code: public CheckpointAlgorithm<Chunk<T>> getOrCreateCheckpointAlgorithm()
     {
        Node node = childNode.getOrCreate("checkpoint-algorithm");
        CheckpointAlgorithm<Chunk<T>> checkpointAlgorithm = new CheckpointAlgorithmImpl<Chunk<T>>(this, "checkpoint-algorithm", childNode, node);
        return checkpointAlgorithm;
     }
docs: If not already created, a new <code>checkpoint-algorithm</code> element with the given value will be created.
  Otherwise, the existing <code>checkpoint-algorithm</code> element will be returned.
  @return  a new or existing instance of <code>CheckpointAlgorithm<Chunk<T>></code>