void add(ComparableAEH individualHandler) {
      if (uniqueSample == null) {
        isQualifiedSample = !candidatesConflictHandler.isDisqualified(0);
        uniqueSample = individualHandler;
        ComparableEEH parent = uniqueSample.getParentHandler();
        if (parent instanceof ValidatingEEH)
          ((ValidatingEEH) parent).setContextErrorHandlerIndex(ValidatingEEH.COMMON);
      } else {
        if (!individualHandler.functionalEquivalent(uniqueSample)) {
          state = conflict;
          reset();
        } else if (!isQualifiedSample
            && !candidatesConflictHandler.isDisqualified(individualHandlers.size())) {
          // }

          ComparableEEH sampleParent = uniqueSample.getParentHandler();
          if (sampleParent instanceof ValidatingEEH)
            ((ValidatingEEH) sampleParent).restorePreviousHandler();
          ComparableEEH parent = individualHandler.getParentHandler();
          if (parent instanceof ValidatingEEH)
            ((ValidatingEEH) parent).setContextErrorHandlerIndex(ValidatingEEH.COMMON);

          uniqueSample = individualHandler;
          isQualifiedSample = true;
        }
      }

      individualHandlers.add(individualHandler);
    }
    void reset() {
      if (uniqueSample == null) return;

      ComparableEEH sampleParent = uniqueSample.getParentHandler();
      if (sampleParent instanceof ValidatingEEH)
        ((ValidatingEEH) sampleParent).restorePreviousHandler();

      uniqueSample = null;
      isQualifiedSample = false;
    }