core-bundle/src/Resources/contao/library/Contao/ClassLoader.php
public static function addClasses($classes)
	{
		@trigger_error('Using ClassLoader::addClasses() has been deprecated and will no longer work in Contao 5.0.', E_USER_DEPRECATED);

		foreach ($classes as $class=>$file)
		{
			self::addClass($class, $file);
		}
	}
public static function addClasses($classes)
	{
		@trigger_error('Using ClassLoader::addClasses() has been deprecated and will no longer work in Contao 5.0.', E_USER_DEPRECATED);

		foreach ($classes as $class=>$file)
		{
			self::addClass($class, $file);
		}
	}
Add multiple new classes with their file paths

@param array $classes An array of classes

@deprecated Deprecated since Contao 4.2, to be removed in Contao 5.