private function _populateClassesPerAnnotations($class, Collection $annotations)
    {
        foreach ($annotations->getAll() as $name => $annotation) {
            $cacheKey = $name . '.classbyannotations';
            if (!isset($this->_classesAnnotated[$name])) {
                $this->_classesAnnotated[$name] = array();
            }
            $this->_classesAnnotated[$name][$class] = $class;
            $this->_cache->store($cacheKey, $this->_classesAnnotated);
        }
    }