*     Aleksandra Wozniak (aleksandra.k.wozniak@gmail.com) - Bug 239959

	public static String CompareWithOther_fileLabel;

	public static String CompareWithOther_ancestor;

	public static String CompareWithOther_rightPanel;

	public static String CompareWithOther_leftPanel;

	public static String CompareWithOther_dialogTitle;

	public static String CompareWithOther_dialogMessage;

	public static String CompareWithOther_error_not_comparable;

	public static String CompareWithOther_error_empty;

	public static String CompareWithOther_clear;

	public static String CompareWithOther_warning_two_way;

	public static String CompareWithOther_info;

#     Aleksandra Wozniak (aleksandra.k.wozniak@gmail.com) - Bug 239959

CompareWithOther_fileLabel=File:

CompareWithOther_ancestor=Ancestor

CompareWithOther_rightPanel=Right

CompareWithOther_leftPanel=Left

CompareWithOther_dialogTitle=Compare with Other Resource

CompareWithOther_dialogMessage=Select resources to compare

CompareWithOther_error_not_comparable=Selected resources are not comparable.

CompareWithOther_error_empty=Both left and right panel must contain a valid path.

CompareWithOther_warning_two_way=Ancestor is not a valid resource. Two-way compare will be performed.

CompareWithOther_clear=Clear

CompareWithOther_info=Drag files from a view or between dialog's fields.

 *     Aleksandra Wozniak (aleksandra.k.wozniak@gmail.com) - Bug 239959

import org.eclipse.compare.CompareConfiguration;

import org.eclipse.compare.CompareUI;

 *     Aleksandra Wozniak (aleksandra.k.wozniak@gmail.com) - Bug 239959

		fLeft= getStructure(fLeftResource);

		fRight= getStructure(fRightResource);

		return true;

	}

	private boolean showCompareWithOtherResourceDialog(Shell shell, ISelection s) {

		CompareWithOtherResourceDialog dialog = new CompareWithOtherResourceDialog(shell, s);

		if (dialog.open() != IDialogConstants.OK_ID)

			return false;

		IResource[] selection = dialog.getResult();

		if (!checkSelection(selection))

			return false;

		fThreeWay = selection.length == 3;

		if (fThreeWay) {

			fAncestorResource = selection[0];

			fAncestor = getStructure(fAncestorResource);

			fLeftResource = selection[1];

			fRightResource = selection[2];

		} else {

			fAncestorResource = null;

			fAncestor = null;

			fLeftResource = selection[0];

			fRightResource = selection[1];

		}

         <action

               class="org.eclipse.compare.internal.CompareWithOtherResourceAction"

               enablesFor="+"

               id="compareWithOtherResource"

               label="%CompareWithOtherResource.label"

               menubarPath="compareWithMenu/compareWithGroup"

               tooltip="%CompareWithOtherResourceAction.tooltip">

         </action>

CompareWithOtherResource.label= &Other Resource...

CompareWithOtherResource.tooltip= Open the 'Compare With' Dialog

/*******************************************************************************

 * Copyright (c) 2008 Aleksandra Wozniak 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:

 *    Aleksandra Wozniak (aleksandra.k.wozniak@gmail.com) - initial API and implementation

 *******************************************************************************/

package org.eclipse.compare.internal;

import org.eclipse.jface.viewers.ISelection;

/**

 * The "Compare with other resource" action

 * 

 * @since 3.4

 */

public class CompareWithOtherResourceAction extends CompareAction {

	public void run(ISelection selection) {

		// Show CompareWithOtherResourceDialog which return resources to compare

		// and ancestor if specified. Don't need to display the other dialog

		showSelectAncestorDialog = false;

		super.run(selection);

	}

	protected boolean isEnabled(ISelection selection) {

		// ignore returned value

		super.isEnabled(selection);

		return true;

	}

}

/*******************************************************************************

 * Copyright (c) 2008 Aleksandra Wozniak 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:

 *    Aleksandra Wozniak (aleksandra.k.wozniak@gmail.com) - initial API and implementation

 *******************************************************************************/

package org.eclipse.compare.internal;

import org.eclipse.compare.CompareConfiguration;

import org.eclipse.core.resources.IResource;

import org.eclipse.core.resources.IWorkspaceRoot;

import org.eclipse.core.resources.ResourcesPlugin;

import org.eclipse.jface.dialogs.IDialogConstants;

import org.eclipse.jface.dialogs.IMessageProvider;

import org.eclipse.jface.dialogs.TitleAreaDialog;

import org.eclipse.jface.viewers.ISelection;

import org.eclipse.jface.viewers.StructuredSelection;

import org.eclipse.swt.SWT;

import org.eclipse.swt.dnd.DND;

import org.eclipse.swt.dnd.DragSource;

import org.eclipse.swt.dnd.DragSourceEvent;

import org.eclipse.swt.dnd.DragSourceListener;

import org.eclipse.swt.dnd.DropTarget;

import org.eclipse.swt.dnd.DropTargetEvent;

import org.eclipse.swt.dnd.DropTargetListener;

import org.eclipse.swt.dnd.TextTransfer;

import org.eclipse.swt.dnd.Transfer;

import org.eclipse.swt.events.ModifyEvent;

import org.eclipse.swt.events.ModifyListener;

import org.eclipse.swt.events.SelectionEvent;

import org.eclipse.swt.events.SelectionListener;

import org.eclipse.swt.layout.GridData;

import org.eclipse.swt.layout.GridLayout;

import org.eclipse.swt.widgets.Button;

import org.eclipse.swt.widgets.Composite;

import org.eclipse.swt.widgets.Control;

import org.eclipse.swt.widgets.Group;

import org.eclipse.swt.widgets.Label;

import org.eclipse.swt.widgets.Shell;

import org.eclipse.swt.widgets.Text;

import org.eclipse.ui.forms.events.ExpansionAdapter;

import org.eclipse.ui.forms.events.ExpansionEvent;

import org.eclipse.ui.forms.widgets.ExpandableComposite;

import org.eclipse.ui.part.ResourceTransfer;

/**

 * This is a dialog that can invoke the compare editor on chosen files.

 * 

 * @since 3.4

 */

public class CompareWithOtherResourceDialog extends TitleAreaDialog {

	private int CLEAR_RETURN_CODE = 150; // any number != 0

	private int MIN_WIDTH = 300;

	private int MIN_HEIGHT = 175;

	private class FileTextDragListener implements DragSourceListener {

		private InternalSection section;

		public FileTextDragListener(InternalSection section) {

			this.section = section;

		}

		public void dragFinished(DragSourceEvent event) {

			section.fileText.setText(""); //$NON-NLS-1$

		}

		public void dragSetData(DragSourceEvent event) {

			if (TextTransfer.getInstance().isSupportedType(event.dataType)) {

				event.data = section.fileText.getText();

			} else

				event.data = section.fileText.getText();

		}

		public void dragStart(DragSourceEvent event) {

			if (section.fileText.getText() == null)

				event.doit = false;

		}

	}

	private class FileTextDropListener implements DropTargetListener {

		private InternalSection section;

		private ResourceTransfer resourceTransfer;

		private TextTransfer textTransfer;

		public FileTextDropListener(InternalSection section) {

			this.section = section;

			resourceTransfer = ResourceTransfer.getInstance();

			textTransfer = TextTransfer.getInstance();

		}

		public void dragEnter(DropTargetEvent event) {

			if (event.detail == DND.DROP_DEFAULT) {

				if ((event.operations & DND.DROP_COPY) != 0)

					event.detail = DND.DROP_COPY;

				else

					event.detail = DND.DROP_NONE;

			}

			for (int i = 0; i < event.dataTypes.length; i++) {

				if (resourceTransfer.isSupportedType(event.dataTypes[i])

						|| textTransfer.isSupportedType(event.dataTypes[i])) {

					event.currentDataType = event.dataTypes[i];

					if (event.detail != DND.DROP_COPY)

						event.detail = DND.DROP_NONE;

					break;

				}

			}

		}

		public void dragLeave(DropTargetEvent event) {

			// intentionally empty

		}

		public void dragOperationChanged(DropTargetEvent event) {

			if (event.detail == DND.DROP_DEFAULT) {

				if ((event.operations & DND.DROP_COPY) != 0)

					event.detail = DND.DROP_COPY;

				else

					event.detail = DND.DROP_NONE;

			} else if (resourceTransfer.isSupportedType(event.currentDataType)) {

				if (event.detail != DND.DROP_COPY)

					event.detail = DND.DROP_NONE;

			}

		}

		public void dragOver(DropTargetEvent event) {

			// intentionally empty

		}

		public void drop(DropTargetEvent event) {

			if (textTransfer.isSupportedType(event.currentDataType)) {

				String txt = (String) event.data;

				section.setResource(ResourcesPlugin.getWorkspace().getRoot()

						.findMember(txt));

			} else if (resourceTransfer.isSupportedType(event.currentDataType)) {

				IResource[] files = (IResource[]) event.data;

				section.setResource(files[0]);

			}

			updateErrorInfo();

		}

		public void dropAccept(DropTargetEvent event) {

			// intentionally empty

		}

	}

	private abstract class InternalSection {

		protected Group group;

		protected Text fileText;

		private IResource resource;

		public InternalSection(Composite parent) {

			createContents(parent);

		}

		private InternalSection() {

			// not to instantiate

		}

		public void createContents(Composite parent) {

			createGroup(parent);

			createFileLabel();

			createFileCombo();

			initDrag();

			initDrop();

		}

		public IResource getResource() {

			return resource;

		}

		public void setResource(IResource resource) {

			this.resource = resource;

			String txt = resource.getFullPath().toString();

			fileText.setText(txt);

		}

		public void setResource(String s) {

			IResource tmp = ResourcesPlugin.getWorkspace().getRoot()

					.findMember(s);

			if (tmp instanceof IWorkspaceRoot)

				resource = null;

			else

				resource = tmp;

		}

		protected void clearResource() {

			resource = null;

			fileText.setText(""); //$NON-NLS-1$

			updateErrorInfo();

		}

		protected void initDrag() {

			DragSource source = new DragSource(fileText, DND.DROP_MOVE

					| DND.DROP_COPY | DND.DROP_DEFAULT);

			Transfer[] types = new Transfer[] { TextTransfer.getInstance(),

					ResourceTransfer.getInstance() };

			source.setTransfer(types);

			source.addDragListener(new FileTextDragListener(this));

		}

		protected void initDrop() {

			DropTarget target = new DropTarget(fileText, DND.DROP_MOVE

					| DND.DROP_COPY | DND.DROP_DEFAULT);

			Transfer[] types = new Transfer[] { TextTransfer.getInstance(),

					ResourceTransfer.getInstance() };

			target.setTransfer(types);

			target.addDropListener(new FileTextDropListener(this));

		}

		protected void createGroup(Composite parent) {

			group = new Group(parent, SWT.NONE);

			group.setLayout(new GridLayout(3, false));

			group.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, false));

		}

		protected void createFileCombo() {

			fileText = new Text(group, SWT.BORDER);

			fileText

					.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, false));

			fileText.addModifyListener(new ModifyListener() {

				public void modifyText(ModifyEvent e) {

					setResource(fileText.getText());

					updateErrorInfo();

				}

			});

			fileText.addSelectionListener(new SelectionListener() {

				public void widgetDefaultSelected(SelectionEvent e) {

					widgetSelected(e);

				}

				public void widgetSelected(SelectionEvent e) {

					setResource(fileText.getText());

					updateErrorInfo();

				}

			});

		}

		protected void createFileLabel() {

			final Label fileLabel = new Label(group, SWT.NONE);

			fileLabel.setText(CompareMessages.CompareWithOther_fileLabel);

		}

	}

	private class InternalGroup extends InternalSection {

		public InternalGroup(Composite parent) {

			createContents(parent);

		}

		public void setText(String text) {

			group.setText(text);

		}

		public void setLayoutData(GridData layoutData) {

			group.setLayoutData(layoutData);

		}

	}

	private class InternalExpandable extends InternalSection {

		private ExpandableComposite expandable;

		private Button clearButton;

		public InternalExpandable(Composite parent) {

			createContents(parent);

		}

		public void createContents(Composite parent) {

			createGroup(parent);

			createFileLabel();

			createFileCombo();

			createClearButton(group);

			initDrag();

			initDrop();

		}

		public void createGroup(Composite parent) {

			final Composite p = parent;

			expandable = new ExpandableComposite(parent, SWT.NONE,

					ExpandableComposite.TREE_NODE | ExpandableComposite.TWISTIE);

			super.createGroup(expandable);

			expandable.setClient(group);

			expandable.addExpansionListener(new ExpansionAdapter() {

				public void expansionStateChanged(ExpansionEvent e) {

					p.layout();

				}

			});

		}

		protected void createClearButton(Composite parent) {

			clearButton = createButton(parent, CLEAR_RETURN_CODE,

					CompareMessages.CompareWithOther_clear, false);

			clearButton.addSelectionListener(new SelectionListener() {

				public void widgetDefaultSelected(SelectionEvent e) {

					widgetSelected(e);

				}

				public void widgetSelected(SelectionEvent e) {

					clearResource();

				}

			});

		}

		public void setText(String text) {

			expandable.setText(text);

			group.setText(text);

		}

		public void setLayoutData(GridData layoutData) {

			expandable.setLayoutData(layoutData);

		}

	}

	private Button okButton;

	private InternalGroup rightPanel, leftPanel;

	private InternalExpandable ancestorPanel;

	private ISelection fselection;

	/**

	 * Creates the dialog.

	 * 

	 * @param shell

	 *            a shell

	 * @param selection

	 *            if the selection is not null, it will be set as initial files

	 *            for comparison

	 * @since 3.4

	 */

	protected CompareWithOtherResourceDialog(Shell shell, ISelection selection) {

		super(shell);

		setShellStyle(SWT.MODELESS | SWT.RESIZE | SWT.MAX);

		fselection = selection;

	}

	/*

	 * (non-Javadoc)

	 * 

	 * @see

	 * org.eclipse.jface.dialogs.Dialog#createDialogArea(org.eclipse.swt.widgets

	 * .Composite)

	 */

	protected Control createDialogArea(Composite parent) {

		Composite mainPanel = new Composite(parent, SWT.NULL);

		mainPanel.setLayout(new GridLayout(2, true));

		mainPanel.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));

		ancestorPanel = new InternalExpandable(mainPanel);

		ancestorPanel.setText(CompareMessages.CompareWithOther_ancestor);

		GridData ancestorGD = new GridData(SWT.FILL, SWT.FILL, true, false);

		ancestorGD.horizontalSpan = 2;

		ancestorPanel.setLayoutData(ancestorGD);

		leftPanel = new InternalGroup(mainPanel);

		leftPanel.setText(CompareMessages.CompareWithOther_leftPanel);

		leftPanel.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, false));

		rightPanel = new InternalGroup(mainPanel);

		rightPanel.setText(CompareMessages.CompareWithOther_rightPanel);

		rightPanel.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, false));

		setSelection(fselection);

		getShell().setText(CompareMessages.CompareWithOther_dialogTitle);

		setTitle(CompareMessages.CompareWithOther_dialogMessage);

		getShell().setMinimumSize(convertHorizontalDLUsToPixels(MIN_WIDTH),

				convertVerticalDLUsToPixels(MIN_HEIGHT));

		return mainPanel;

	}

	/*

	 * (non-Javadoc)

	 * 

	 * @see

	 * org.eclipse.jface.dialogs.Dialog#createButtonsForButtonBar(org.eclipse

	 * .swt.widgets.Composite)

	 */

	protected void createButtonsForButtonBar(Composite parent) {

		super.createButtonsForButtonBar(parent);

		okButton = getButton(IDialogConstants.OK_ID);

		updateErrorInfo();

		setMessage(CompareMessages.CompareWithOther_info);

	}

	private void setSelection(ISelection selection) {

		IResource[] selectedResources = Utilities.getResources(selection);

		switch (selectedResources.length) {

		case 1:

			leftPanel.setResource(selectedResources[0]);

			break;

		case 2:

			leftPanel.setResource(selectedResources[0]);

			rightPanel.setResource(selectedResources[1]);

			break;

		case 3:

			ancestorPanel.setResource(selectedResources[0]);

			ancestorPanel.expandable.setExpanded(true);

			leftPanel.setResource(selectedResources[1]);

			rightPanel.setResource(selectedResources[2]);

			break;

		}

	}

	private boolean isComparePossible() {

		IResource[] resources;

		if (ancestorPanel.getResource() == null) {

			resources = new IResource[] { leftPanel.getResource(),

					rightPanel.getResource() };

		} else {

			resources = new IResource[] { ancestorPanel.getResource(),

					leftPanel.getResource(), rightPanel.getResource() };

		}

		ResourceCompareInput r = new ResourceCompareInput(

				new CompareConfiguration());

		return r.isEnabled(new StructuredSelection(resources));

	}

	private void updateErrorInfo() {

		if (okButton != null) {

			if (leftPanel.getResource() == null

					|| rightPanel.getResource() == null) {

				setMessage(CompareMessages.CompareWithOther_error_empty,

						IMessageProvider.ERROR);

				okButton.setEnabled(false);

			} else if (ancestorPanel.getResource() == null

					&& ancestorPanel.fileText.getText() != "") { //$NON-NLS-1$

				setMessage(CompareMessages.CompareWithOther_warning_two_way,

						IMessageProvider.WARNING);

			} else if (!isComparePossible()) {

				setMessage(

						CompareMessages.CompareWithOther_error_not_comparable,

						IMessageProvider.ERROR);

				okButton.setEnabled(false);

			} else {

				setMessage(CompareMessages.CompareWithOther_info);

				okButton.setEnabled(true);

			}

		}

	}

	/**

	 * Returns table with selected resources. If any resource wasn't chosen in

	 * the ancestor panel, table has only two elements -- resources chosen in

	 * left and right panel. In the other case table contains all three

	 * resources.

	 * 

	 * @return table with selected resources

	 */

	public IResource[] getResult() {

		IResource[] resources;

		IResource rightResource = rightPanel.getResource();

		IResource leftResource = leftPanel.getResource();

		IResource ancestorResource = ancestorPanel.getResource();

		if (ancestorResource == null)

			resources = new IResource[] { leftResource, rightResource };

		else

			resources = new IResource[] { ancestorResource, leftResource,

					rightResource };

		return resources;

	}

}