if (selection.isEmpty()) return false;
	public boolean canOperateOnSelection() {		IStructuredSelection selection = getStructuredSelection();		for (Iterator enum = selection.iterator(); enum.hasNext();) {			Object o = enum.next();			if (o instanceof IAdaptable) {				Object resource= ((IAdaptable)o).getAdapter(IResource.class);				if (!(resource instanceof IFile))					return false;			} else {