Method: Returns the currently registered loaders indexed by their corresponding vendor directories.

Method: Turns off searching the prefix and fallback directories for classes that have not been registered with the class map.

Method: Should class lookup fail if not found in the current class map?

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.