@Override
        protected @NotNull ListSelection<? extends Producer> loadRequestProducers() throws DiffRequestProducerException {
          try {
            return resultRef.get();
          }
          catch (InterruptedException | ExecutionException ex) {
            throw new DiffRequestProducerException(ex);
          }
        }
@Override
        protected @NotNull ListSelection<? extends Producer> loadRequestProducers()