Your error (Jackson Import) and your code doesnt seem to be related (and your code uses no OSGi Features). Can you Share your repo, especially the bundle Plugin config?
I try since hours to build a Thread-Safe OSGi Service which watches a directory for file changes and executes on modification. See description bellow. Can someone give me a tip a working example for a thread safe service?
The problem is, that I get not the Thread correctly registered. I have already successfully registered some services in activator and bundle Context. But somehow I did not get this started on the DirectoryWatcher. And in different experiments and when the execution starts, then I get the following erros:
import java.io.IOException;
import java.nio.file.*;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.HashMap;
import java.util.Map;
public class RecursiveDirectoryWatcher implements Runnable {
private final Path rootDir;
private final WatchService watchService;
private final Map<WatchKey, Path> keyToPathMap;
public RecursiveDirectoryWatcher(String rootDir) throws IOException {
this.rootDir = Paths.get(rootDir);
this.watchService = FileSystems.getDefault().newWatchService();
this.keyToPathMap = new HashMap<>();
registerAll(this.rootDir); // Register all subdirectories
}
// Register a directory and all its subdirectories
private void registerAll(final Path start) throws IOException {
Files.walkFileTree(start, new SimpleFileVisitor<>() {
@Override
public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) throws IOException {
registerDirectory(dir);
return FileVisitResult.CONTINUE;
}
});
}
// Register a single directory with the WatchService
private void registerDirectory(Path dir) throws IOException {
WatchKey key = dir.register(
watchService,
StandardWatchEventKinds.ENTRY_CREATE,
StandardWatchEventKinds.ENTRY_MODIFY,
StandardWatchEventKinds.ENTRY_DELETE
);
keyToPathMap.put(key, dir);
System.out.println("Watching directory: " + dir);
}
@Override
public void run() {
System.out.println("Starting to watch directory: " + rootDir);
while (true) {
WatchKey key;
try {
key = watchService.take(); // Wait for events
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
System.out.println("Directory watching interrupted.");
break;
}
Path dir = keyToPathMap.get(key);
if (dir == null) {
System.err.println("WatchKey not recognized!");
continue;
}
for (WatchEvent<?> event : key.pollEvents()) {
WatchEvent.Kind<?> kind = event.kind();
// Resolve the relative file name to an absolute path
Path name = (Path) event.context();
Path fullPath = dir.resolve(name);
System.out.println("Event: " + kind + " on file: " + fullPath);
// EXECUTE HERE THE CODE OF AN OSGI-BUNDLE which parses JSON-Files
// If a new directory is created, register it
if (kind == StandardWatchEventKinds.ENTRY_CREATE) {
try {
if (Files.isDirectory(fullPath)) {
registerAll(fullPath);
}
} catch (IOException e) {
System.err.println("Failed to register directory: " + fullPath);
}
}
}
// Reset the key to continue watching
boolean valid = key.reset();
if (!valid) {
keyToPathMap.remove(key);
if (keyToPathMap.isEmpty()) {
System.out.println("All directories are no longer valid. Stopping.");
break;
}
}
}
}
public static void main(String[] args) {
String directoryToWatch = "/path/to/root/directory";
try {
// Create a new thread for the directory watcher
Thread watcherThread = new Thread(new RecursiveDirectoryWatcher(directoryToWatch));
watcherThread.start();
// Main thread can do other tasks while the watcher thread runs
System.out.println("Main thread is free to do other tasks...");
} catch (IOException e) {
e.printStackTrace();
}
}
}
