protected function evaluateXPO()
    {
        
        common_Logger::d('XPO TYPE', array('Generis Term evaluateXPO'));
		$classTerm = new core_kernel_classes_Class(RulesRdf::CLASS_URI_TERM_X_PREDICATE_OBJECT);
		$obj = $this->getUniquePropertyValue(new core_kernel_classes_Property(RulesRdf::PROPERTY_TERM_XPO_OBJECT));
		$pred = $this->getUniquePropertyValue(new core_kernel_classes_Property(RulesRdf::PROPERTY_TERM_XPO_PREDICATE));
		if($obj instanceof core_kernel_classes_Literal) {
			$objValue = $obj->literal;
		}
   		if($obj instanceof core_kernel_classes_Resource) {
			$objValue = $pred->getUri();
		}
		
		$returnValue = new core_kernel_classes_ContainerCollection(new common_Object(__METHOD__));
		$terms = $classTerm->searchInstances(array($pred->getUri() => $objValue), array('like' => false));
		foreach($terms as $term){
			$returnValue->add($term);
		}
    	return $returnValue;
        
    }