target_explorer/plugins/org.eclipse.tcf.te.tcf.filesystem.ui/src/org/eclipse/tcf/te/tcf/filesystem/ui/dialogs/FSFolderSelectionDialog.java - tcf/org.eclipse.tcf - Git at Google

 /*******************************************************************************
  * Copyright (c) 2011, 2015 Wind River Systems, Inc. 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:
  * Wind River Systems - initial API and implementation
  *******************************************************************************/
 package org.eclipse.tcf.te.tcf.filesystem.ui.dialogs;

 import java.util.Iterator;
 import java.util.List;

 import org.eclipse.core.runtime.Assert;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.jface.action.Action;
 import org.eclipse.jface.action.IAction;
 import org.eclipse.jface.action.IMenuListener;
 import org.eclipse.jface.action.IMenuManager;
 import org.eclipse.jface.action.MenuManager;
 import org.eclipse.jface.viewers.DecoratingLabelProvider;
 import org.eclipse.jface.viewers.ILabelDecorator;
 import org.eclipse.jface.viewers.ILabelProvider;
 import org.eclipse.jface.viewers.ISelection;
 import org.eclipse.jface.viewers.IStructuredSelection;
 import org.eclipse.jface.viewers.ITreeContentProvider;
 import org.eclipse.jface.viewers.TreeViewer;
 import org.eclipse.jface.viewers.Viewer;
 import org.eclipse.jface.viewers.ViewerFilter;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.KeyAdapter;
 import org.eclipse.swt.events.KeyEvent;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.widgets.Button;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Menu;
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.tcf.te.tcf.filesystem.core.interfaces.runtime.IFSTreeNode;
 import org.eclipse.tcf.te.tcf.filesystem.core.interfaces.runtime.IRuntimeModel;
 import org.eclipse.tcf.te.tcf.filesystem.core.model.ModelManager;
 import org.eclipse.tcf.te.tcf.filesystem.ui.activator.UIPlugin;
 import org.eclipse.tcf.te.tcf.filesystem.ui.controls.FSTreeContentProvider;
 import org.eclipse.tcf.te.tcf.filesystem.ui.controls.FSTreeViewerSorter;
 import org.eclipse.tcf.te.tcf.filesystem.ui.interfaces.IFSConstants;
 import org.eclipse.tcf.te.tcf.filesystem.ui.internal.ImageConsts;
 import org.eclipse.tcf.te.tcf.filesystem.ui.internal.columns.FSTreeElementLabelProvider;
 import org.eclipse.tcf.te.tcf.filesystem.ui.internal.handlers.MoveFilesHandler;
 import org.eclipse.tcf.te.tcf.filesystem.ui.nls.Messages;
 import org.eclipse.tcf.te.tcf.locator.interfaces.nodes.IPeerNode;
 import org.eclipse.tcf.te.ui.trees.FilterDescriptor;
 import org.eclipse.tcf.te.ui.trees.ViewerStateManager;
 import org.eclipse.ui.IDecoratorManager;
 import org.eclipse.ui.IWorkbench;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.dialogs.ElementTreeSelectionDialog;
 import org.eclipse.ui.dialogs.ISelectionStatusValidator;

 /**
  * <p>
  * The folder selection dialog for a remote file system. To populate the tree of the selection
  * dialog with the file system, you should call <code>
  * ElementTreeSelectionDialog.setInput</code> to specify the peer model of the remote target. In
  * order to validate the destination folder, you should also specify the nodes to be moved. The file
  * selection dialog is of single selection. You can get the selected result by calling
  * <code>getFirstResult</code>. The type of selected folder is an instance of IFSTreeNode.
  * </p>
  * <p>
  * The following is a snippet of example code:
  *
  * <pre>
  * FSFolderSelectionDialog dialog = new FSFolderSelectionDialog(shell);
  * dialog.setInput(peer);
  * dialog.setMovedNodes(nodes);
  * if (dialog.open() == Window.OK) {
  * 	Object obj = dialog.getFirstResult();
  * 	Assert.isTrue(obj instanceof IFSTreeNode);
  * 	IFSTreeNode folder = (IFSTreeNode) obj;
  * 	// Use folder ...
  * }
  * </pre>
  *
  * @see MoveFilesHandler
  */
 public final class FSFolderSelectionDialog extends ElementTreeSelectionDialog {
 	// The nodes that are being moved.
 	private List<IFSTreeNode> movedNodes;
 	private final int mode;

 	public static final int MODE_ALL = 0;
 	public static final int MODE_ALL_WARNING_NOT_WRITABLE = 1;
 	public static final int MODE_ONLY_WRITABLE = 2;

 	/**
 	 * Create an FSFolderSelectionDialog using the specified shell as the parent.
 	 *
 	 * @param parentShell The parent shell.
 	 */
 	public FSFolderSelectionDialog(Shell parentShell) {
 		this(parentShell, MODE_ONLY_WRITABLE);
 	}

 	/**
 	 * Create an FSFolderSelectionDialog using the specified shell as the parent.
 	 *
 	 * @param parentShell The parent shell.
 	 * @param mode The mode of this dialog.
 	 */
 	public FSFolderSelectionDialog(Shell parentShell, int mode) {
 		this(parentShell, new FSTreeElementLabelProvider(), new FSTreeContentProvider(), mode);
 	}

 	/**
 	 * Create an FSFolderSelectionDialog using the specified shell, an FSTreeLabelProvider, and a
 	 * content provider that provides the tree nodes.
 	 *
 	 * @param parentShell The parent shell.
 	 * @param labelProvider The label provider.
 	 * @param contentProvider The content provider.
 	 * @param mode The mode of this dialog.
 	 */
 	private FSFolderSelectionDialog(Shell parentShell, ILabelProvider labelProvider, ITreeContentProvider contentProvider, int mode) {
 		super(parentShell, createDecoratingLabelProvider(labelProvider), contentProvider);
 		this.mode = mode;
 		setTitle(Messages.FSFolderSelectionDialog_MoveDialogTitle);
 		setMessage(Messages.FSFolderSelectionDialog_MoveDialogMessage);
 		this.setAllowMultiple(false);
 		this.setComparator(new FSTreeViewerSorter());
 		this.addFilter(new DirectoryFilter());
 		this.setStatusLineAboveButtons(true);
 		this.setValidator(new ISelectionStatusValidator() {
 			@Override
 			public IStatus validate(final Object[] selection) {
 				return isValidFolder(selection);
 			}
 		});
 	}

 	/**
 	 * The viewer filter used to filter out files.
 	 */
 	static class DirectoryFilter extends ViewerFilter {
 		@Override
 		public boolean select(Viewer viewer, Object parentElement, Object element) {
 			if (element instanceof IFSTreeNode) {
 				IFSTreeNode node = (IFSTreeNode) element;
 				if(node.isFile()) return false;
 			}
 			return true;
 		}
 	}

 	/*
 	 * (non-Javadoc)
 	 * @see org.eclipse.ui.dialogs.ElementTreeSelectionDialog#setInput(java.lang.Object)
 	 */
 	@Override
 	public void setInput(Object input) {
 		super.setInput(input);
 		FilterDescriptor[] filterDescriptors = ViewerStateManager.getInstance().getFilterDescriptors(IFSConstants.ID_TREE_VIEWER_FS, input);
 		Assert.isNotNull(filterDescriptors);
 		for (FilterDescriptor descriptor : filterDescriptors) {
 			if (descriptor.isEnabled()) {
 				addFilter(descriptor.getFilter());
 			}
 		}
 	}

 	/**
 	 * Create a decorating label provider using the specified label provider.
 	 *
 	 * @param labelProvider The label provider that actually provides labels and images.
 	 * @return The decorating label provider.
 	 */
 	private static ILabelProvider createDecoratingLabelProvider(ILabelProvider labelProvider) {
 		IWorkbench workbench = PlatformUI.getWorkbench();
 		IDecoratorManager manager = workbench.getDecoratorManager();
 		ILabelDecorator decorator = manager.getLabelDecorator();
 		return new DecoratingLabelProvider(labelProvider,decorator);
 	}

 	/**
 	 * Set the nodes that are about to be moved.
 	 *
 	 * @param movedNodes The nodes.
 	 */
 	public void setMovedNodes(List<IFSTreeNode> movedNodes) {
 		this.movedNodes = movedNodes;
 	}

 	@Override
     public TreeViewer getTreeViewer() {
 		return super.getTreeViewer();
 	}

 	/**
 	 * Create the tree viewer and set it to the label provider.
 	 */
 	@Override
 	protected TreeViewer doCreateTreeViewer(Composite parent, int style) {
 		TreeViewer viewer = super.doCreateTreeViewer(parent, style);

 		Button refreshAll = new Button(parent, SWT.PUSH);
 		refreshAll.setText(Messages.FSFolderSelectionDialog_RefreshAll_menu);
 		refreshAll.addSelectionListener(new SelectionAdapter() {
 			@Override
 			public void widgetSelected(SelectionEvent e) {
 				refreshModel();
 			}
 		});

 		viewer.getTree().addKeyListener(new KeyAdapter() {
 			/* (non-Javadoc)
 			 * @see org.eclipse.swt.events.KeyAdapter#keyReleased(org.eclipse.swt.events.KeyEvent)
 			 */
 			@Override
 			public void keyReleased(KeyEvent e) {
 				if (e.keyCode == SWT.F5) {
 					refresh();
 				}
 			}
 		});
 		viewer.getTree().setLinesVisible(false);

 		MenuManager menuMgr = new MenuManager();
 	    menuMgr.setRemoveAllWhenShown(true);
 	    menuMgr.addMenuListener(new IMenuListener() {
 	        @Override
             public void menuAboutToShow(IMenuManager manager) {
 	        	IAction action = new Action(Messages.FSFolderSelectionDialog_Refresh_menu, UIPlugin.getImageDescriptor(ImageConsts.REFRESH_IMAGE)) {
 	            	@Override
 	            	public void run() {
 	            	    refresh();
 	            	}
 	            };
 	            action.setAccelerator(SWT.F5);
 	            manager.add(action);
 	        }
 	    });
 	    Menu menu = menuMgr.createContextMenu(viewer.getControl());
 	    viewer.getControl().setMenu(menu);

 	    return viewer;
 	}

 	public void refresh() {
 		ISelection sel = getTreeViewer().getSelection();
 		if (sel instanceof IStructuredSelection && !sel.isEmpty()) {
 			Iterator<Object> it = ((IStructuredSelection)sel).iterator();
 			while (it.hasNext()) {
 				Object node = it.next();
 				if (node instanceof IFSTreeNode) {
 					refreshNode((IFSTreeNode)node);
 				}
 				else {
 					refreshModel();
 					return;
 				}
 			}
 		}
 		else {
 			refreshModel();
 		}
 	}

 	protected void refreshNode(final IFSTreeNode treeNode) {
 		treeNode.operationRefresh(true).runInJob(null);
 	}

 	protected void refreshModel() {
 		Object input = getTreeViewer().getInput();
 		if (input instanceof IPeerNode) {
 			IRuntimeModel rtm = ModelManager.getRuntimeModel((IPeerNode)input);
 			if (rtm != null)
 				refreshNode(rtm.getRoot());
 		}
 	}


 	private final static IStatus error = new Status(IStatus.ERROR, UIPlugin.getUniqueIdentifier(), null);
 	private final static IStatus errorNotWritable = new Status(IStatus.ERROR, UIPlugin.getUniqueIdentifier(), Messages.FSFolderSelectionDialog_notWritable_error);
 	private final static IStatus warningNotWritable = new Status(IStatus.WARNING, UIPlugin.getUniqueIdentifier(), Messages.FSFolderSelectionDialog_notWritable_warning);

 	/**
 	 * If the specified selection is a valid folder to be selected.
 	 *
 	 * @param selection The selected folders.
 	 * @return An error status if it is invalid or an OK status indicating it is valid.
 	 */
 	IStatus isValidFolder(Object[] selection) {
 		if (selection == null || selection.length == 0) {
 			return error;
 		}
 		if (!(selection[0] instanceof IFSTreeNode)) {
 			return error;
 		}
 		IFSTreeNode target = (IFSTreeNode) selection[0];
 		if (movedNodes != null) {
 			for (IFSTreeNode node : movedNodes) {
 				if (node == target || node.isAncestorOf(target)) {
 					return error;
 				}
 			}
 		}
 		if(mode != MODE_ALL && !target.isWritable()) {
 			return mode == MODE_ONLY_WRITABLE ? errorNotWritable : warningNotWritable;
 		}
 		return Status.OK_STATUS;
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2011, 2015 Wind River Systems, Inc. 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:
	* Wind River Systems - initial API and implementation
	*******************************************************************************/
	package org.eclipse.tcf.te.tcf.filesystem.ui.dialogs;

	import java.util.Iterator;
	import java.util.List;

	import org.eclipse.core.runtime.Assert;
	import org.eclipse.core.runtime.IStatus;
	import org.eclipse.core.runtime.Status;
	import org.eclipse.jface.action.Action;
	import org.eclipse.jface.action.IAction;
	import org.eclipse.jface.action.IMenuListener;
	import org.eclipse.jface.action.IMenuManager;
	import org.eclipse.jface.action.MenuManager;
	import org.eclipse.jface.viewers.DecoratingLabelProvider;
	import org.eclipse.jface.viewers.ILabelDecorator;
	import org.eclipse.jface.viewers.ILabelProvider;
	import org.eclipse.jface.viewers.ISelection;
	import org.eclipse.jface.viewers.IStructuredSelection;
	import org.eclipse.jface.viewers.ITreeContentProvider;
	import org.eclipse.jface.viewers.TreeViewer;
	import org.eclipse.jface.viewers.Viewer;
	import org.eclipse.jface.viewers.ViewerFilter;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.KeyAdapter;
	import org.eclipse.swt.events.KeyEvent;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.widgets.Button;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Menu;
	import org.eclipse.swt.widgets.Shell;
	import org.eclipse.tcf.te.tcf.filesystem.core.interfaces.runtime.IFSTreeNode;
	import org.eclipse.tcf.te.tcf.filesystem.core.interfaces.runtime.IRuntimeModel;
	import org.eclipse.tcf.te.tcf.filesystem.core.model.ModelManager;
	import org.eclipse.tcf.te.tcf.filesystem.ui.activator.UIPlugin;
	import org.eclipse.tcf.te.tcf.filesystem.ui.controls.FSTreeContentProvider;
	import org.eclipse.tcf.te.tcf.filesystem.ui.controls.FSTreeViewerSorter;
	import org.eclipse.tcf.te.tcf.filesystem.ui.interfaces.IFSConstants;
	import org.eclipse.tcf.te.tcf.filesystem.ui.internal.ImageConsts;
	import org.eclipse.tcf.te.tcf.filesystem.ui.internal.columns.FSTreeElementLabelProvider;
	import org.eclipse.tcf.te.tcf.filesystem.ui.internal.handlers.MoveFilesHandler;
	import org.eclipse.tcf.te.tcf.filesystem.ui.nls.Messages;
	import org.eclipse.tcf.te.tcf.locator.interfaces.nodes.IPeerNode;
	import org.eclipse.tcf.te.ui.trees.FilterDescriptor;
	import org.eclipse.tcf.te.ui.trees.ViewerStateManager;
	import org.eclipse.ui.IDecoratorManager;
	import org.eclipse.ui.IWorkbench;
	import org.eclipse.ui.PlatformUI;
	import org.eclipse.ui.dialogs.ElementTreeSelectionDialog;
	import org.eclipse.ui.dialogs.ISelectionStatusValidator;

	/**
	* <p>
	* The folder selection dialog for a remote file system. To populate the tree of the selection
	* dialog with the file system, you should call <code>
	* ElementTreeSelectionDialog.setInput</code> to specify the peer model of the remote target. In
	* order to validate the destination folder, you should also specify the nodes to be moved. The file
	* selection dialog is of single selection. You can get the selected result by calling
	* <code>getFirstResult</code>. The type of selected folder is an instance of IFSTreeNode.
	* </p>
	* <p>
	* The following is a snippet of example code:
	*
	* <pre>
	* FSFolderSelectionDialog dialog = new FSFolderSelectionDialog(shell);
	* dialog.setInput(peer);
	* dialog.setMovedNodes(nodes);
	* if (dialog.open() == Window.OK) {
	* Object obj = dialog.getFirstResult();
	* Assert.isTrue(obj instanceof IFSTreeNode);
	* IFSTreeNode folder = (IFSTreeNode) obj;
	* // Use folder ...
	* }
	* </pre>
	*
	* @see MoveFilesHandler
	*/
	public final class FSFolderSelectionDialog extends ElementTreeSelectionDialog {
	// The nodes that are being moved.
	private List<IFSTreeNode> movedNodes;
	private final int mode;

	public static final int MODE_ALL = 0;
	public static final int MODE_ALL_WARNING_NOT_WRITABLE = 1;
	public static final int MODE_ONLY_WRITABLE = 2;

	/**
	* Create an FSFolderSelectionDialog using the specified shell as the parent.
	*
	* @param parentShell The parent shell.
	*/
	public FSFolderSelectionDialog(Shell parentShell) {
	this(parentShell, MODE_ONLY_WRITABLE);
	}

	/**
	* Create an FSFolderSelectionDialog using the specified shell as the parent.
	*
	* @param parentShell The parent shell.
	* @param mode The mode of this dialog.
	*/
	public FSFolderSelectionDialog(Shell parentShell, int mode) {
	this(parentShell, new FSTreeElementLabelProvider(), new FSTreeContentProvider(), mode);
	}

	/**
	* Create an FSFolderSelectionDialog using the specified shell, an FSTreeLabelProvider, and a
	* content provider that provides the tree nodes.
	*
	* @param parentShell The parent shell.
	* @param labelProvider The label provider.
	* @param contentProvider The content provider.
	* @param mode The mode of this dialog.
	*/
	private FSFolderSelectionDialog(Shell parentShell, ILabelProvider labelProvider, ITreeContentProvider contentProvider, int mode) {
	super(parentShell, createDecoratingLabelProvider(labelProvider), contentProvider);
	this.mode = mode;
	setTitle(Messages.FSFolderSelectionDialog_MoveDialogTitle);
	setMessage(Messages.FSFolderSelectionDialog_MoveDialogMessage);
	this.setAllowMultiple(false);
	this.setComparator(new FSTreeViewerSorter());
	this.addFilter(new DirectoryFilter());
	this.setStatusLineAboveButtons(true);
	this.setValidator(new ISelectionStatusValidator() {
	@Override
	public IStatus validate(final Object[] selection) {
	return isValidFolder(selection);
	}
	});
	}

	/**
	* The viewer filter used to filter out files.
	*/
	static class DirectoryFilter extends ViewerFilter {
	@Override
	public boolean select(Viewer viewer, Object parentElement, Object element) {
	if (element instanceof IFSTreeNode) {
	IFSTreeNode node = (IFSTreeNode) element;
	if(node.isFile()) return false;
	}
	return true;
	}
	}

	/*
	* (non-Javadoc)
	* @see org.eclipse.ui.dialogs.ElementTreeSelectionDialog#setInput(java.lang.Object)
	*/
	@Override
	public void setInput(Object input) {
	super.setInput(input);
	FilterDescriptor[] filterDescriptors = ViewerStateManager.getInstance().getFilterDescriptors(IFSConstants.ID_TREE_VIEWER_FS, input);
	Assert.isNotNull(filterDescriptors);
	for (FilterDescriptor descriptor : filterDescriptors) {
	if (descriptor.isEnabled()) {
	addFilter(descriptor.getFilter());
	}
	}
	}

	/**
	* Create a decorating label provider using the specified label provider.
	*
	* @param labelProvider The label provider that actually provides labels and images.
	* @return The decorating label provider.
	*/
	private static ILabelProvider createDecoratingLabelProvider(ILabelProvider labelProvider) {
	IWorkbench workbench = PlatformUI.getWorkbench();
	IDecoratorManager manager = workbench.getDecoratorManager();
	ILabelDecorator decorator = manager.getLabelDecorator();
	return new DecoratingLabelProvider(labelProvider,decorator);
	}

	/**
	* Set the nodes that are about to be moved.
	*
	* @param movedNodes The nodes.
	*/
	public void setMovedNodes(List<IFSTreeNode> movedNodes) {
	this.movedNodes = movedNodes;
	}

	@Override
	public TreeViewer getTreeViewer() {
	return super.getTreeViewer();
	}

	/**
	* Create the tree viewer and set it to the label provider.
	*/
	@Override
	protected TreeViewer doCreateTreeViewer(Composite parent, int style) {
	TreeViewer viewer = super.doCreateTreeViewer(parent, style);

	Button refreshAll = new Button(parent, SWT.PUSH);
	refreshAll.setText(Messages.FSFolderSelectionDialog_RefreshAll_menu);
	refreshAll.addSelectionListener(new SelectionAdapter() {
	@Override
	public void widgetSelected(SelectionEvent e) {
	refreshModel();
	}
	});

	viewer.getTree().addKeyListener(new KeyAdapter() {
	/* (non-Javadoc)
	* @see org.eclipse.swt.events.KeyAdapter#keyReleased(org.eclipse.swt.events.KeyEvent)
	*/
	@Override
	public void keyReleased(KeyEvent e) {
	if (e.keyCode == SWT.F5) {
	refresh();
	}
	}
	});
	viewer.getTree().setLinesVisible(false);

	MenuManager menuMgr = new MenuManager();
	menuMgr.setRemoveAllWhenShown(true);
	menuMgr.addMenuListener(new IMenuListener() {
	@Override
	public void menuAboutToShow(IMenuManager manager) {
	IAction action = new Action(Messages.FSFolderSelectionDialog_Refresh_menu, UIPlugin.getImageDescriptor(ImageConsts.REFRESH_IMAGE)) {
	@Override
	public void run() {
	refresh();
	}
	};
	action.setAccelerator(SWT.F5);
	manager.add(action);
	}
	});
	Menu menu = menuMgr.createContextMenu(viewer.getControl());
	viewer.getControl().setMenu(menu);

	return viewer;
	}

	public void refresh() {
	ISelection sel = getTreeViewer().getSelection();
	if (sel instanceof IStructuredSelection && !sel.isEmpty()) {
	Iterator<Object> it = ((IStructuredSelection)sel).iterator();
	while (it.hasNext()) {
	Object node = it.next();
	if (node instanceof IFSTreeNode) {
	refreshNode((IFSTreeNode)node);
	}
	else {
	refreshModel();
	return;
	}
	}
	}
	else {
	refreshModel();
	}
	}

	protected void refreshNode(final IFSTreeNode treeNode) {
	treeNode.operationRefresh(true).runInJob(null);
	}

	protected void refreshModel() {
	Object input = getTreeViewer().getInput();
	if (input instanceof IPeerNode) {
	IRuntimeModel rtm = ModelManager.getRuntimeModel((IPeerNode)input);
	if (rtm != null)
	refreshNode(rtm.getRoot());
	}
	}


	private final static IStatus error = new Status(IStatus.ERROR, UIPlugin.getUniqueIdentifier(), null);
	private final static IStatus errorNotWritable = new Status(IStatus.ERROR, UIPlugin.getUniqueIdentifier(), Messages.FSFolderSelectionDialog_notWritable_error);
	private final static IStatus warningNotWritable = new Status(IStatus.WARNING, UIPlugin.getUniqueIdentifier(), Messages.FSFolderSelectionDialog_notWritable_warning);

	/**
	* If the specified selection is a valid folder to be selected.
	*
	* @param selection The selected folders.
	* @return An error status if it is invalid or an OK status indicating it is valid.
	*/
	IStatus isValidFolder(Object[] selection) {
	if (selection == null \|\| selection.length == 0) {
	return error;
	}
	if (!(selection[0] instanceof IFSTreeNode)) {
	return error;
	}
	IFSTreeNode target = (IFSTreeNode) selection[0];
	if (movedNodes != null) {
	for (IFSTreeNode node : movedNodes) {
	if (node == target \|\| node.isAncestorOf(target)) {
	return error;
	}
	}
	}
	if(mode != MODE_ALL && !target.isWritable()) {
	return mode == MODE_ONLY_WRITABLE ? errorNotWritable : warningNotWritable;
	}
	return Status.OK_STATUS;
	}
	}