docs: private void reset() {
          this.numChunks = 0;
          this.baseDir = null;
          this.indexFileSizes.clear();
          this.dataFileSizes.clear();
          this.fileNames.clear();
          this.indexFiles.clear();
          this.mappedIndexFileReader.clear();
  
          this.dataFiles.clear();
          this.chunkIdToChunkStart.clear();
          this.chunkIdToNumChunks.clear();
  
      }