public abstract WatchService newWatchService () throws IOException

Constructs a new WatchService (optional operation).

This method constructs a new watch service that may be used to watch registered objects for changes and events.

Returns:  a new watch service

UnsupportedOperationException     If this FileSystem does not support watching file system objects for changes and events. This exception is not thrown by FileSystems created by the default provider.
IOException     If an I/O error occurs