@Nullable
  private MPSTreeNode getNode(MPSTreeNode rootTreeNode, VirtualFile file) {
    if (rootTreeNode instanceof AbstractFileTreeNode) {
      VirtualFile nodeFile = ((AbstractFileTreeNode) rootTreeNode).getFile();

      if (nodeFile != null) {
        if (nodeFile.getUrl().equals(file.getUrl())) {
          return rootTreeNode;
        }

        if (!VfsUtil.isAncestor(nodeFile, file, false)) {
          return null;
        }
      } else {
        return null;
      }
    }

    for (MPSTreeNode node : rootTreeNode) {
      node.init();
      MPSTreeNode result = getNode(node, file);
      if (result != null) {
        return result;
      }
    }

    return null;
  }
 private void appendChosenAnnotationsRoot(
     @NotNull final OrderEntry entry, @NotNull final VirtualFile vFile) {
   if (entry instanceof LibraryOrderEntry) {
     Library library = ((LibraryOrderEntry) entry).getLibrary();
     LOG.assertTrue(library != null);
     final ModifiableRootModel rootModel =
         ModuleRootManager.getInstance(entry.getOwnerModule()).getModifiableModel();
     final Library.ModifiableModel model = library.getModifiableModel();
     model.addRoot(vFile, AnnotationOrderRootType.getInstance());
     model.commit();
     rootModel.commit();
   } else if (entry instanceof ModuleSourceOrderEntry) {
     final ModifiableRootModel model =
         ModuleRootManager.getInstance(entry.getOwnerModule()).getModifiableModel();
     final JavaModuleExternalPaths extension =
         model.getModuleExtension(JavaModuleExternalPaths.class);
     extension.setExternalAnnotationUrls(
         ArrayUtil.mergeArrays(extension.getExternalAnnotationsUrls(), vFile.getUrl()));
     model.commit();
   } else if (entry instanceof JdkOrderEntry) {
     final SdkModificator sdkModificator = ((JdkOrderEntry) entry).getJdk().getSdkModificator();
     sdkModificator.addRoot(vFile, AnnotationOrderRootType.getInstance());
     sdkModificator.commitChanges();
   }
   myExternalAnnotations.clear();
 }