i.next();
 			if (fProvider.isControlled(resource) && !fProvider.isCheckedout(resource))
 				temp.add(resource);
 		}
 		resources= temp;
 		final int[] statusCode = new int[] {IStatus.OK};
 		if (!beQuiet && !resources.isEmpty()) {
 			final Shell shell= getShell(context);
 			if (shell != null && !shell.isDisposed()) {
 				Display display = shell.getDisplay();
 				final Set[] result = {resources};
 				display.syncExec(new Runnable() {
 					public void run() {
 						ILabelProvider labelProvider= new WorkbenchLabelProvider();
 						Object[] resourceArray= result[0].toArray();
 						ITreeContentProvider contentProvider= new ResourceSetContentProvider(result[0]);
 						CheckedTreeSelectionDialog dialog= new CheckedTreeSelectionDialog(shell, labelProvider, contentProvider);
 						dialog.setMessage("Select resources to be checked out.");
 						dialog.setTitle("Check out resources");
 						dialog.setContainerMode(true);
 						dialog.setBlockOnOpen(true);
 						dialog.setComparator(new ResourceComparator(ResourceComparator.NAME));
 						dialog.setExpandedElements(resourceArray);
 						dialog.setInitialSelections(resourceArray);
 						dialog.setInput(ResourcesPlugin.getWorkspace().getRoot());
 						int status= dialog.open();
 						result[0]= null;
 						if (status == Window.OK) {
 							Object[] results= dialog.getResult();
 							result[0] = new HashSet(results.length);
 							for (int i= 0; i < results.length; i++) {
 								result[0].add(results[i]);
 							}
 						} else if(status == Window.CANCEL) {
 							statusCode[0] = IStatus.CANCEL;
 						}
 					}
 				});
 				resources= result[0];
 			} else {
 				resources= null;
 				PessimisticFilesystemProviderPlugin.getInstance().logError(new RuntimeException(), "Context is invalid: " + context);
 			}
 		}

 		if (resources != null && !resources.isEmpty() && !shouldFail) {
 			checkout(resources);
 		}
 		return statusCode[0];
 	}

 	/*
 	 * Checks out the files contained in the resources set
 	 */
 	private void checkout(Set resources) {
 		if (resources.isEmpty())
 			return;
 		IFile[] checkOut= new IFile[resources.size()];
 		resources.toArray(checkOut);
 		fProvider.checkout(checkOut, null);
 	}

 	/*
 	 * Convenience method to get the plugin preferences.
 	 */
 	private IPreferenceStore getPreferences() {
 		return PessimisticFilesystemProviderPlugin.getInstance().getPreferenceStore();
 	}

 	/*
 	 * Checks out the files if necessary and if the preferences allow.
 	 */
 	private int checkout(Set resources, String itemId, boolean shouldFail, Object context) {
 		if (resources.isEmpty()) {
 			return IStatus.OK;
 		}

 		int preference= getPreferences().getInt(itemId);

 		if (preference == IPessimisticFilesystemConstants.OPTION_DO_NOTHING)
 			return IStatus.OK;

 		boolean beQuiet= false;
 		if (preference == IPessimisticFilesystemConstants.OPTION_AUTOMATIC) {
 			beQuiet= true;
 		}
 		return promptAndCheckout(resources, beQuiet, shouldFail, context);
 	}

 	/*
 	 * Convenience method to set the validate edit status for the given resource.
 	 */
 	private static void setValidateEditStatus(Map map, IFile resource, int status) {
 		map.put(resource, Integer.valueOf(status));
 	}

 	/*
 	 * Convenience method to get the validate edit status for the given resource.
 	 */
 	private static int getValidateEditStatus(Map map, IFile resource) {
 		Integer i= (Integer)map.get(resource);
 		if (i == null)
 			return 0;
 		return i.intValue();
 	}

 	/*
 	 * Convenience method to get a shell from an object.
 	 */
 	private Shell getShell(Object context) {
 		if (context instanceof FileModificationValidationContext) {
 			FileModificationValidationContext fmvc = (FileModificationValidationContext) context;
 			return (Shell)fmvc.getShell();
 		}

 		if (context instanceof Shell) {
 			return (Shell)context;
 		}

 		if (context instanceof Control) {
 			Control control= (Control)context;
 			return control.getShell();
 		}

 		if (context instanceof Widget) {
 			Widget widget= (Widget)context;
 			return widget.getDisplay().getActiveShell();
 		}

 		return null;
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 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 API and implementation
	*******************************************************************************/
	package org.eclipse.team.examples.pessimistic;

	import java.util.HashMap;
	import java.util.HashSet;
	import java.util.Iterator;
	import java.util.Map;
	import java.util.Set;

	import org.eclipse.core.resources.IFile;
	import org.eclipse.core.resources.IFileModificationValidator;
	import org.eclipse.core.resources.ResourcesPlugin;
	import org.eclipse.core.resources.team.FileModificationValidationContext;
	import org.eclipse.core.resources.team.FileModificationValidator;
	import org.eclipse.core.runtime.IStatus;
	import org.eclipse.core.runtime.MultiStatus;
	import org.eclipse.core.runtime.Status;
	import org.eclipse.jface.preference.IPreferenceStore;
	import org.eclipse.jface.viewers.ILabelProvider;
	import org.eclipse.jface.viewers.ITreeContentProvider;
	import org.eclipse.jface.window.Window;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.swt.widgets.Display;
	import org.eclipse.swt.widgets.Shell;
	import org.eclipse.swt.widgets.Widget;
	import org.eclipse.ui.dialogs.CheckedTreeSelectionDialog;
	import org.eclipse.ui.model.WorkbenchLabelProvider;
	import org.eclipse.ui.views.navigator.ResourceComparator;

	/**
	* The <code>PessimisticModificationValidator</code> is an
	* implementation of the <code>IFileModificationValidator</code> for the
	* <code>PessimisticFilesystemProvider</code>.
	*
	* @see PessimiticFilesystemProvider
	* @see IFileModificationValidator
	*/
	public class PessimisticModificationValidator
	extends FileModificationValidator {
	/*
	* The provider for this validator
	*/
	private PessimisticFilesystemProvider fProvider;

	public PessimisticModificationValidator(PessimisticFilesystemProvider provider) {
	fProvider= provider;
	}

	/**
	* @see IFileModificationValidator#validateEdit(IFile[], Object)
	*/
	public IStatus validateEdit(IFile[] files, FileModificationValidationContext context) {
	if (files.length == 0) {
	return new Status( IStatus.OK, getUid(), IStatus.OK, "OK", null);
	}

	Set checkOut = new HashSet();
	int reloadCount = 0;
	int checkoutFailCount = 0;

	Map validateEditStatusMap= new HashMap(files.length);

	for ( int i = 0 ; i < files.length; i++ ) {
	IFile file= files[i];

	if (fProvider.isControlled(file) ) {
	if (fProvider.isCheckedout(file)) {
	setValidateEditStatus(validateEditStatusMap, file,
	IPessimisticFilesystemConstants.STATUS_OK_TO_EDIT );
	} else {
	checkOut.add(file);
	}
	} else {
	setValidateEditStatus(validateEditStatusMap, file,
	IPessimisticFilesystemConstants.STATUS_OK_TO_EDIT);
	}
	}

	if (!checkOut.isEmpty()) {
	if (context != null) {
	boolean shouldFail= shouldFailValidateEdit();
	int statusCode = checkout(checkOut, IPessimisticFilesystemConstants.PREF_CHECKED_IN_FILES_EDITED, shouldFail, context);
	if (shouldFail) {
	return new Status( IStatus.ERROR, getUid(), IStatus.ERROR, "Fail Validate Edit Preference true", null);
	}
	if(statusCode == IStatus.CANCEL) {
	return new Status( IStatus.CANCEL, getUid(), IStatus.ERROR, "Checkout canceled by user", null);
	}
	} else {
	if (isAutomaticCheckout()) {
	if (shouldFailValidateEdit()) {
	return new Status( IStatus.ERROR, getUid(), IStatus.ERROR, "Fail Validate Edit Preference true", null);
	}

	checkout(checkOut);
	}
	}

	for (Iterator i= checkOut.iterator(); i.hasNext(); ) {
	IFile file = (IFile) i.next();

	if ( fProvider.isCheckedout(file) ) {
	if ( !fProvider.hasContentChanged(file) ) {
	setValidateEditStatus(validateEditStatusMap, file,
	IPessimisticFilesystemConstants.STATUS_OK_TO_EDIT );
	} else {
	reloadCount++;
	setValidateEditStatus(validateEditStatusMap, file,
	IPessimisticFilesystemConstants.STATUS_PROMPT_FOR_RELOAD );
	}
	} else {
	checkoutFailCount++;
	}
	}
	}

	if (reloadCount + checkoutFailCount == 0) {
	return new Status( IStatus.OK, getUid(), IStatus.OK, "OK", null);
	}

	if (checkoutFailCount == files.length) {
	return new Status( IStatus.ERROR, getUid(), IStatus.ERROR, "No files were checked out.", null);
	}

	IStatus children[] = new Status[ files.length ];

	int mask = IPessimisticFilesystemConstants.STATUS_OK_TO_EDIT \|
	IPessimisticFilesystemConstants.STATUS_PROMPT_FOR_RELOAD;

	for (int i = 0; i < files.length; i++) {
	int result = getValidateEditStatus(validateEditStatusMap, files[i]);
	if ((result & mask) != 0) {
	children[i] = new Status( IStatus.OK, getUid(), IStatus.OK, "OK", null);
	} else {
	children[i] = new Status( IStatus.ERROR, getUid(), IStatus.ERROR, "File " + files[i].getName() + " could not be checked out.", null);
	}
	}
	return new MultiStatus( getUid(), IStatus.OK, children, "Some files were not successfully checked out", null);
	}

	/**
	* @see IFileModificationValidator#validateSave(IFile)
	*/
	public IStatus validateSave(IFile file) {
	int checkedInFilesSaved = getPreferences().getInt(IPessimisticFilesystemConstants.PREF_CHECKED_IN_FILES_SAVED);
	if (checkedInFilesSaved == IPessimisticFilesystemConstants.OPTION_DO_NOTHING) {
	return new Status( IStatus.OK, getUid(), IStatus.OK, "", null);
	}


	IStatus status = new Status( IStatus.OK, getUid(), IStatus.OK,
	"File is writable", null);

	if (!fProvider.isControlled(file)) {
	return status;
	}

	if (fProvider.isIgnored(file)) {
	return status;
	}

	if (fProvider.isCheckedout(file)) {
	return status;
	}
	Set files= new HashSet(1);
	files.add(file);

	checkout(files, IPessimisticFilesystemConstants.PREF_CHECKED_IN_FILES_SAVED, false, null);

	if (fProvider.isCheckedout(file)) {
	return status;
	}
	return new Status(
	IStatus.ERROR,
	getUid(),
	IStatus.ERROR,
	file.getProjectRelativePath() + " could not be checked out",
	null);
	}

	/*
	* Convenience method to get the plugin id
	*/
	private String getUid() {
	return PessimisticFilesystemProviderPlugin.PLUGIN_ID;
	}

	/*
	* Convenience method to answer if the fail validate edit preference
	* has been set.
	*/
	private boolean shouldFailValidateEdit() {
	return getPreferences().getBoolean(IPessimisticFilesystemConstants.PREF_FAIL_VALIDATE_EDIT);
	}

	/*
	* Convenience method to answer if the check out preference is set to automatic.
	*/
	private boolean isAutomaticCheckout() {
	return getPreferences().getInt(IPessimisticFilesystemConstants.PREF_CHECKED_IN_FILES_EDITED_NOPROMPT) == IPessimisticFilesystemConstants.OPTION_AUTOMATIC;
	}

	/*
	* Optionally prompts the user to select which resources should be
	* checked out, and then checks the selected resources.
	*/
	private int promptAndCheckout(Set resources, boolean beQuiet, boolean shouldFail, Object context) {
	if (resources.isEmpty()) {
	return IStatus.OK;
	}

	Set temp= new HashSet(resources.size());
	for(Iterator i= resources.iterator(); i.hasNext(); ) {
	IFile resource= (IFile)i.next();
	if (fProvider.isControlled(resource) && !fProvider.isCheckedout(resource))
	temp.add(resource);
	}
	resources= temp;
	final int[] statusCode = new int[] {IStatus.OK};
	if (!beQuiet && !resources.isEmpty()) {
	final Shell shell= getShell(context);
	if (shell != null && !shell.isDisposed()) {
	Display display = shell.getDisplay();
	final Set[] result = {resources};
	display.syncExec(new Runnable() {
	public void run() {
	ILabelProvider labelProvider= new WorkbenchLabelProvider();
	Object[] resourceArray= result[0].toArray();
	ITreeContentProvider contentProvider= new ResourceSetContentProvider(result[0]);
	CheckedTreeSelectionDialog dialog= new CheckedTreeSelectionDialog(shell, labelProvider, contentProvider);
	dialog.setMessage("Select resources to be checked out.");
	dialog.setTitle("Check out resources");
	dialog.setContainerMode(true);
	dialog.setBlockOnOpen(true);
	dialog.setComparator(new ResourceComparator(ResourceComparator.NAME));
	dialog.setExpandedElements(resourceArray);
	dialog.setInitialSelections(resourceArray);
	dialog.setInput(ResourcesPlugin.getWorkspace().getRoot());
	int status= dialog.open();
	result[0]= null;
	if (status == Window.OK) {
	Object[] results= dialog.getResult();
	result[0] = new HashSet(results.length);
	for (int i= 0; i < results.length; i++) {
	result[0].add(results[i]);
	}
	} else if(status == Window.CANCEL) {
	statusCode[0] = IStatus.CANCEL;
	}
	}
	});
	resources= result[0];
	} else {
	resources= null;
	PessimisticFilesystemProviderPlugin.getInstance().logError(new RuntimeException(), "Context is invalid: " + context);
	}
	}

	if (resources != null && !resources.isEmpty() && !shouldFail) {
	checkout(resources);
	}
	return statusCode[0];
	}

	/*
	* Checks out the files contained in the resources set
	*/
	private void checkout(Set resources) {
	if (resources.isEmpty())
	return;
	IFile[] checkOut= new IFile[resources.size()];
	resources.toArray(checkOut);
	fProvider.checkout(checkOut, null);
	}

	/*
	* Convenience method to get the plugin preferences.
	*/
	private IPreferenceStore getPreferences() {
	return PessimisticFilesystemProviderPlugin.getInstance().getPreferenceStore();
	}

	/*
	* Checks out the files if necessary and if the preferences allow.
	*/
	private int checkout(Set resources, String itemId, boolean shouldFail, Object context) {
	if (resources.isEmpty()) {
	return IStatus.OK;
	}

	int preference= getPreferences().getInt(itemId);

	if (preference == IPessimisticFilesystemConstants.OPTION_DO_NOTHING)
	return IStatus.OK;

	boolean beQuiet= false;
	if (preference == IPessimisticFilesystemConstants.OPTION_AUTOMATIC) {
	beQuiet= true;
	}
	return promptAndCheckout(resources, beQuiet, shouldFail, context);
	}

	/*
	* Convenience method to set the validate edit status for the given resource.
	*/
	private static void setValidateEditStatus(Map map, IFile resource, int status) {
	map.put(resource, Integer.valueOf(status));
	}

	/*
	* Convenience method to get the validate edit status for the given resource.
	*/
	private static int getValidateEditStatus(Map map, IFile resource) {
	Integer i= (Integer)map.get(resource);
	if (i == null)
	return 0;
	return i.intValue();
	}

	/*
	* Convenience method to get a shell from an object.
	*/
	private Shell getShell(Object context) {
	if (context instanceof FileModificationValidationContext) {
	FileModificationValidationContext fmvc = (FileModificationValidationContext) context;
	return (Shell)fmvc.getShell();
	}

	if (context instanceof Shell) {
	return (Shell)context;
	}

	if (context instanceof Control) {
	Control control= (Control)context;
	return control.getShell();
	}

	if (context instanceof Widget) {
	Widget widget= (Widget)context;
	return widget.getDisplay().getActiveShell();
	}

	return null;
	}
	}