protected function generateImplements(\ReflectionClass $reflectionClass)
    {

        // load the class interfaces
        $interfaces = $reflectionClass->getInterfaces();

        // initialize the array for the
        $generateInterfaces = array();

        // iterate over the specified interfaces
        foreach ($interfaces as $interfaceName => $interface) {
            // clean them up to avoid doubles
            foreach ($generateInterfaces as $obj) {
                if ($obj->isSubclassOf($interface)) {
                    continue 2;
                }
            }

            // traversable interface can not be implemented directly, so ignore it
            if ($interface->getName() === 'Traversable') {
                continue;
            }

            // append the interface
            $generateInterfaces[sprintf('\\%s', $interfaceName)] = $interface;
        }

        // implode the interfaces and return them as string
        return implode(', ', array_keys($generateInterfaces));
    }