public RdfResultObject getRdfResultObject(ResultObject oldResultObject, boolean isConjunction) {
RdfResultObject result = new RdfResultObject();
if (oldResultObject != null) {
if (!result.isFresh() && isConjunction) {
result.intersectResults(oldResultObject);
} else {
result.addResults(oldResultObject);
}
result.addHistoryInfo(oldResultObject.getHistoryInfo());