Shutting down consumer thread when producer is finished

[Theodore David Williams]

I am using an ArrayBlockingQueue.

A producer loops over some data and inserts into the queue until end of data.

The consumer 'takes' from the queue until it receives a shutdown(i.e. the producer is finished) and the queue is empty(i.e. it is done processing all entires in the queue)

Producer pseudo code

    
for (Data d : allData) {
   queue.put(d);
}

// I am done let consumer know
consumer.shutdown()

Consumer pseudo code

   
.
.
// consume data while not told to stop,
// when told to stop, keeping looping until all data is consumed
while(!(shutdown && queue.isEmpty()) {
   Data d = queue.take();
   // do something with data
} 
.
.

public void shutdown() {
   shutdown = true;
}

This works as I would expect except for when I call shutdown in the producer I have no idea how long it will take the consumer to process what was left in the queue and actually finish.

Is there a good wait to wait/block on the shutdown call such that when that call returns I know the consumer thread is finished?

[Jelle Klap]

You could use an ExecutorService to fire up and shutdown the producer and consumer. HAve a look at its API, specifically the shutdown() / shutdownNow() and awaitTermination() methods.
An other way would be to use a "poison pill". When the producer is finished have it produce an object that is recognizable to the consumer as a shutdown indicator. That can get a bit involved though, when you have multiple producers and consumers hooked up to the same queue.