Hi folks,
I doubt that DrainDispatcher may have race condition.
Here's the sequence
1. eventQueue is empty and EventHandling Thread check the eventQueue and
set drained as true
2. new event is added to eventQueue, but has not been handled yet.
3. DrainDispatcher.await() is called, but at this time drained is true, so
await will exit at once. But actually there's still event not yet handled
in step 2.
Is the above sequence possible ? Do I miss something ? Thanks
while (!stopped && !Thread.currentThread().isInterrupted()) {
drained = eventQueue.isEmpty();
// blockNewEvents is only set when dispatcher is draining to stop,
// adding this check is to avoid the overhead of acquiring the
lock
// and calling notify every time in the normal run of the loop.
if (blockNewEvents) {
synchronized (waitForDrained) {
if (drained) {
waitForDrained.notify();
}
}
}
Event event;
try {
event = eventQueue.take();
} catch(InterruptedException ie) {
if (!stopped) {
LOG.warn("AsyncDispatcher thread interrupted", ie);
}
return;
}
if (event != null) {
dispatch(event);
}
}
