I am trying to run the below concurrency code:
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
public class TestThread {
public static void main(final String[] arguments) throws InterruptedException {
ExecutorService executor = Executors.newSingleThreadExecutor();
try {
executor.submit(new Task());
System.out.println("Shutdown executor");
executor.shutdown();
executor.awaitTermination(5, TimeUnit.SECONDS);
} catch (InterruptedException e) {
System.err.println("tasks interrupted");
} finally {
if (!executor.isTerminated()) {
System.err.println("cancel non-finished tasks");
}
executor.shutdownNow();
System.out.println("shutdown finished");
}
}
static class Task implements Runnable {
public void run() {
try {
int duration = 6;
System.out.println("Running Task!");
TimeUnit.SECONDS.sleep(duration);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
and the output is :
Shutdown executor
Running Task!
shutdown finished
cancel non-finished tasks
java.lang.InterruptedException: sleep interrupted
at java.lang.Thread.sleep(Native Method)
at java.lang.Thread.sleep(Thread.java:340)
at java.util.concurrent.TimeUnit.sleep(TimeUnit.java:386)
at TestThread$Task.run(TestThread.java:34)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
According to the output it seems finally was not executed despite the try block getting completed. Am I right with the understanding? And why was the exception immediately thrown before going to the finally block?