code: public ResultSubpartitionView createSubpartitionView(int index, BufferAvailabilityListener availabilityListener) throws IOException {
  		int refCnt = pendingReferences.get();
  
  		checkState(refCnt != -1, "Partition released.");
  		checkState(refCnt > 0, "Partition not pinned.");
  
  		checkElementIndex(index, subpartitions.length, "Subpartition not found.");
  
  		ResultSubpartitionView readView = subpartitions[index].createReadView(availabilityListener);
  
  		LOG.debug("Created {}", readView);
  
  		return readView;
  	}
docs: Returns the requested subpartition.