Package host.anzo.core.service

Class FileWatcherService

java.lang.Object

host.anzo.core.service.FileWatcherService

All Implemented Interfaces:

host.anzo.commons.interfaces.startup.IShutdownable

public class FileWatcherService
extends Object
implements host.anzo.commons.interfaces.startup.IShutdownable

A singleton service for monitoring file system changes in registered directories. Supports recursive directory monitoring with file extension filtering and asynchronous event notifications.

Example usage:

 // Register a listener for JSON files in a directory
 FileWatchListener listener = new FileWatchListener() {
      void onFileChanged(FileWatchEvent event) {
          void onFileChanged(FileWatchEvent event) {
          }
      }
 }

 FileWatcherService.getInstance().registerDirectory(
     Paths.get("/path/to/dir"),
     listener,
     ".json"
 );

 // Unregister listener
 FileWatcherService.getInstance().unregisterListener(listener);

 // Shutdown the service when no longer needed
 FileWatcherService.getInstance().shutdown();
 
 

Since:

05.04.2025

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	FileWatcherService.FileWatchEvent	Represents a file system change event.
static interface	FileWatcherService.FileWatchListener	A listener interface for receiving file system change events.

Method Summary

Modifier and Type	Method	Description
void	onShutdown()	Initiates an orderly shutdown of the file watcher service.
void	registerDirectory(Path directory, FileWatcherService.FileWatchListener listener, String... extensions)	Registers a directory for monitoring with optional file extension filtering.
void	registerDirectory(Path directory, FileWatcherService.FileWatchListener listener, List<String> extensions)	Registers a directory for monitoring with extension filtering.
void	unregisterListener(FileWatcherService.FileWatchListener listener)	Unregisters all directories associated with the specified listener.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

registerDirectory

public void registerDirectory(Path directory,
 FileWatcherService.FileWatchListener listener,
 String... extensions)

Registers a directory for monitoring with optional file extension filtering. Recursively registers all subdirectories found at the time of registration.

Parameters:

directory - The directory path to monitor

listener - The listener to receive file change events

extensions - Varargs of file extensions to filter (e.g., "txt", "log")

registerDirectory

public void registerDirectory(Path directory,
 FileWatcherService.FileWatchListener listener,
 List<String> extensions)

Registers a directory for monitoring with extension filtering. This overload accepts a list of extensions instead of varargs.

Parameters:

directory - The directory path to monitor

listener - The listener to receive file change events

extensions - List of file extensions to filter

unregisterListener

public void unregisterListener(FileWatcherService.FileWatchListener listener)

Unregisters all directories associated with the specified listener. Stops receiving events for all directories monitored by this listener.

Parameters:

listener - The listener to unregister

onShutdown

public void onShutdown()

Initiates an orderly shutdown of the file watcher service.

Specified by:

onShutdown in interface host.anzo.commons.interfaces.startup.IShutdownable