public Object getData(String dataId) {
   PackageDependenciesNode node = getSelectedNode();
   if (PlatformDataKeys.NAVIGATABLE.is(dataId)) {
     return node;
   }
   if (LangDataKeys.PSI_ELEMENT.is(dataId) && node != null) {
     final PsiElement element = node.getPsiElement();
     return element != null && element.isValid() ? element : null;
   }
   return null;
 }