code: public static boolean validateGrouping(HELM2Notation helm2notation) {
  		List<GroupingNotation> listGroupings = helm2notation.getListOfGroupings();
  		List<String> listPolymerIDs = helm2notation.getPolymerAndGroupingIDs();
  
  		/* validate each group */
  		for (GroupingNotation grouping : listGroupings) {
  			/* check for each group element if the polymer id is there */
  			for (GroupingElement groupingElement : grouping.getAmbiguity().getListOfElements()) {
  				if (!(listPolymerIDs.contains(groupingElement.getID().getId()))) {
  					LOG.info("Element of Group: " + groupingElement.getID().getId() + " does not exist");
  					return false;
  				}
  			}
  		}
  		return true;
  	}
docs: method to validate every GroupNotation of the Notation objects
  
  @param helm2notation
  HELM2Notation object
  @return true if the grouping is valid, false otherwise