private function processMetadataDrivers()
	{
		$builder = $this->getContainerBuilder();

		// At the moment, only Docblock annotations are supported, XML and YAML are not.		
		$annotationReader = $builder->addDefinition($this->prefix('metadata.annotationReader'))
			->setClass(AnnotationReader::class);

		$cachedReader = $builder->addDefinition($this->prefix('metadata.cachedReader'))
			->setClass(CachedReader::class)
			->setFactory(CachedReader::class, [
				'@' . $this->prefix('metadata.annotationReader'),
				'@' . $this->prefix('cache.annotations'),
				$this->debugMode
			]);

		$driverChain = $builder->addDefinition($this->prefix('metadata.driver'))
			->setClass(MappingDriverChain::class);

		foreach ($this->config['metadata'] as $namespace => $directory) {
			$driver = $builder->addDefinition($this->prefix('driver.' . $this->createServiceName($namespace)))
				->setClass(MappingDriver::class)
				->setFactory(AnnotationDriver::class, [
					'@' . $this->prefix('metadata.cachedReader'),
					$directory
				]);
			$driverChain->addSetup('$service->addDriver(?, ?)', [
				'@' . $this->prefix('driver.' . $this->createServiceName($namespace)), $namespace
			]);
		}
	}