code: public void addUncompletedCorrelationId(String id, Node node, int position) {
          NodePlaceholder placeholder = new NodePlaceholder();
          placeholder.setNode(node);
          placeholder.setPosition(position);
          uncompletedCorrelationIdsNodeMap.put(id, placeholder);
      }
docs: This method associates a parent node and child position with a
  correlation id.
  
  @param id The correlation id
  @param node The parent node
  @param position The child node position within the parent node