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

Exceptions:
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