Unified or Concrete Class names - which to use and when?

Historically, after the introduction of the Symfony DependencyInjection Component (DIC), OXID eShop code “diverged” into 2 application areas:

New, “DI” namespaces (e.g. Internal)
“Non-DI”, aka “Traditional” namespaces (e.g. Core, Application).

DI Namespaces

Note

Always use concrete class names with DIC!

The Symfony DIC can manage all the “newer” namespaces (such namespaces can be identified by the presence of services.yaml file in their root directory, see source/Internal/services.yaml or similar).

Because DIC functionality “supersedes” the Inheritance Chain there, we should never use oxNew() and Unified Namespaces and stick only to the concrete class names for all classes in DI Namespaces.

Example using the concrete interface name for the injected service

public function __contruct(
    \OxidEsales\EshopCommunity\Internal\ServiceInterface $service
) {
    $this->service = $service;
}

More information:

Non-Di Namespaces

Note

Never use concrete class names with oxNew()!

In the “Traditional” code, using the concrete class names instead of the Unified Namespaces, will circumvent the creation of the Inheritance Chain and oxNew functionality. Therefore, using the “real” class names for extendable classes in Non-Di Namespaces is discouraged.

Example using the Unified Namespace for model instantiation

$myModel = oxNew(\OxidEsales\Eshop\Application\Model\MyModel::class);

More information: