join table strategy ?

gistfile1.txt

Join Table scenario Proposal
----------------------------
We have two table named *Album* and *Track* that joined at some function at *Album* table model or *Track* table model.
We can't make a standarditation of where join should comes, because the answer is 'depend' of the case.
so, we need a better scenario that unique, simple, and standardize at this project.
    
1. create an Album class model

    class Album
    {
        public $id;
        public $artist;
        public $title;
    }

2. create a Track class model
    
    class Track
    {
        public $id;
        public $title;
        public $album_id;
    }

wow, we have same columns!!! we need to make a function to get other(s) :
    
    class Album
        implements ServiceLocatorAwareInterface
    {
        public $id;
        public $artist;
        public $title;
        
        public function getTrackById($id)
        {
            $track = $this->getServiceLocator()
                 ->get('My\Model\TrackTable')
                 ->getTableGateway()
                 ->select(array('album_id' => $id));
            return $track;
        }
        
        public function setServiceLocator(){ /*...*/}
        public function getServiceLocator(){/* ... */}
    }

so we can do this when echo-ing join :

    foreach($album->getTrackById($album->id) as $row)
    {
        echo $row->id; //this is a track id
    }
    
OR if we just need a current track id, we can do

    $album->getTrackById($album->id)->current()->id;
    

The problem with it is both *Album* and *Track* model is not registered at serviceManager which can inject ServiceLocatorAwareInterface, for auto invokabling it,
we need to make an 'interface' that can be utilized to 'initialized' the service, for example :

    interface TableModelInterface
    {
    
    }
 
just it!, and we apply to Album/Track class :

    class Album implements ServiceLocatorAwareInterface, TableModelInterface { ... }    

and we can create abstract_factories that auto registering service when not registered :

    class CommonModelAbstractFactory implements AbstractFactoryInterface
    {
        public function canCreateServiceWithName(ServiceLocatorInterface $locator, $name, $requestedName)
        {
            return (bool) (class_exists($requestedName) && $requestedName instanceof \TableModelInterface);
        }
    
        public function createServiceWithName(ServiceLocatorInterface $locator, $name, $requestedName)
        {
            $class = $requestedName;
            return new $class;
        }
    }
 
how ?