public function getEndAttemptIdentifiers() {
        $endAttemptIdentifiers = new IdentifierCollection();
        
        foreach ($this->getComponentsByClassName('endAttemptInteraction') as $endAttemptInteraction) {
            $endAttemptIdentifiers[] = $endAttemptInteraction->getResponseIdentifier();
        }
        
        return $endAttemptIdentifiers;
    }