java.nio.file.StandardWatchEventKinds Java Examples

public ExternalDatabaseLookupService(final Path location) throws IOException {
    final Path absoluteLocation = location.toAbsolutePath();
    final Path locationParent = absoluteLocation.getParent();
    if (null == locationParent) {
        throw new IllegalArgumentException("Could not determine parent directory of GeoIP2 database: " + absoluteLocation);
    }
    this.location = absoluteLocation;
    // Do this first, so that if it fails we don't need to clean up resources.
    databaseLookupService = new AtomicReference<>(new DatabaseLookupService(absoluteLocation));

    // Set things up so that we can reload the database if it changes.
    watcher = FileSystems.getDefault().newWatchService();
    logger.debug("Monitoring {} for changes affecting {}.", locationParent, location);
    locationParent.register(watcher, StandardWatchEventKinds.ENTRY_MODIFY);
    // The database will be loaded in the background.
    backgroundWatcher.execute(this::processWatchEvents);
}
 

/**
 * Instantiates a new file system watcher.
 *
 * @param parent the parent
 * @param path the path
 */
public void addWatch(FileWatcherUpdateInterface parent, Path path) {
    if (path != null) {
        // The directory that has to be watched needs to be registered. Any
        // object that implements the Watchable interface can be registered.

        // Register three events. i.e. whenever a file is created, deleted or
        // modified the watcher gets informed
        try {
            WatchKey key =
                    path.register(
                            watchService,
                            StandardWatchEventKinds.ENTRY_CREATE,
                            StandardWatchEventKinds.ENTRY_DELETE,
                            StandardWatchEventKinds.ENTRY_MODIFY);
            watcherMap.put(key, parent);
        } catch (IOException e) {
            // Do nothing
        }
    }
}
 

public void watchDirs(Set<Path> dirs) {
    if (mWatcher == null) {
        return;
    }
    Map<Path, WatchKey> keep = new HashMap<>();
    for (Path p : dirs) {
        WatchKey key = mPathKeyMap.get(p);
        if (key == null) {
            try {
                keep.put(p, p.register(mWatcher, StandardWatchEventKinds.ENTRY_CREATE, StandardWatchEventKinds.ENTRY_DELETE));
            } catch (IOException exception) {
                Log.error(exception);
            }
        } else {
            keep.put(p, key);
            mPathKeyMap.remove(p);
        }
    }
    for (WatchKey watchKey : mPathKeyMap.values()) {
        watchKey.cancel();
    }
    mPathKeyMap = keep;
}
 

@SuppressWarnings ( "unchecked" )
private void handleEvent ( final WatchEvent<?> event )
{
    final Kind<?> kind = event.kind ();

    if ( kind == StandardWatchEventKinds.OVERFLOW )
    {
        // FIXME: full rescan
        return;
    }

    final Path path = this.path.resolve ( ( (WatchEvent<Path>)event ).context () );

    if ( kind == StandardWatchEventKinds.ENTRY_CREATE )
    {
        this.listener.event ( path, Event.ADDED );
    }
    else if ( kind == StandardWatchEventKinds.ENTRY_DELETE )
    {
        this.listener.event ( path, Event.REMOVED );
    }
    else if ( kind == StandardWatchEventKinds.ENTRY_MODIFY )
    {
        this.listener.event ( path, Event.MODIFIED );
    }
}
 

@Override
public void handleFileChanged(Kind<?> operation, String fileAbsolutePathname) {
	if (StandardWatchEventKinds.ENTRY_CREATE.equals(operation)) {
		DecryptedFile recentlyRemovedEntry = recentlyRemoved.getIfPresent(fileAbsolutePathname);
		if (recentlyRemovedEntry != null) {
			addOrUpdate(recentlyRemovedEntry);
		}
		return;
	}

	if (StandardWatchEventKinds.ENTRY_DELETE.equals(operation)) {
		remove(fileAbsolutePathname);
		return;
	}

	// Other cases not supported -- not needed
}
 

private WatchEvent.Kind<?> translateActionToEvent(int action) {
    switch (action) {
        case FILE_ACTION_MODIFIED :
            return StandardWatchEventKinds.ENTRY_MODIFY;

        case FILE_ACTION_ADDED :
        case FILE_ACTION_RENAMED_NEW_NAME :
            return StandardWatchEventKinds.ENTRY_CREATE;

        case FILE_ACTION_REMOVED :
        case FILE_ACTION_RENAMED_OLD_NAME :
            return StandardWatchEventKinds.ENTRY_DELETE;

        default :
            return null;  // action not recognized
    }
}
 

private WatchEvent.Kind<?> translateActionToEvent(int action) {
    switch (action) {
        case FILE_ACTION_MODIFIED :
            return StandardWatchEventKinds.ENTRY_MODIFY;

        case FILE_ACTION_ADDED :
        case FILE_ACTION_RENAMED_NEW_NAME :
            return StandardWatchEventKinds.ENTRY_CREATE;

        case FILE_ACTION_REMOVED :
        case FILE_ACTION_RENAMED_OLD_NAME :
            return StandardWatchEventKinds.ENTRY_DELETE;

        default :
            return null;  // action not recognized
    }
}
 

private WatchEvent.Kind<?> translateActionToEvent(int action) {
    switch (action) {
        case FILE_ACTION_MODIFIED :
            return StandardWatchEventKinds.ENTRY_MODIFY;

        case FILE_ACTION_ADDED :
        case FILE_ACTION_RENAMED_NEW_NAME :
            return StandardWatchEventKinds.ENTRY_CREATE;

        case FILE_ACTION_REMOVED :
        case FILE_ACTION_RENAMED_OLD_NAME :
            return StandardWatchEventKinds.ENTRY_DELETE;

        default :
            return null;  // action not recognized
    }
}
 

@Override
public FileVisitResult preVisitDirectory(Path path, BasicFileAttributes attrs)
    throws IOException {
  // It's important that we register the directory before we visit its children. This way we
  // are guaranteed to see new files/directories either on this #getDiff or the next one.
  // Otherwise, e.g., an intra-build creation of a child directory will be forever missed if it
  // happens before the directory is listed as part of the visitation.
  Preconditions.checkState(path.isAbsolute(), path);
  // On windows we register the root path with ExtendedWatchEventModifier.FILE_TREE
  // Therefore there is no need to register recursive watchers
  if (!isWindows) {
    WatchKey key =
        path.register(
            watchService,
            StandardWatchEventKinds.ENTRY_CREATE,
            StandardWatchEventKinds.ENTRY_MODIFY,
            StandardWatchEventKinds.ENTRY_DELETE);
    watchKeyToDirBiMap.put(key, path);
  }
  visitedAbsolutePaths.add(path);
  return FileVisitResult.CONTINUE;
}
 

public void monitor(Path directory, Path sourceFile, Runnable action) {
    if (watchService != null) {
        logger(PathsWatcher.class).info("registering action %d for monitoring %s in %s", System.identityHashCode(action), sourceFile, directory);
        Map<String, List<Runnable>> fileAction = filesActions.computeIfAbsent(
                directory.toString(), (p) -> {
                    try {
                        directory.register(watchService, new WatchEvent.Kind[]{ StandardWatchEventKinds.ENTRY_MODIFY, StandardWatchEventKinds.ENTRY_CREATE, StandardWatchEventKinds.ENTRY_DELETE}, SensitivityWatchEventModifier.HIGH);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                    return new HashMap<>();
                });

        List<Runnable> actions = fileAction.computeIfAbsent(sourceFile.toString(), k -> new LinkedList<>());
        actions.add(action);
        logger(PathsWatcher.class).debug("%d CSS modification actions registered for file %s", actions.size(), sourceFile);
    } else {
        logger(PathsWatcher.class).warn("no WatchService active, CSS monitoring cannot occur");
    }
}
 

private WatchEvent.Kind<?> translateActionToEvent(int action) {
    switch (action) {
        case FILE_ACTION_MODIFIED :
            return StandardWatchEventKinds.ENTRY_MODIFY;

        case FILE_ACTION_ADDED :
        case FILE_ACTION_RENAMED_NEW_NAME :
            return StandardWatchEventKinds.ENTRY_CREATE;

        case FILE_ACTION_REMOVED :
        case FILE_ACTION_RENAMED_OLD_NAME :
            return StandardWatchEventKinds.ENTRY_DELETE;

        default :
            return null;  // action not recognized
    }
}
 

private FileWatcher(Map<Path, Consumer<Path>> registeredPaths) {
  this.registeredPaths = ImmutableMap.copyOf(registeredPaths);
  try {
    watchService = FileSystems.getDefault().newWatchService();
    ImmutableMap.Builder<WatchKey, Path> watchedDirsBuilder = ImmutableMap.builder();
    for (Map.Entry<Path, Consumer<Path>> entry : registeredPaths.entrySet()) {
      Path dir = entry.getKey().getParent();
      WatchKey key =
          dir.register(
              watchService,
              StandardWatchEventKinds.ENTRY_CREATE,
              StandardWatchEventKinds.ENTRY_DELETE,
              StandardWatchEventKinds.ENTRY_MODIFY);
      watchedDirsBuilder.put(key, dir);
    }
    this.watchedDirs = watchedDirsBuilder.build();
  } catch (IOException e) {
    throw new UncheckedIOException("Could not create WatchService.", e);
  }
  executor = Executors.newSingleThreadScheduledExecutor();
}
 

/**
 * Returns true if and only if the path corresponding to a WatchEvent
 * represents the given file. This will be the case for Create, Modify,
 * Delete events.
 * 
 * @param file
 *            the file to restrict events to
 * @return predicate
 */
private final static Func1<WatchEvent<?>, Boolean> onlyRelatedTo(final File file) {
    return new Func1<WatchEvent<?>, Boolean>() {

        @Override
        public Boolean call(WatchEvent<?> event) {

            final boolean ok;
            if (file.isDirectory())
                ok = true;
            else if (StandardWatchEventKinds.OVERFLOW.equals(event.kind()))
                ok = true;
            else {
                Object context = event.context();
                if (context != null && context instanceof Path) {
                    Path p = (Path) context;
                    Path basePath = getBasePath(file);
                    File pFile = new File(basePath.toFile(), p.toString());
                    ok = pFile.getAbsolutePath().equals(file.getAbsolutePath());
                } else
                    ok = false;
            }
            return ok;
        }
    };
}
 

public PluginEngine(final PluginListener pluginListener) throws IOException {
	if (pluginListener == null) {
		throw new IllegalArgumentException("pluginListener cannot be null");
	}

	pluginDir = Paths.get(System.getProperty("shootoff.plugins"));
	this.pluginListener = pluginListener;

	if (!Files.exists(pluginDir) && !pluginDir.toFile().mkdirs()) {
		logger.error("The path specified by shootoff.plugins doesn't exist and we couldn't create it.");
		return;
	}

	if (!Files.isDirectory(pluginDir)) {
		logger.error("Can't enumerate existing plugins or watch for new plugins because the "
				+ "shootoff.plugins property is not set to a directory");
	}

	registerDefaultStandardTrainingExercises();
	enumerateExistingPlugins();
	registerDefaultProjectorExercises();

	pluginDir.register(watcher, StandardWatchEventKinds.ENTRY_CREATE, StandardWatchEventKinds.ENTRY_DELETE);
}
 

public MacOSXWatchKey(
    AbstractWatchService macOSXWatchService,
    Iterable<? extends WatchEvent.Kind<?>> events,
    int queueSize) {
  super(macOSXWatchService, null, events, queueSize);
  boolean reportCreateEvents = false;
  boolean reportModifyEvents = false;
  boolean reportDeleteEvents = false;

  for (WatchEvent.Kind<?> event : events) {
    if (event == StandardWatchEventKinds.ENTRY_CREATE) {
      reportCreateEvents = true;
    } else if (event == StandardWatchEventKinds.ENTRY_MODIFY) {
      reportModifyEvents = true;
    } else if (event == StandardWatchEventKinds.ENTRY_DELETE) {
      reportDeleteEvents = true;
    }
  }
  this.reportCreateEvents = reportCreateEvents;
  this.reportDeleteEvents = reportDeleteEvents;
  this.reportModifyEvents = reportModifyEvents;
}
 

public static void main(String[] args) throws IOException, InterruptedException {
	Path tmpDir = Paths.get("tmp");
	WatchService watchService = FileSystems.getDefault().newWatchService();
	Path monitoredFolder = tmpDir;
	monitoredFolder.register(watchService, StandardWatchEventKinds.ENTRY_CREATE, StandardWatchEventKinds.ENTRY_DELETE);
	
	tmpDir.toFile().mkdirs();
	new FileChanger(tmpDir).start();
	while (true) {
		System.out.println("Waiting for event");
		WatchKey watchKey = watchService.take();
		for (WatchEvent<?> event : watchKey.pollEvents()) {
			System.out.println("Detected event " + event.kind().name() + " on file " + event.context().toString());
		}
		watchKey.reset();
	}
}
 

/**
 * Register the given directory with the WatchService
 *
 * @param aDir
 *        Directory to be watched. May not be <code>null</code>.
 */
private void _registerDir (@Nonnull final Path aDir) throws IOException
{
  if (LOGGER.isDebugEnabled ())
    LOGGER.debug ("Register directory " +
                  aDir +
                  (m_bRecursive && !m_bRegisterRecursiveManually ? " (recursively)" : ""));

  final WatchEvent.Kind <?> [] aKinds = new WatchEvent.Kind <?> [] { StandardWatchEventKinds.ENTRY_CREATE,
                                                                     StandardWatchEventKinds.ENTRY_DELETE,
                                                                     StandardWatchEventKinds.ENTRY_MODIFY };

  // throws exception when using with modifiers even if null
  final WatchKey aKey = m_aModifiers != null ? aDir.register (m_aWatcher, aKinds, m_aModifiers)
                                             : aDir.register (m_aWatcher, aKinds);
  m_aKeys.put (aKey, aDir);
}
 

/**
 * Create a WatchService to watch for changes in the given directory
 * and then attempt to close the WatchService and change a registration
 * at the same time.
 */
static void test(Path dir, ExecutorService pool) throws Exception {
    WatchService watcher = FileSystems.getDefault().newWatchService();

    // initial registration
    dir.register(watcher, StandardWatchEventKinds.ENTRY_CREATE);

    // submit tasks to close the WatchService and update the registration
    Future<Void> closeResult;
    Future<Boolean> registerResult;

    if (RAND.nextBoolean()) {
        closeResult = pool.submit(newCloserTask(watcher));
        registerResult = pool.submit(newRegisterTask(watcher, dir));
    } else {
        registerResult = pool.submit(newRegisterTask(watcher, dir));
        closeResult = pool.submit(newCloserTask(watcher));
    }

    closeResult.get();
    registerResult.get();

}
 

public StorageWatcher ( final StorageManager storageManager, final BaseWatcher baseWatcher, final Path path, final WatchService watcher ) throws IOException
{
    this.storageManager = storageManager;
    this.baseWatcher = baseWatcher;
    this.watcher = watcher;
    this.path = path;

    this.key = path.register ( watcher, StandardWatchEventKinds.ENTRY_CREATE, StandardWatchEventKinds.ENTRY_DELETE, StandardWatchEventKinds.ENTRY_MODIFY );
    baseWatcher.addWatcherMap ( path, this );

    final File nativeDir = new File ( path.toFile (), "native" );
    baseWatcher.addWatcherMap ( nativeDir.toPath (), this );

    logger.debug ( "Checking native dir: {}", nativeDir );

    if ( nativeDir.exists () && nativeDir.isDirectory () )
    {
        this.nativeKey = nativeDir.toPath ().register ( this.watcher, StandardWatchEventKinds.ENTRY_CREATE, StandardWatchEventKinds.ENTRY_MODIFY, StandardWatchEventKinds.ENTRY_DELETE );
        check ();
    }
}
 

private void watchNewSourceOrLibraryPath(Path sourceOrLibraryPath, WorkspaceFolderData folderData)
{
    try
    {
        java.nio.file.Files.walkFileTree(sourceOrLibraryPath, new SimpleFileVisitor<Path>()
        {
            @Override
            public FileVisitResult preVisitDirectory(Path subPath, BasicFileAttributes attrs) throws IOException
            {
                WatchKey watchKey = subPath.register(sourcePathWatcher, StandardWatchEventKinds.ENTRY_CREATE, StandardWatchEventKinds.ENTRY_DELETE, StandardWatchEventKinds.ENTRY_MODIFY);
                folderData.sourceOrLibraryPathWatchKeys.put(watchKey, subPath);
                return FileVisitResult.CONTINUE;
            }
        });
    }
    catch (IOException e)
    {
        System.err.println("Failed to watch source or library path: " + sourceOrLibraryPath.toString());
        e.printStackTrace(System.err);
    }
}
 

public BaseWatcher ( final StorageManager storageManager, final File base ) throws IOException
{
    this.storageManager = storageManager;
    this.base = base.toPath ();
    this.watcher = FileSystems.getDefault ().newWatchService ();

    this.baseKey = base.toPath ().register ( this.watcher, StandardWatchEventKinds.ENTRY_CREATE, StandardWatchEventKinds.ENTRY_DELETE );

    logger.debug ( "Checking for initial storages" );

    for ( final File child : this.base.toFile ().listFiles () )
    {
        logger.debug ( "Found initial storage dir - {}", child );
        checkAddStorage ( child.toPath () );
    }

    startWatcher ();
}
 

public void addCollectionFileChangeListener(CollectionFileChangeListener listener) {
  if (null == listeners) {
    listeners = new ArrayList<CollectionFileChangeListener>();

    listeners.add(listener);

    collectionFilesWatcherExecutor = Executors.newSingleThreadExecutor(
        new ThreadFactoryBuilder().setNameFormat("jsondb-files-watcher-thread-%d").build());

    try {
      watcher = dbConfig.getDbFilesPath().getFileSystem().newWatchService();
      dbConfig.getDbFilesPath().register(watcher, StandardWatchEventKinds.ENTRY_CREATE,
                                                  StandardWatchEventKinds.ENTRY_DELETE,
                                                  StandardWatchEventKinds.ENTRY_MODIFY);
    } catch (IOException e) {
      logger.error("Failed to create the WatchService for the dbFiles location", e);
      throw new JsonDBException("Failed to create the WatchService for the dbFiles location", e);
    }

    collectionFilesWatcherExecutor.execute(new CollectionFilesWatcherRunnable());
  } else {
    listeners.add(listener);
  }
}
 

private WatchEvent.Kind<?> translateActionToEvent(int action) {
    switch (action) {
        case FILE_ACTION_MODIFIED :
            return StandardWatchEventKinds.ENTRY_MODIFY;

        case FILE_ACTION_ADDED :
        case FILE_ACTION_RENAMED_NEW_NAME :
            return StandardWatchEventKinds.ENTRY_CREATE;

        case FILE_ACTION_REMOVED :
        case FILE_ACTION_RENAMED_OLD_NAME :
            return StandardWatchEventKinds.ENTRY_DELETE;

        default :
            return null;  // action not recognized
    }
}
 

@Override
public void run() {
    while (true) {
        try {
            WatchKey key = watchService.take();

            if (key == trustedKey) {
                for (WatchEvent<?> watchEvent : key.pollEvents()) {
                    WatchEvent.Kind<?> kind = watchEvent.kind();

                    if (kind != StandardWatchEventKinds.OVERFLOW) {
                        synchronizeTrustedCertificates();
                    }
                }
            }

            if (!key.reset()) {
                break;
            }
        } catch (InterruptedException e) {
            logger.error("Watcher interrupted.", e);
        }
    }
}
 

public static void main(String[] args) {
    DirectoryWatcher dictionaryWatcher = new DirectoryWatcher(new WatcherCallback(){
        private long lastExecute = System.currentTimeMillis();
        @Override
        public void execute(WatchEvent.Kind<?> kind, String path) {
            if(System.currentTimeMillis() - lastExecute > 1000){                  
                lastExecute = System.currentTimeMillis();
                //刷新词典
                System.out.println("事件："+kind.name()+" ,路径："+path);
            }
        }
    }, StandardWatchEventKinds.ENTRY_CREATE,
                StandardWatchEventKinds.ENTRY_MODIFY,
                StandardWatchEventKinds.ENTRY_DELETE);
    //监控DIC目录及其所有子目录的子目录...递归
    dictionaryWatcher.watchDirectoryTree("d:/DIC");
    //只监控DIC2目录
    dictionaryWatcher.watchDirectory("d:/DIC2");
}
 

public MacOSXWatchKey(final Watchable file, final FSEventWatchService service, final WatchEvent.Kind<?>[] events) {
    super(service);
    this.file = file;

    boolean reportCreateEvents = false;
    boolean reportModifyEvents = false;
    boolean reportDeleteEvents = false;

    for(WatchEvent.Kind<?> event : events) {
        if(event == StandardWatchEventKinds.ENTRY_CREATE) {
            reportCreateEvents = true;
        }
        else if(event == StandardWatchEventKinds.ENTRY_MODIFY) {
            reportModifyEvents = true;
        }
        else if(event == StandardWatchEventKinds.ENTRY_DELETE) {
            reportDeleteEvents = true;
        }
    }
    this.reportCreateEvents = reportCreateEvents;
    this.reportDeleteEvents = reportDeleteEvents;
    this.reportModifyEvents = reportModifyEvents;
}
 

private WatchEvent.Kind<?> translateActionToEvent(int action) {
    switch (action) {
        case FILE_ACTION_MODIFIED :
            return StandardWatchEventKinds.ENTRY_MODIFY;

        case FILE_ACTION_ADDED :
        case FILE_ACTION_RENAMED_NEW_NAME :
            return StandardWatchEventKinds.ENTRY_CREATE;

        case FILE_ACTION_REMOVED :
        case FILE_ACTION_RENAMED_OLD_NAME :
            return StandardWatchEventKinds.ENTRY_DELETE;

        default :
            return null;  // action not recognized
    }
}
 

public MacOSXWatchKey(Path path, AbstractWatchService macOSXWatchService, WatchEvent.Kind<?>[] events) {
    super(macOSXWatchService);
    this.path = path;
    boolean reportCreateEvents = false;
    boolean reportModifyEvents = false;
    boolean reportDeleteEvents = false;

    for (WatchEvent.Kind<?> event : events) {
        if (event == StandardWatchEventKinds.ENTRY_CREATE) {
            reportCreateEvents = true;
        } else if (event == StandardWatchEventKinds.ENTRY_MODIFY) {
            reportModifyEvents = true;
        } else if (event == StandardWatchEventKinds.ENTRY_DELETE) {
            reportDeleteEvents = true;
        }
    }
    this.reportCreateEvents = reportCreateEvents;
    this.reportDeleteEvents = reportDeleteEvents;
    this.reportModifyEvents = reportModifyEvents;
}
 

private void createWatchService() {
    try {
        WatchService watchService = FileSystems.getDefault().newWatchService();

        WatchKey trustedKey = trustedDir.toPath().register(
                watchService,
                StandardWatchEventKinds.ENTRY_CREATE,
                StandardWatchEventKinds.ENTRY_DELETE,
                StandardWatchEventKinds.ENTRY_MODIFY
        );

        Thread thread = new Thread(new Watcher(watchService, trustedKey));
        thread.setName("ua-certificate-directory-watcher");
        thread.setDaemon(true);
        thread.start();
    } catch (IOException e) {
        logger.error("Error creating WatchService.", e);
    }
}
 

public void watch() throws InterruptedException, IOException {
    try {
        final Path directoryPath = file.toPath().getParent();
        final WatchService watchService = FileSystems.getDefault().newWatchService();
        directoryPath.register(watchService, StandardWatchEventKinds.ENTRY_MODIFY);
        while (true) {
            final WatchKey wk = watchService.take();
            for (WatchEvent<?> event : wk.pollEvents()) {
                final Path fileChangedPath = (Path) event.context();
                if (fileChangedPath.endsWith(file.getName())) {
                    onModified();
                }
            }
            wk.reset();
        }
    } catch (Exception e) {
        logger.error("exception when handling change of mock file: {}", e.getMessage());
    }
}