code: @Override
    public List<? extends BoundedSource<T>> split(long desiredBundleSizeBytes,
        PipelineOptions options) throws Exception {
  
      List<? extends BoundedSource<T>> splits = delegate.split(desiredBundleSizeBytes, options);
      Collections.shuffle(splits);
      return splits;
    }
docs: Shuffles the delegate source's splits.