code: public int getUncompletedCorrelationIdPosition(String id) {
          if (uncompletedCorrelationIdsNodeMap.containsKey(id)) {
              return uncompletedCorrelationIdsNodeMap.get(id).getPosition();
          }
          return -1;
      }
docs: This method returns the child position associated with the
  supplied correlation id.
  
  @param id The correlation id
  @return The child node position, or -1  if unknown