我尝试用 ExecutorService 结束executorService.shutdown();，如果没有用，用executorService.shutdown();. 问题是，无法停止 executorService 并且程序仍在运行。
这是我的课程，它将启动一个 WatchService 来监视目录的更改：
public class FileWatcher {
/**
* This Class starts a WatchService to get changes on a specific folder.
*/
Path dir;
private final ConfigManager configManager;
private final FileHandler fileHandler;
private ExecutorService executorService;
public FileWatcher(ConfigManager configManager, FileHandler fileHandler) {
this.configManager = configManager;
this.fileHandler = fileHandler;
}
public void start() {
dir = configManager.getConfig().getJdfPath();
//executorService = Executors.newFixedThreadPool(1);
executorService = Executors.newSingleThreadExecutor();
Runnable runWatcher;
runWatcher = new Runnable() {
@Override
public void run() {
try {
startWatcher();
} catch (IOException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
};
executorService.execute(runWatcher);
}
private void startWatcher() throws IOException, InterruptedException {
/**
* Create a new WatchService which detects created and modified files. To
* let it detect deleted files add ENTRY_DELETE to dir.register().
*/
WatchService watcher = FileSystems.getDefault().newWatchService();
WatchKey key = dir.register(watcher, ENTRY_CREATE, ENTRY_MODIFY);
while (!Thread.currentThread().isInterrupted()) {
key = waitForEvents(watcher, key);
}
}
private WatchKey waitForEvents(WatchService watcher, WatchKey key) {
/**
* The WatchService tells the FileHandler the Filename of the changed or
* new file in the given folder.
*/
try {
key = watcher.take();
} catch (InterruptedException e) {
executorService.shutdown();
} catch (ClosedWatchServiceException e) {
executorService.shutdown();
}
for (WatchEvent<?> event : key.pollEvents()) {
fileHandler.setPath((Path) event.context());
}
key.reset();
return key;
}
public void stop() {
stopWatcher();
}
private void stopWatcher() {
executorService.shutdown(); // Disable new tasks from being submitted
try {
// Wait a while for existing tasks to terminate
if (!executorService.awaitTermination(10, TimeUnit.SECONDS)) {
executorService.shutdownNow(); // Cancel currently executing tasks
// Wait a while for tasks to respond to being cancelled
if (!executorService.awaitTermination(10, TimeUnit.SECONDS))
System.err.println("Pool did not terminate");
}
} catch (InterruptedException ie) {
// (Re-)Cancel if current thread also interrupted
executorService.shutdownNow();
// Preserve interrupt status
Thread.currentThread().interrupt();
}
}
}
我stopWatcher()从 oracle java api] 1得到了方法。我写了一个简单的类来测试 FileWatcher 类。
public class TestFileWatcher {
static Path path;
static ConfigManager configmanager;
public static void main(String[] args) {
path = Paths.get("D:/testfolder");
FileHandler filehandler = new FileHandler() {
@Override
public void setPath(Path path) {
System.out.println("file: " + path);
}
@Override
public Path getPath() {
// TODO Auto-generated method stub
return null;
}
};
final Config config;
config = new Config() {
@Override
public Path getJdfPath() {
// TODO Auto-generated method stub
return path;
}
};
configmanager = new ConfigManager() {
@Override
public void injectConfig(Config config) {
// TODO Auto-generated method stub
}
@Override
public Config getConfig() {
// TODO Auto-generated method stub
return config;
}
};
configmanager.injectConfig(config);
filehandler.setPath(path);
final FileWatcher filewatcher = new FileWatcher(configmanager, filehandler);
filewatcher.start();
Timer timer = new Timer();
boolean stopped;
TimerTask closeWatcherTask = new TimerTask(){
@Override
public void run() {
System.out.println("filewatcher stopped.");
filewatcher.stop();
}
};
long duration = 2000;
timer.schedule(closeWatcherTask, duration);
return;
}
}
因此，当我启动测试应用程序以启动 FileWatcher 并在 2 秒后结束它时，程序告诉我：Pool did not terminate. 我可以更改什么以正确终止它？
顺便说一句，ConfigManager 和 FileHandler 是接口，我在其中获得了我必须进行更改的路径。