public static function fromResource(core_kernel_classes_Resource $resource) {
	    $values = $resource->getPropertiesValues(array(
			WfEngineOntology::PROPERTY_CALL_OF_SERVICES_SERVICE_DEFINITION,
			WfEngineOntology::PROPERTY_CALL_OF_SERVICES_ACTUAL_PARAMETER_IN,
			WfEngineOntology::PROPERTY_CALL_OF_SERVICES_ACTUAL_PARAMETER_OUT
	    ));
	    $serviceDefUri = current($values[WfEngineOntology::PROPERTY_CALL_OF_SERVICES_SERVICE_DEFINITION]);
	    $serviceCall = new self($serviceDefUri);
	    foreach ($values[WfEngineOntology::PROPERTY_CALL_OF_SERVICES_ACTUAL_PARAMETER_IN] as $inRes) {
	        $param = tao_models_classes_service_Parameter::fromResource($inRes);
	        $serviceCall->addInParameter($param);
	    }
	    if (!empty($values[WfEngineOntology::PROPERTY_CALL_OF_SERVICES_ACTUAL_PARAMETER_OUT])) {
	        $param = tao_models_classes_service_Parameter::fromResource(current($values[WfEngineOntology::PROPERTY_CALL_OF_SERVICES_ACTUAL_PARAMETER_OUT]));
	        $serviceCall->setOutParameter($param);
	    }
	    return $serviceCall;
	}