Bug 93400 LTK UI should provide official API for structural content in the preview page
org.eclipse.ltk.ui.refactoring/src/org/eclipse/ltk/internal/ui/refactoring/ChangeElementLabelProvider.java
Object element= ((DefaultChangeElement)object).getChange();
			return doGetImage(element);
		} else if (object instanceof TextEditChangeElement) {
			Object element= ((TextEditChangeElement)object).getChangeGroup();
			return doGetImage(element);
		} else if (object instanceof ChangeElement) {
			Object modifiedElement= ((ChangeElement)object).getModifiedElement();
			if (modifiedElement instanceof IAdaptable) {
				IWorkbenchAdapter adapter= (IWorkbenchAdapter)((IAdaptable)modifiedElement).getAdapter(IWorkbenchAdapter.class);
				if (adapter != null) {
					return manageImageDescriptor(adapter.getImageDescriptor(modifiedElement));
				}
			}
		}
		return super.getImage(object);
	}
	
	public String getText(Object object) {
		if (object instanceof DefaultChangeElement) {
			Change change= ((DefaultChangeElement)object).getChange();
			if (!fShowQualification)
				return change.getName();
			
			if (change instanceof TextFileChange) {
				IFile file= ((TextFileChange)change).getFile();
				return Messages.format(
					RefactoringUIMessages.PreviewWizardPage_changeElementLabelProvider_textFormat,
					new String[] {file.getName(), getPath(file)});
			} else {
				return change.getName();