@Nullable
 private IProperty getSelectedProperty() {
   final Collection<DefaultMutableTreeNode> selectedNode = getSelectedNodes();
   if (selectedNode.isEmpty()) {
     return null;
   }
   final ResourceBundleEditorViewElement element =
       getSelectedElement(ContainerUtil.getFirstItem(selectedNode));
   return element instanceof ResourceBundlePropertyStructureViewElement
       ? ((ResourceBundlePropertyStructureViewElement) element).getProperty()
       : null;
 }
 public static boolean areTooManyDocumentsInTheQueue(Collection<Document> documents) {
   if (documents.size() > 100) return true;
   int totalSize = 0;
   for (Document document : documents) {
     totalSize += document.getTextLength();
     if (totalSize > 10 * FileUtilRt.MEGABYTE) return true;
   }
   return false;
 }
 @Nullable
 public ResourceBundleEditorViewElement getSelectedElementIfOnlyOne() {
   final Collection<ResourceBundleEditorViewElement> selectedElements = getSelectedElements();
   return selectedElements.size() == 1 ? ContainerUtil.getFirstItem(selectedElements) : null;
 }