Method: Returns the currently registered loaders indexed by their corresponding vendor directories.
Method: APCu prefix to use to cache found/not-found classes, if the extension is enabled.
Method: The APCu prefix in use, or null if APCu caching is not enabled.
Method: Registers this instance as an autoloader.
Method: Unregisters this instance as an autoloader.
Method: Loads the given class or interface.
Method: Finds the path to the file where the class is defined.