private @Nullable Editor openEditor(VirtualFile file, int textOffset){
    if (file == null || !file.isValid()){
      return null;
    }
    OpenFileDescriptor descriptor = new OpenFileDescriptor(myProject, file, textOffset);
    return FileEditorManager.getInstance(myProject).openTextEditor(descriptor, false);
  }
private @Nullable Editor openEditor(VirtualFile file, int textOffset)