interface CommandSubscriber
{
    /**
     * @return array<class-string, string>
     */
    public static function getSubscribedCommands(): array;
}

class Locator
{
    /**
     * @var array[]
     */
    private $command_handler_ids = [];

    public function registerSubscriberService(string $service_name, string $class_name): void
    {
        if (is_a($class_name, CommandSubscriber::class, true)) {
            foreach (forward_static_call([$class_name, 'getSubscribedCommands']) as $command_name => $method) {
                $this->command_handler_ids[$command_name] = [$service_name, $method];
            }
        }
    }
}