Does a Future timeout kill the Thread execution

java concurrency executorservice future
Nico Huysamen picture Nico Huysamen · Apr 26, 2013 · Viewed 54.9k times · Source

When using an ExecutorService and Future objects (when submitting Runnable tasks), if I specify a timeout value to the future's get function, does the underlying thread get killed when a TimeoutException is thrown?

Answer

Eugene picture Eugene · Apr 26, 2013

It does not. Why would it? Unless you tell it to.

There is a very valid concern here in case of a Callable for example. If you waited for the result for say 20 seconds and you did not get it, then you are not interested in the result anymore. At that time you should cancel the task at all.

Something like this:

Future<?> future = service.submit(new MyCallable());
    try {
        future.get(100, TimeUnit.MILLISECONDS);
    } catch (Exception e){
        e.printStackTrace();
        future.cancel(true); //this method will stop the running underlying task
    }

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