如何将下面的Watcher转换为不断运行?我希望它在检测到更改后继续侦听文件。也许一个主题?
import java.io.IOException;
import java.nio.file.*;
import java.util.List;
public class Listener {
public static void main(String[] args) {
Path myDir = Paths.get("C:/file_dir/listen_to_this");
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 (IOException | InterruptedException e) {
System.out.println("Error: " + e.toString());
}
}
}
答案 0 :(得分:2)
不再需要任何线程。您可以简单地将其放在while
循环中:
public static void main(String[] args) throws Exception {
Path myDir = Paths.get("C:/file_dir/listen_to_this");
WatchService watcher = myDir.getFileSystem().newWatchService();
myDir.register(watcher, StandardWatchEventKinds.ENTRY_CREATE, StandardWatchEventKinds.ENTRY_DELETE, StandardWatchEventKinds.ENTRY_MODIFY);
while (true) {
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());
}
}
watchKey.reset();
}
}