public function register( $entityClass, $repositoryClass )
    {

        $entityName = \Bond\get_unqualified_class($entityClass);

        if( isset($this->names[$entityName]) ) {
            throw new EntityAlreadyRegisteredException( $entityClass, $repositoryClass, $this );
        }

        $this->names[$entityName] = $entityClass;
        $this->registrations[$entityClass] = $repositoryClass;

    }