Executor and Daemon in Java

Question

I have a MyThread object which I instantiate when my app is loaded through the server, I mark it as a Daemon thread and then call start() on it. The thread is m

Answer 1

If you're using a scheduled executor, you can provide a ThreadFactory. This is used to create new Threads, and you can modify these (e.g. make them daemon) as you require.

EDIT: To answer your update, your ThreadFactory just needs to implement newThread(Runnable r) since your WebRunnable is a Runnable. So no real extra work.

Answer 2

Just to complement with another possible solution for completeness. It may not be as nice though.

final Executor executor = Executors.newSingleThreadExecutor();
Runtime.getRuntime().addShutdownHook(new Thread() {

    @Override
    public void run() {
        executor.shutdownNow();
    }
});

Answer 3

Check out the JavaDoc for newSingleThreadScheduledExecutor(ThreadFactory threadFactory)

It would be implemented something like this:

public class MyClass { 
    private DaemonThreadFactory dtf = new DaemonThreadFactory();
    private ScheduledExecutorService executor = 
                                 Executors.newSingleThreadScheduledExecutor(dtf);
    // ....class stuff.....
    // ....Instance the runnable.....
    // ....submit() to executor....
}

class DaemonThreadFactory implements ThreadFactory {
    public Thread newThread(Runnable r) {
        Thread thread = new Thread(r);
        thread.setDaemon(true);
        return thread;
    }
}