// files/TreeWatcher.java

// (c)2016 MindView LLC: see Copyright.txt

// We make no guarantees that this code is fit for any purpose.

// Visit http://mindviewinc.com/Books/OnJava/ for more book information.

import java.io.IOException;

import java.nio.file.*;

import static java.nio.file.StandardWatchEventKinds.*;

import java.util.concurrent.*;

public class TreeWatcher {

static void watchDir(Path dir) {

try {

WatchService watcher =

FileSystems.getDefault().newWatchService();

dir.register(watcher, ENTRY_DELETE);

Executors.newSingleThreadExecutor().submit(() -> {

try {

WatchKey key = watcher.take();

for(WatchEvent evt : key.pollEvents()) {

System.out.println(

"evt.context(): " + evt.context() +

"\nevt.count(): " + evt.count() +

"\nevt.kind(): " + evt.kind());

System.exit(0);

}

} catch(InterruptedException e) {

return;

}

});

} catch(IOException e) {

throw new RuntimeException(e);

}

}

public static void

main(String[] args) throws Exception {

Directories.refreshTestDir();

Directories.populateTestDir();

Files.walk(Paths.get("test"))

.filter(Files::isDirectory)

.forEach(TreeWatcher::watchDir);

PathWatcher.delTxtFiles();

}

}

/* Output:

deleting test\bag\foo\bar\baz\File.txt

deleting test\bar\baz\bag\foo\File.txt

evt.context(): File.txt

evt.count(): 1

evt.kind(): ENTRY_DELETE

evt.context(): File.txt

evt.count(): 1

evt.kind(): ENTRY_DELETE

*/