org.eclipse.jdt.ui/ui refactoring/org/eclipse/jdt/internal/ui/refactoring/UseSupertypeWizard.java - jdt/eclipse.jdt.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2011 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.jdt.internal.ui.refactoring;

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

 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 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.Label;
 import org.eclipse.swt.widgets.Tree;
 import org.eclipse.swt.widgets.TreeItem;

 import org.eclipse.jface.dialogs.Dialog;
 import org.eclipse.jface.dialogs.IDialogSettings;
 import org.eclipse.jface.dialogs.IMessageProvider;
 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.ViewerComparator;
 import org.eclipse.jface.wizard.IWizardPage;

 import org.eclipse.ui.PlatformUI;

 import org.eclipse.ltk.core.refactoring.Refactoring;
 import org.eclipse.ltk.ui.refactoring.RefactoringWizard;
 import org.eclipse.ltk.ui.refactoring.UserInputWizardPage;

 import org.eclipse.jdt.core.IType;
 import org.eclipse.jdt.core.ITypeHierarchy;
 import org.eclipse.jdt.core.JavaModelException;

 import org.eclipse.jdt.internal.corext.refactoring.structure.UseSuperTypeProcessor;
 import org.eclipse.jdt.internal.corext.util.Messages;
 import org.eclipse.jdt.internal.corext.util.SuperTypeHierarchyCache;

 import org.eclipse.jdt.ui.JavaElementLabelProvider;
 import org.eclipse.jdt.ui.JavaElementLabels;

 import org.eclipse.jdt.internal.ui.IJavaHelpContextIds;
 import org.eclipse.jdt.internal.ui.JavaPlugin;

 public class UseSupertypeWizard extends RefactoringWizard{

 	/* package */ static final String DIALOG_SETTING_SECTION= "UseSupertypeWizard"; //$NON-NLS-1$
 	private final UseSuperTypeProcessor fProcessor;

 	public UseSupertypeWizard(UseSuperTypeProcessor processor, Refactoring ref) {
 		super(ref, DIALOG_BASED_USER_INTERFACE);
 		fProcessor= processor;
 		setDefaultPageTitle(RefactoringMessages.UseSupertypeWizard_Use_Super_Type_Where_Possible);
 	}

 	@Override
 	protected void addUserInputPages(){
 		addPage(new UseSupertypeInputPage(fProcessor));
 	}

 	private static class UseSupertypeInputPage extends UserInputWizardPage{

 		private static class UseSupertypeContentProvider implements ITreeContentProvider {

 			private ITypeHierarchy fHierarchy;

 			@Override
 			public Object[] getChildren(Object element) {
 				if (element instanceof ITypeHierarchy)
 					return getElements(element);
 				return getDirectSuperTypes((IType)element).toArray();
 			}

 			public Set<IType> getDirectSuperTypes(IType type){
 				Set<IType> result= new HashSet<>();
 				final IType superclass= fHierarchy.getSuperclass(type);
 				if (superclass != null) {
 					result.add(superclass);
 				}
 				IType[] superInterface= fHierarchy.getSuperInterfaces(type);
 				result.addAll(Arrays.asList(superInterface));
 				try {
 					if (type.isInterface()) {
 						IType found= type.getJavaProject().findType("java.lang.Object"); //$NON-NLS-1$
 						result.add(found);
 					}
 				} catch (JavaModelException exception) {
 					JavaPlugin.log(exception);
 				}
 				return result;
 			}

 			@Override
 			public Object[] getElements(Object element) {
 				if (element instanceof ITypeHierarchy)
 					return getChildren(((ITypeHierarchy) element).getType());
 				return new Object[0];
 			}

 			@Override
 			public boolean hasChildren(Object element) {
 				return getChildren(element).length > 0;
 			}

 			@Override
 			public Object getParent(Object element) {
 				return null;
 			}

 			@Override
 			public void dispose() {
 				// Do nothing
 			}

 			@Override
 			public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
 				if (newInput instanceof ITypeHierarchy)
 					fHierarchy= (ITypeHierarchy) newInput;
 				else
 					fHierarchy= null;
 			}
 		}

 		private static final String REWRITE_INSTANCEOF= "rewriteInstanceOf";  //$NON-NLS-1$
 		public static final String PAGE_NAME= "UseSupertypeInputPage";//$NON-NLS-1$
 		private TreeViewer fTreeViewer;
 		private final Map<IType, Integer> fFileCount;  //IType -> Integer
 		private final static String MESSAGE= RefactoringMessages.UseSupertypeInputPage_Select_supertype;
 		private JavaElementLabelProvider fLabelProvider;
 		private IDialogSettings fSettings;
 		private UseSuperTypeProcessor fProcessor;

 		public UseSupertypeInputPage(UseSuperTypeProcessor processor) {
 			super(PAGE_NAME);
 			fFileCount= new HashMap<>(2);
 			fProcessor= processor;
 			setMessage(MESSAGE);
 		}

 		private void loadSettings() {
 			fSettings= getDialogSettings().getSection(UseSupertypeWizard.DIALOG_SETTING_SECTION);
 			if (fSettings == null) {
 				fSettings= getDialogSettings().addNewSection(UseSupertypeWizard.DIALOG_SETTING_SECTION);
 				fSettings.put(REWRITE_INSTANCEOF, false);
 			}
 			getUseSupertypeProcessor().setInstanceOf(fSettings.getBoolean(REWRITE_INSTANCEOF));
 		}

 		private UseSuperTypeProcessor getUseSupertypeProcessor() {
 			return fProcessor;
 		}

 		@Override
 		public void createControl(Composite parent) {
 			initializeDialogUnits(parent);
 			loadSettings();
 			Composite composite= new Composite(parent, SWT.NONE);
 			setControl(composite);
 			composite.setLayout(new GridLayout());

 			Label label= new Label(composite, SWT.NONE);
 			label.setText(Messages.format(
 					RefactoringMessages.UseSupertypeInputPage_Select_supertype_to_use,
 					JavaElementLabels.getElementLabel(getUseSupertypeProcessor().getSubType(), JavaElementLabels.T_FULLY_QUALIFIED)));
 			label.setLayoutData(new GridData());

 			addTreeViewer(composite);

 			final Button checkbox= new Button(composite, SWT.CHECK);
 			checkbox.setText(RefactoringMessages.UseSupertypeInputPage_Use_in_instanceof);
 			checkbox.setLayoutData(new GridData());
 			checkbox.setSelection(getUseSupertypeProcessor().isInstanceOf());
 			checkbox.addSelectionListener(new SelectionAdapter(){
 				@Override
 				public void widgetSelected(SelectionEvent e) {
 					getUseSupertypeProcessor().setInstanceOf(checkbox.getSelection());
 					fSettings.put(REWRITE_INSTANCEOF, checkbox.getSelection());
 					setMessage(MESSAGE);
 					setPageComplete(true);
 					fFileCount.clear();
 					fTreeViewer.refresh();
 				}
 			});

 			Dialog.applyDialogFont(composite);
 			PlatformUI.getWorkbench().getHelpSystem().setHelp(getControl(), IJavaHelpContextIds.USE_SUPERTYPE_WIZARD_PAGE);
 		}

 		private void addTreeViewer(Composite composite) {
 			fTreeViewer= new TreeViewer(composite, SWT.SINGLE | SWT.BORDER | SWT.V_SCROLL | SWT.H_SCROLL);
 			final Tree tree= fTreeViewer.getTree();
 			final GridData data= new GridData(GridData.FILL_BOTH);
 			data.heightHint= convertHeightInCharsToPixels(12);
 			tree.setLayoutData(data);
 			fLabelProvider= new UseSupertypeLabelProvider(fFileCount);
 			fTreeViewer.setLabelProvider(fLabelProvider);
 			fTreeViewer.setContentProvider(new UseSupertypeContentProvider());
 			fTreeViewer.setComparator(new ViewerComparator() {

 				@Override
 				public boolean isSorterProperty(Object element, String property) {
 					return true;
 				}

 				@Override
 				public int compare(Viewer viewer, Object first, Object second) {
 					final IType type1= (IType)first;
 					final IType type2= (IType)second;
 					try {
 						final int kind1= type1.isInterface() ? 1 : 0;
 						final int kind2= type2.isInterface() ? 1 : 0;
 						if (kind1 - kind2 != 0)
 							return kind1 - kind2;
 					} catch (JavaModelException exception) {
 						JavaPlugin.log(exception);
 					}
 					return getComparator().compare(type1.getElementName(), type2.getElementName());
 				}
 			});
 			fTreeViewer.addSelectionChangedListener(event -> {
 				IStructuredSelection ss= (IStructuredSelection)event.getSelection();
 				if (Integer.valueOf(0).equals(fFileCount.get(ss.getFirstElement()))){
 					setMessage(RefactoringMessages.UseSupertypeInputPage_No_updates, IMessageProvider.INFORMATION);
 					setPageComplete(false);
 				} else {
 					setMessage(MESSAGE);
 					setPageComplete(true);
 				}
 				fTreeViewer.refresh();
 			});
 			try {
 				fTreeViewer.setInput(SuperTypeHierarchyCache.getTypeHierarchy(getUseSupertypeProcessor().getSubType()));
 			} catch (JavaModelException exception) {
 				JavaPlugin.log(exception);
 			}
 			fTreeViewer.expandAll();
 			final TreeItem[] items= tree.getItems();
 			if (items.length > 0)
 				tree.setSelection(new TreeItem[] {items[0]});
 		}

 		@Override
 		public IWizardPage getNextPage() {
 			initializeRefactoring();
 			IWizardPage nextPage= super.getNextPage();
 			updateUpdateLabels();
 			return nextPage;
 		}

 		private void updateUpdateLabels() {
 			IType selectedType= getSelectedSupertype();
 			final int count= getUseSupertypeProcessor().getChanges();
 			fFileCount.put(selectedType, count);
 			if (count == 0) {
 				setMessage(RefactoringMessages.UseSupertypeInputPage_No_updates, IMessageProvider.INFORMATION);
 				setPageComplete(false);
 			}
 			fTreeViewer.refresh();
 			if (noSupertypeCanBeUsed()){
 				setMessage(RefactoringMessages.UseSupertypeWizard_10, IMessageProvider.INFORMATION);
 				setPageComplete(false);
 			}
 		}

 		private boolean noSupertypeCanBeUsed() {
 			return fTreeViewer.getTree().getItemCount() == countFilesWithValue(0);
 		}

 		private int countFilesWithValue(int i) {
 			int count= 0;
 			for (Map.Entry<IType, Integer> entry : fFileCount.entrySet()) {
 				if (entry.getValue().intValue() == i)
 					count++;
 			}
 			return count;
 		}

 		private IType getSelectedSupertype() {
 			IStructuredSelection ss= (IStructuredSelection)fTreeViewer.getSelection();
 			return (IType)ss.getFirstElement();
 		}

 		@Override
 		public boolean performFinish(){
 			initializeRefactoring();
 			boolean superFinish= super.performFinish();
 			if (! superFinish)
 				return false;
 			final int count= getUseSupertypeProcessor().getChanges();
 			if (count == 0) {
 				updateUpdateLabels();
 				return false;
 			}
 			return superFinish;
 		}

 		private void initializeRefactoring() {
 			IStructuredSelection ss= (IStructuredSelection)fTreeViewer.getSelection();
 			getUseSupertypeProcessor().setSuperType((IType)ss.getFirstElement());
 		}

 		@Override
 		public void dispose() {
 			fTreeViewer= null;
 			fFileCount.clear();
 			fLabelProvider= null;
 			super.dispose();
 		}

 		private static class UseSupertypeLabelProvider extends JavaElementLabelProvider{
 			private final Map<IType, Integer> fFileCount;
 			private UseSupertypeLabelProvider(Map<IType, Integer> fileCount){
 				fFileCount= fileCount;
 			}
 			@Override
 			public String getText(Object element) {
 				String superText= super.getText(element);
 				if  (! fFileCount.containsKey(element))
 					return superText;
 				int count= fFileCount.get(element);
 				switch (count) {
 				case 0:
 				{
 					String[] keys= {superText};
 					return Messages.format(RefactoringMessages.UseSupertypeInputPage_no_possible_updates, keys);
 				}
 				case 1:
 				{
 					String [] keys= {superText};
 					return Messages.format(RefactoringMessages.UseSupertypeInputPage_updates_possible_in_file, keys);
 				}
 				default:
 				{
 					String[] keys= {superText, String.valueOf(count)};
 					return Messages.format(RefactoringMessages.UseSupertypeInputPage_updates_possible_in_files, keys);
 				}
 				}
 			}
 		}

 		@Override
 		public void setVisible(boolean visible) {
 			super.setVisible(visible);
 			if (visible && fTreeViewer != null)
 				fTreeViewer.getTree().setFocus();
 		}
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2011 IBM Corporation and others.
	*
	* This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License 2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.jdt.internal.ui.refactoring;

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

	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	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.Label;
	import org.eclipse.swt.widgets.Tree;
	import org.eclipse.swt.widgets.TreeItem;

	import org.eclipse.jface.dialogs.Dialog;
	import org.eclipse.jface.dialogs.IDialogSettings;
	import org.eclipse.jface.dialogs.IMessageProvider;
	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.ViewerComparator;
	import org.eclipse.jface.wizard.IWizardPage;

	import org.eclipse.ui.PlatformUI;

	import org.eclipse.ltk.core.refactoring.Refactoring;
	import org.eclipse.ltk.ui.refactoring.RefactoringWizard;
	import org.eclipse.ltk.ui.refactoring.UserInputWizardPage;

	import org.eclipse.jdt.core.IType;
	import org.eclipse.jdt.core.ITypeHierarchy;
	import org.eclipse.jdt.core.JavaModelException;

	import org.eclipse.jdt.internal.corext.refactoring.structure.UseSuperTypeProcessor;
	import org.eclipse.jdt.internal.corext.util.Messages;
	import org.eclipse.jdt.internal.corext.util.SuperTypeHierarchyCache;

	import org.eclipse.jdt.ui.JavaElementLabelProvider;
	import org.eclipse.jdt.ui.JavaElementLabels;

	import org.eclipse.jdt.internal.ui.IJavaHelpContextIds;
	import org.eclipse.jdt.internal.ui.JavaPlugin;

	public class UseSupertypeWizard extends RefactoringWizard{

	/* package */ static final String DIALOG_SETTING_SECTION= "UseSupertypeWizard"; //$NON-NLS-1$
	private final UseSuperTypeProcessor fProcessor;

	public UseSupertypeWizard(UseSuperTypeProcessor processor, Refactoring ref) {
	super(ref, DIALOG_BASED_USER_INTERFACE);
	fProcessor= processor;
	setDefaultPageTitle(RefactoringMessages.UseSupertypeWizard_Use_Super_Type_Where_Possible);
	}

	@Override
	protected void addUserInputPages(){
	addPage(new UseSupertypeInputPage(fProcessor));
	}

	private static class UseSupertypeInputPage extends UserInputWizardPage{

	private static class UseSupertypeContentProvider implements ITreeContentProvider {

	private ITypeHierarchy fHierarchy;

	@Override
	public Object[] getChildren(Object element) {
	if (element instanceof ITypeHierarchy)
	return getElements(element);
	return getDirectSuperTypes((IType)element).toArray();
	}

	public Set<IType> getDirectSuperTypes(IType type){
	Set<IType> result= new HashSet<>();
	final IType superclass= fHierarchy.getSuperclass(type);
	if (superclass != null) {
	result.add(superclass);
	}
	IType[] superInterface= fHierarchy.getSuperInterfaces(type);
	result.addAll(Arrays.asList(superInterface));
	try {
	if (type.isInterface()) {
	IType found= type.getJavaProject().findType("java.lang.Object"); //$NON-NLS-1$
	result.add(found);
	}
	} catch (JavaModelException exception) {
	JavaPlugin.log(exception);
	}
	return result;
	}

	@Override
	public Object[] getElements(Object element) {
	if (element instanceof ITypeHierarchy)
	return getChildren(((ITypeHierarchy) element).getType());
	return new Object[0];
	}

	@Override
	public boolean hasChildren(Object element) {
	return getChildren(element).length > 0;
	}

	@Override
	public Object getParent(Object element) {
	return null;
	}

	@Override
	public void dispose() {
	// Do nothing
	}

	@Override
	public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
	if (newInput instanceof ITypeHierarchy)
	fHierarchy= (ITypeHierarchy) newInput;
	else
	fHierarchy= null;
	}
	}

	private static final String REWRITE_INSTANCEOF= "rewriteInstanceOf"; //$NON-NLS-1$
	public static final String PAGE_NAME= "UseSupertypeInputPage";//$NON-NLS-1$
	private TreeViewer fTreeViewer;
	private final Map<IType, Integer> fFileCount; //IType -> Integer
	private final static String MESSAGE= RefactoringMessages.UseSupertypeInputPage_Select_supertype;
	private JavaElementLabelProvider fLabelProvider;
	private IDialogSettings fSettings;
	private UseSuperTypeProcessor fProcessor;

	public UseSupertypeInputPage(UseSuperTypeProcessor processor) {
	super(PAGE_NAME);
	fFileCount= new HashMap<>(2);
	fProcessor= processor;
	setMessage(MESSAGE);
	}

	private void loadSettings() {
	fSettings= getDialogSettings().getSection(UseSupertypeWizard.DIALOG_SETTING_SECTION);
	if (fSettings == null) {
	fSettings= getDialogSettings().addNewSection(UseSupertypeWizard.DIALOG_SETTING_SECTION);
	fSettings.put(REWRITE_INSTANCEOF, false);
	}
	getUseSupertypeProcessor().setInstanceOf(fSettings.getBoolean(REWRITE_INSTANCEOF));
	}

	private UseSuperTypeProcessor getUseSupertypeProcessor() {
	return fProcessor;
	}

	@Override
	public void createControl(Composite parent) {
	initializeDialogUnits(parent);
	loadSettings();
	Composite composite= new Composite(parent, SWT.NONE);
	setControl(composite);
	composite.setLayout(new GridLayout());

	Label label= new Label(composite, SWT.NONE);
	label.setText(Messages.format(
	RefactoringMessages.UseSupertypeInputPage_Select_supertype_to_use,
	JavaElementLabels.getElementLabel(getUseSupertypeProcessor().getSubType(), JavaElementLabels.T_FULLY_QUALIFIED)));
	label.setLayoutData(new GridData());

	addTreeViewer(composite);

	final Button checkbox= new Button(composite, SWT.CHECK);
	checkbox.setText(RefactoringMessages.UseSupertypeInputPage_Use_in_instanceof);
	checkbox.setLayoutData(new GridData());
	checkbox.setSelection(getUseSupertypeProcessor().isInstanceOf());
	checkbox.addSelectionListener(new SelectionAdapter(){
	@Override
	public void widgetSelected(SelectionEvent e) {
	getUseSupertypeProcessor().setInstanceOf(checkbox.getSelection());
	fSettings.put(REWRITE_INSTANCEOF, checkbox.getSelection());
	setMessage(MESSAGE);
	setPageComplete(true);
	fFileCount.clear();
	fTreeViewer.refresh();
	}
	});

	Dialog.applyDialogFont(composite);
	PlatformUI.getWorkbench().getHelpSystem().setHelp(getControl(), IJavaHelpContextIds.USE_SUPERTYPE_WIZARD_PAGE);
	}

	private void addTreeViewer(Composite composite) {
	fTreeViewer= new TreeViewer(composite, SWT.SINGLE \| SWT.BORDER \| SWT.V_SCROLL \| SWT.H_SCROLL);
	final Tree tree= fTreeViewer.getTree();
	final GridData data= new GridData(GridData.FILL_BOTH);
	data.heightHint= convertHeightInCharsToPixels(12);
	tree.setLayoutData(data);
	fLabelProvider= new UseSupertypeLabelProvider(fFileCount);
	fTreeViewer.setLabelProvider(fLabelProvider);
	fTreeViewer.setContentProvider(new UseSupertypeContentProvider());
	fTreeViewer.setComparator(new ViewerComparator() {

	@Override
	public boolean isSorterProperty(Object element, String property) {
	return true;
	}

	@Override
	public int compare(Viewer viewer, Object first, Object second) {
	final IType type1= (IType)first;
	final IType type2= (IType)second;
	try {
	final int kind1= type1.isInterface() ? 1 : 0;
	final int kind2= type2.isInterface() ? 1 : 0;
	if (kind1 - kind2 != 0)
	return kind1 - kind2;
	} catch (JavaModelException exception) {
	JavaPlugin.log(exception);
	}
	return getComparator().compare(type1.getElementName(), type2.getElementName());
	}
	});
	fTreeViewer.addSelectionChangedListener(event -> {
	IStructuredSelection ss= (IStructuredSelection)event.getSelection();
	if (Integer.valueOf(0).equals(fFileCount.get(ss.getFirstElement()))){
	setMessage(RefactoringMessages.UseSupertypeInputPage_No_updates, IMessageProvider.INFORMATION);
	setPageComplete(false);
	} else {
	setMessage(MESSAGE);
	setPageComplete(true);
	}
	fTreeViewer.refresh();
	});
	try {
	fTreeViewer.setInput(SuperTypeHierarchyCache.getTypeHierarchy(getUseSupertypeProcessor().getSubType()));
	} catch (JavaModelException exception) {
	JavaPlugin.log(exception);
	}
	fTreeViewer.expandAll();
	final TreeItem[] items= tree.getItems();
	if (items.length > 0)
	tree.setSelection(new TreeItem[] {items[0]});
	}

	@Override
	public IWizardPage getNextPage() {
	initializeRefactoring();
	IWizardPage nextPage= super.getNextPage();
	updateUpdateLabels();
	return nextPage;
	}

	private void updateUpdateLabels() {
	IType selectedType= getSelectedSupertype();
	final int count= getUseSupertypeProcessor().getChanges();
	fFileCount.put(selectedType, count);
	if (count == 0) {
	setMessage(RefactoringMessages.UseSupertypeInputPage_No_updates, IMessageProvider.INFORMATION);
	setPageComplete(false);
	}
	fTreeViewer.refresh();
	if (noSupertypeCanBeUsed()){
	setMessage(RefactoringMessages.UseSupertypeWizard_10, IMessageProvider.INFORMATION);
	setPageComplete(false);
	}
	}

	private boolean noSupertypeCanBeUsed() {
	return fTreeViewer.getTree().getItemCount() == countFilesWithValue(0);
	}

	private int countFilesWithValue(int i) {
	int count= 0;
	for (Map.Entry<IType, Integer> entry : fFileCount.entrySet()) {
	if (entry.getValue().intValue() == i)
	count++;
	}
	return count;
	}

	private IType getSelectedSupertype() {
	IStructuredSelection ss= (IStructuredSelection)fTreeViewer.getSelection();
	return (IType)ss.getFirstElement();
	}

	@Override
	public boolean performFinish(){
	initializeRefactoring();
	boolean superFinish= super.performFinish();
	if (! superFinish)
	return false;
	final int count= getUseSupertypeProcessor().getChanges();
	if (count == 0) {
	updateUpdateLabels();
	return false;
	}
	return superFinish;
	}

	private void initializeRefactoring() {
	IStructuredSelection ss= (IStructuredSelection)fTreeViewer.getSelection();
	getUseSupertypeProcessor().setSuperType((IType)ss.getFirstElement());
	}

	@Override
	public void dispose() {
	fTreeViewer= null;
	fFileCount.clear();
	fLabelProvider= null;
	super.dispose();
	}

	private static class UseSupertypeLabelProvider extends JavaElementLabelProvider{
	private final Map<IType, Integer> fFileCount;
	private UseSupertypeLabelProvider(Map<IType, Integer> fileCount){
	fFileCount= fileCount;
	}
	@Override
	public String getText(Object element) {
	String superText= super.getText(element);
	if (! fFileCount.containsKey(element))
	return superText;
	int count= fFileCount.get(element);
	switch (count) {
	case 0:
	{
	String[] keys= {superText};
	return Messages.format(RefactoringMessages.UseSupertypeInputPage_no_possible_updates, keys);
	}
	case 1:
	{
	String [] keys= {superText};
	return Messages.format(RefactoringMessages.UseSupertypeInputPage_updates_possible_in_file, keys);
	}
	default:
	{
	String[] keys= {superText, String.valueOf(count)};
	return Messages.format(RefactoringMessages.UseSupertypeInputPage_updates_possible_in_files, keys);
	}
	}
	}
	}

	@Override
	public void setVisible(boolean visible) {
	super.setVisible(visible);
	if (visible && fTreeViewer != null)
	fTreeViewer.getTree().setFocus();
	}
	}
	}