public function validateImplementation()
	{
		$required = [
			'model'         => ' does not implement a model definition.',
			'resource_path' => ' does not implement a resource path definition.',
		];

		foreach ($required as $implementation => $message) {
			if (! isset($this->{$implementation})) {
				throw new \InvalidArgumentException(static::class . $message);
			}
		}
	}