class KiePMMLFieldOperatorValue {

    protected String buildConstraintsString() {
        String operatorString = operator != null ? operator.getCustomOperator() : "";
        return kiePMMLOperatorValues.stream().map(KiePMMLOperatorValue::getConstraintsAsString).collect(Collectors.joining(" " + operatorString + " "));
    }

    public  KiePMMLFieldOperatorValue(final String name, final BOOLEAN_OPERATOR operator, final List<KiePMMLOperatorValue> kiePMMLOperatorValues, final List<KiePMMLFieldOperatorValue> nestedKiePMMLFieldOperatorValues);

}