code: static ModelNode createOperation(final ModelNode operationToValidate) {
          PathAddress pa = PathAddress.pathAddress(operationToValidate.require(ModelDescriptionConstants.OP_ADDR));
          PathAddress realmPA = null;
          for (int i = pa.size() - 1; i > 0; i--) {
              PathElement pe = pa.getElement(i);
              if (SECURITY_REALM.equals(pe.getKey())) {
                  realmPA = pa.subAddress(0, i + 1);
                  break;
              }
          }
          assert realmPA != null : "operationToValidate did not have an address that included a " + SECURITY_REALM;
          return Util.getEmptyOperation("validate-authentication", realmPA.toModelNode());
      }
docs: Creates an operations that targets this handler.
  @param operationToValidate the operation that this handler will validate
  @return  the validation operation