public class WacthFileUtil {

        public static void main(String[] args) {

            //define a folder root

            Path myDir = Paths.get("test\\phone");

            while (true) {

                try {

                    WatchService watcher = myDir.getFileSystem().newWatchService();

                    myDir.register(watcher, StandardWatchEventKinds.ENTRY_CREATE, StandardWatchEventKinds.ENTRY_DELETE,

                            StandardWatchEventKinds.ENTRY_MODIFY);

                    WatchKey watckKey = watcher.take();

                    List<WatchEvent<?>> events = watckKey.pollEvents();

                    for (WatchEvent event : events) {

                        if (event.kind() == StandardWatchEventKinds.ENTRY_CREATE) {

                            System.out.println("Created: " + event.context().toString());

                        }

                        if (event.kind() == StandardWatchEventKinds.ENTRY_DELETE) {

                            System.out.println("Delete: " + event.context().toString());

                        }

                        if (event.kind() == StandardWatchEventKinds.ENTRY_MODIFY) {

                            System.out.println("Modify: " + event.context().toString());

                        }

                    }

                } catch (Exception e) {

                    System.out.println("Error: " + e.toString());

                }

            }

        }

    }