public void assignConceptForUpdate(Concept concept) {
   log.debug(":: assigning concept for update =" + concept);
   conceptsForUpdate.add(
       template.getNode(concept.getNodeId()),
       NamespaceConstants.DATE_UPDATED,
       new ValueContext(concept.getDateUpdated()).indexNumeric());
 }
 public void assignConceptForEnrichment(Concept concept) {
   synchronized (lock) {
     conceptsForEnrich.add(
         template.getNode(concept.getNodeId()),
         NamespaceConstants.DATE_ENRICHED,
         new ValueContext(concept.getDateEnriched()).indexNumeric());
   }
 }