@Override
      public void accept(VirtualFile file) {
        if (file != null) {
          if (file.isDirectory()) {
            // need to traverse directories on IDE side, because JPS build
            // has less knowledge to efficiently traverse the directory up-down according to the project layout
            dirsToTraverse.add(file);
          }
          else {
            collectPaths(file, filesChanged, false);
          }
        }
      }
@Override
      public void accept(VirtualFile file)