How to use org.eclipse.ltk.ui.refactoring.model

@Override
public boolean hasChildren(final Object element) {
  if (element instanceof ICompilationUnit || element instanceof IFile || element instanceof RefactoringDescriptorProxy || element instanceof RefactoringDescriptor)
    return false;
  return super.hasChildren(element);
}

/**
 * {@inheritDoc}
 */
protected void initializeOpenActions() {
  if (!hasRefactorings(getSynchronizationContext(), getSynchronizePageConfiguration()))
    super.initializeOpenActions();
}

@Override
public ICompareInput asCompareInput(final ISynchronizationContext context, final Object element) {
  if (element instanceof RefactoringDescriptorProxy)
    return super.asCompareInput(context, element);
  final IResource resource= JavaModelProvider.getResource(element);
  if (resource != null)
    return super.asCompareInput(context, resource);
  return null;
}

/**
 * Since the this content provider overrides the resource content provider,
 * this method is only invoked when the resource content provider is
 * disabled. In this case, we still want the Java projects to appear at the
 * root of the view.
 * 
 * {@inheritDoc}
 */
public Object[] getElements(Object parent) {
  if (parent instanceof ISynchronizationContext)
    // Put the resource projects directly under the context
    parent= getModelRoot();
  return super.getElements(parent);
}

/**
 * {@inheritDoc}
 */
public void dispose() {
  if (fPackageImage != null && !fPackageImage.isDisposed())
    fPackageImage.dispose();
  if (fLabelProvider != null)
    fLabelProvider.dispose();
  super.dispose();
}

@Override
protected Object[] getChildrenInContext(final ISynchronizationContext context, final Object parent, final Object[] children) {
  final Object[] elements= super.getChildrenInContext(context, parent, children);
  if (parent instanceof IPackageFragment)
    return getPackageFragmentChildren(context, parent, elements);
  else if (parent instanceof IPackageFragmentRoot)
    return getPackageFragmentRootChildren(context, parent, elements);
  else if (parent instanceof IJavaProject)
    return getJavaProjectChildren(context, parent, elements);
  else if (parent instanceof RefactoringHistory)
    return ((RefactoringHistory) parent).getDescriptors();
  // It may be the case that the elements are folders that have a corresponding
  // source folder in which case they should be filtered out
  return getFilteredElements(parent, elements);
}

/**
 * {@inheritDoc}
 */
protected void initialize() {
  super.initialize();
  final ISynchronizePageConfiguration configuration= getSynchronizePageConfiguration();
  registerHandler(MERGE_ACTION_ID, new RefactoringHandlerDelegate(MergeActionHandler.getDefaultHandler(MERGE_ACTION_ID, configuration)));
  registerHandler(OVERWRITE_ACTION_ID, new RefactoringHandlerDelegate(MergeActionHandler.getDefaultHandler(OVERWRITE_ACTION_ID, configuration)));
  registerHandler(MARK_AS_MERGE_ACTION_ID, new RefactoringHandlerDelegate(MergeActionHandler.getDefaultHandler(MARK_AS_MERGE_ACTION_ID, configuration)));
}

@Override
public Image getDelegateImage(final Object element) {
  if (element instanceof IPackageFragment) {
    final IPackageFragment fragment= (IPackageFragment) element;
    final IResource resource= fragment.getResource();
    if (resource == null || !resource.exists()) {
      if (fPackageImage == null)
        fPackageImage= JavaPluginImages.DESC_OBJS_PACKAGE.createImage();
      return fPackageImage;
    }
  }
  return super.getDelegateImage(element);
}

/**
 * {@inheritDoc}
 */
protected IDiff getDiff(final Object element) {
  if (element instanceof RefactoringDescriptorProxy)
    return new RefactoringDescriptorDiff((RefactoringDescriptorProxy) element, getKind(element), getDirection(element));
  else if (element instanceof RefactoringHistory)
    return new RefactoringHistoryDiff((RefactoringHistory) element, getKind(element), getDirection(element));
  return super.getDiff(element);
}

  public final void run() {
    if (MessageDialog.openQuestion(shell, RefactoringUIMessages.RefactoringWizard_refactoring, RefactoringUIMessages.AbstractRefactoringModelMerger_accept_question)) {
      final RefactoringHistoryMergeWizard wizard= new RefactoringHistoryModelMergeWizard();
      int result= Window.OK;
      try {
        wizard.setConfiguration(new RefactoringHistoryModelMergeConfiguration((projects != null && projects.length == 1) ? projects[0] : null));
        wizard.setInput(history);
        result= new WizardDialog(shell, wizard).open();
      } finally {
        if (result != Window.CANCEL)
          wizard.resolveConflicts(context);
      }
    }
  }
});

/**
 * {@inheritDoc}
 */
public ICompareInput asCompareInput(final ISynchronizationContext context, final Object element) {
  if (element instanceof RefactoringDescriptorProxy)
    return new RefactoringDescriptorCompareInput((RefactoringDescriptorProxy) element, getKind(context, (RefactoringDescriptorProxy) element));
  return super.asCompareInput(context, element);
}

@Override
public boolean hasChildren(final Object element) {
  if (element instanceof ICompilationUnit || element instanceof IFile || element instanceof RefactoringDescriptorProxy || element instanceof RefactoringDescriptor)
    return false;
  return super.hasChildren(element);
}

@Override
public ICompareInput asCompareInput(final ISynchronizationContext context, final Object element) {
  if (element instanceof RefactoringDescriptorProxy)
    return super.asCompareInput(context, element);
  final IResource resource= JavaModelProvider.getResource(element);
  if (resource != null)
    return super.asCompareInput(context, resource);
  return null;
}

/**
 * Since the this content provider overrides the resource content provider,
 * this method is only invoked when the resource content provider is
 * disabled. In this case, we still want the Java projects to appear at the
 * root of the view.
 *
 * {@inheritDoc}
 */
@Override
public Object[] getElements(Object parent) {
  if (parent instanceof ISynchronizationContext)
    // Put the resource projects directly under the context
    parent= getModelRoot();
  return super.getElements(parent);
}

@Override
public void dispose() {
  if (fPackageImage != null && !fPackageImage.isDisposed())
    fPackageImage.dispose();
  if (fLabelProvider != null)
    fLabelProvider.dispose();
  super.dispose();
}

@Override
protected Object[] getChildrenInContext(final ISynchronizationContext context, final Object parent, final Object[] children) {
  final Object[] elements= super.getChildrenInContext(context, parent, children);
  if (parent instanceof IPackageFragment)
    return getPackageFragmentChildren(context, parent, elements);
  else if (parent instanceof IPackageFragmentRoot)
    return getPackageFragmentRootChildren(context, parent, elements);
  else if (parent instanceof IJavaProject)
    return getJavaProjectChildren(context, parent, elements);
  else if (parent instanceof RefactoringHistory)
    return ((RefactoringHistory) parent).getDescriptors();
  // It may be the case that the elements are folders that have a corresponding
  // source folder in which case they should be filtered out
  return getFilteredElements(parent, elements);
}

/**
 * {@inheritDoc}
 */
public boolean hasChildren(final Object element) {
  if (element instanceof ICompilationUnit || element instanceof IFile || element instanceof RefactoringDescriptorProxy || element instanceof RefactoringDescriptor)
    return false;
  return super.hasChildren(element);
}

/**
 * {@inheritDoc}
 */
public ICompareInput asCompareInput(final ISynchronizationContext context, final Object element) {
  if (element instanceof RefactoringDescriptorProxy)
    return super.asCompareInput(context, element);
  final IResource resource= JavaModelProvider.getResource(element);
  if (resource != null)
    return super.asCompareInput(context, resource);
  return null;
}

/**
 * Since the this content provider overrides the resource content provider,
 * this method is only invoked when the resource content provider is
 * disabled. In this case, we still want the Java projects to appear at the
 * root of the view.
 *
 * {@inheritDoc}
 */
@Override
public Object[] getElements(Object parent) {
  if (parent instanceof ISynchronizationContext)
    // Put the resource projects directly under the context
    parent= getModelRoot();
  return super.getElements(parent);
}

@Override
public void dispose() {
  if (fPackageImage != null && !fPackageImage.isDisposed())
    fPackageImage.dispose();
  if (fLabelProvider != null)
    fLabelProvider.dispose();
  super.dispose();
}