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ExecutorService shutdownAndAwaitTermination()

hi guys

Was reading up the ExecutorService API
http://docs.oracle.com/javase/6/docs/api/java/util/concurrent/ExecutorService.html

Was trying to understand what shutdownAndAwaitTermination() method does and
do we need to use it everytime we use ExecutroService?

Below is my scenario

...
...
executor.submit(myTask); --> i am submitting task to executor
...
shutdownAndAwaitTermination(executor); -- finally i am calling shutdownAndAwaitTermination()
...
...

//taken from java doc
shutdownAndAwaitTermination(ExecutorService pool)
void shutdownAndAwaitTermination(ExecutorService pool) {
pool.shutdown();//once the above task has been executed by threads,shut down executor ?
try {
// Wait 60 seconds for existing tasks to terminate
if (!pool.awaitTermination(60, TimeUnit.SECONDS)) { //--what does this do?
pool.shutdownNow(); // Cancel currently executing tasks

if (!pool.awaitTermination(60, TimeUnit.SECONDS))
System.err.println("Pool did not terminate");
}
} catch (InterruptedException ie) {
// (Re-)Cancel if current thread also interrupted
pool.shutdownNow();
Thread.currentThread().interrupt();--what does this do?
}
}

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nareshvoota

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Jay Roy

ASKER

thanks,
I find it little confusing.
You say
>>If another thread called interrupt on this thread, pool.awaitTermination will throw Interrupted exception and clears the interrupted status on the thread

static boolean interrupted() method clears the interrupted status and not the void interrupt() method, correct?

My question is in comments:

--taken from java doc
shutdownAndAwaitTermination(ExecutorService pool)
void shutdownAndAwaitTermination(ExecutorService pool) {
pool.shutdown();
try {
if (!pool.awaitTermination(60, TimeUnit.SECONDS)) { //this is a blocking method, so an interrupted exception is thrown, correct?
pool.shutdownNow();
if (!pool.awaitTermination(60, TimeUnit.SECONDS))
System.err.println("Pool did not terminate");
}
} catch (InterruptedException ie) {
// (Re-)Cancel if current thread also interrupted
pool.shutdownNow();
Thread.currentThread().interrupt(); // Most importantly i want to know what does this do?
}
}

If you can tell me what happens step - by - step that will be great.

thanks