protected void handleTaskSubmittedRequest(
Runnable runnable, Address source, long requestId, long threadId) {
// We store in our map so that when that task is
// finished so that we can send back to the owner
// with the results
_running.put(runnable, new Owner(source, requestId));
// We give the task to the thread that is now waiting for it to be returned
// If we can't offer then we have to respond back to
// caller that we can't handle it. They must have
// gotten our address when we had a consumer, but
// they went away between then and now.
boolean received;
try {
_tasks.put(threadId, runnable);
CyclicBarrier barrier = _taskBarriers.remove(threadId);
if (received = (barrier != null)) {
// Only wait 10 milliseconds, in case if the consumer was
// stopped between when we were told it was available and now
barrier.await(10, TimeUnit.MILLISECONDS);
}
} catch (InterruptedException e) {
if (log.isDebugEnabled()) log.debug("Interrupted while handing off task");
Thread.currentThread().interrupt();
received = false;
} catch (BrokenBarrierException e) {
if (log.isDebugEnabled())
log.debug(
"Consumer " + threadId + " has been interrupted, " + "must retry to submit elsewhere");
received = false;
} catch (TimeoutException e) {
if (log.isDebugEnabled())
log.debug("Timeout waiting to hand off to barrier, consumer " + threadId + " must be slow");
// This should only happen if the consumer put the latch then got
// interrupted but hadn't yet removed the latch, should almost never
// happen
received = false;
}
if (!received) {
// Clean up the tasks request
_tasks.remove(threadId);
if (log.isDebugEnabled()) log.debug("Run rejected not able to pass off to consumer");
// If we couldn't hand off the task we have to tell the client
// and also reupdate the coordinator that our consumer is ready
sendRequest(source, Type.RUN_REJECTED, requestId, null);
_running.remove(runnable);
}
}
protected void handleConsumerReadyRequest(long requestId, Address address) {
Owner requestor;
final Owner source = new Owner(address, requestId);
_consumerLock.lock();
try {
requestor = _runRequests.poll();
// We don't add duplicate consumers - this allows for resubmission
// if it is thought the message may have been dropped
if (requestor == null && !_consumersAvailable.contains(source)) {
_consumersAvailable.add(source);
}
} finally {
_consumerLock.unlock();
}
if (requestor != null) {
sendRequest(
requestor.getAddress(), Type.CONSUMER_FOUND, source.getRequestId(), source.getAddress());
sendRemoveRunRequest(requestor);
} else {
sendNewConsumerRequest(source);
}
}
public Object down(Event evt) {
switch (evt.getType()) {
case ExecutorEvent.TASK_SUBMIT:
Runnable runnable = evt.getArg();
// We are limited to a number of concurrent request id's
// equal to 2^63-1. This is quite large and if it
// overflows it will still be positive
long requestId = Math.abs(counter.getAndIncrement());
if (requestId == Long.MIN_VALUE) {
// TODO: need to fix this it isn't safe for concurrent modifications
counter.set(0);
requestId = Math.abs(counter.getAndIncrement());
}
// Need to make sure to put the requestId in our map before
// adding the runnable to awaiting consumer in case if
// coordinator sent a consumer found and their original task
// is no longer around
// see https://issues.jboss.org/browse/JGRP-1744
_requestId.put(runnable, requestId);
_awaitingConsumer.add(runnable);
sendToCoordinator(RUN_REQUEST, requestId, local_addr);
break;
case ExecutorEvent.CONSUMER_READY:
Thread currentThread = Thread.currentThread();
long threadId = currentThread.getId();
_consumerId.put(threadId, PRESENT);
try {
for (; ; ) {
CyclicBarrier barrier = new CyclicBarrier(2);
_taskBarriers.put(threadId, barrier);
// We only send to the coordinator that we are ready after
// making the barrier, wait for request to come and let
// us free
sendToCoordinator(Type.CONSUMER_READY, threadId, local_addr);
try {
barrier.await();
break;
} catch (BrokenBarrierException e) {
if (log.isDebugEnabled())
log.debug(
"Producer timed out before we picked up"
+ " the task, have to tell coordinator"
+ " we are still good.");
}
}
// This should always be non nullable since the latch
// was freed
runnable = _tasks.remove(threadId);
_runnableThreads.put(runnable, currentThread);
return runnable;
} catch (InterruptedException e) {
if (log.isDebugEnabled()) log.debug("Consumer " + threadId + " stopped via interrupt");
sendToCoordinator(Type.CONSUMER_UNREADY, threadId, local_addr);
Thread.currentThread().interrupt();
} finally {
// Make sure the barriers are cleaned up as well
_taskBarriers.remove(threadId);
_consumerId.remove(threadId);
}
break;
case ExecutorEvent.TASK_COMPLETE:
Object arg = evt.getArg();
Throwable throwable = null;
if (arg instanceof Object[]) {
Object[] array = (Object[]) arg;
runnable = (Runnable) array[0];
throwable = (Throwable) array[1];
} else {
runnable = (Runnable) arg;
}
Owner owner = _running.remove(runnable);
// This won't remove anything if owner doesn't come back
_runnableThreads.remove(runnable);
Object value = null;
boolean exception = false;
if (throwable != null) {
// InterruptedException is special telling us that
// we interrupted the thread while waiting but still got
// a task therefore we have to reject it.
if (throwable instanceof InterruptedException) {
if (log.isDebugEnabled())
log.debug("Run rejected due to interrupted exception returned");
sendRequest(owner.address, Type.RUN_REJECTED, owner.requestId, null);
break;
}
value = throwable;
exception = true;
} else if (runnable instanceof RunnableFuture<?>) {
RunnableFuture<?> future = (RunnableFuture<?>) runnable;
boolean interrupted = false;
boolean gotValue = false;
// We have the value, before we interrupt at least get it!
while (!gotValue) {
try {
value = future.get();
gotValue = true;
} catch (InterruptedException e) {
interrupted = true;
} catch (ExecutionException e) {
value = e.getCause();
exception = true;
gotValue = true;
}
}
if (interrupted) {
Thread.currentThread().interrupt();
}
}
if (owner != null) {
final Type type;
final Object valueToSend;
if (value == null) {
type = Type.RESULT_SUCCESS;
valueToSend = value;
}
// Both serializable values and exceptions would go in here
else if (value instanceof Serializable
|| value instanceof Externalizable
|| value instanceof Streamable) {
type = exception ? Type.RESULT_EXCEPTION : Type.RESULT_SUCCESS;
valueToSend = value;
}
// This would happen if the value wasn't serializable,
// so we have to send back to the client that the class
// wasn't serializable
else {
type = Type.RESULT_EXCEPTION;
valueToSend = new NotSerializableException(value.getClass().getName());
}
if (local_addr.equals(owner.getAddress())) {
if (log.isTraceEnabled())
log.trace(
"[redirect] <--> ["
+ local_addr
+ "] "
+ type.name()
+ " ["
+ value
+ (owner.requestId != -1 ? " request id: " + owner.requestId : "")
+ "]");
if (type == Type.RESULT_SUCCESS) {
handleValueResponse(local_addr, owner.requestId, valueToSend);
} else if (type == Type.RESULT_EXCEPTION) {
handleExceptionResponse(local_addr, owner.requestId, (Throwable) valueToSend);
}
} else {
sendRequest(owner.getAddress(), type, owner.requestId, valueToSend);
}
} else {
if (log.isTraceEnabled()) {
log.trace("Could not return result - most likely because it was interrupted");
}
}
break;
case ExecutorEvent.TASK_CANCEL:
Object[] array = evt.getArg();
runnable = (Runnable) array[0];
if (_awaitingConsumer.remove(runnable)) {
_requestId.remove(runnable);
ExecutorNotification notification = notifiers.remove(runnable);
if (notification != null) {
notification.interrupted(runnable);
}
if (log.isTraceEnabled())
log.trace("Cancelled task " + runnable + " before it was picked up");
return Boolean.TRUE;
}
// This is guaranteed to not be null so don't take cost of auto unboxing
else if (array[1] == Boolean.TRUE) {
owner = removeKeyForValue(_awaitingReturn, runnable);
if (owner != null) {
Long requestIdValue = _requestId.remove(runnable);
// We only cancel if the requestId is still available
// this means the result hasn't been returned yet and
// we still have a chance to interrupt
if (requestIdValue != null) {
if (requestIdValue != owner.getRequestId()) {
log.warn("Cancelling requestId didn't match waiting");
}
sendRequest(owner.getAddress(), Type.INTERRUPT_RUN, owner.getRequestId(), null);
}
} else {
if (log.isTraceEnabled()) log.warn("Couldn't interrupt server task: " + runnable);
}
ExecutorNotification notification = notifiers.remove(runnable);
if (notification != null) {
notification.interrupted(runnable);
}
return Boolean.TRUE;
} else {
return Boolean.FALSE;
}
case ExecutorEvent.ALL_TASK_CANCEL:
array = evt.getArg();
// This is a RunnableFuture<?> so this cast is okay
@SuppressWarnings("unchecked")
Set<Runnable> runnables = (Set<Runnable>) array[0];
Boolean booleanValue = (Boolean) array[1];
List<Runnable> notRan = new ArrayList<>();
for (Runnable cancelRunnable : runnables) {
// Removed from the consumer
if (!_awaitingConsumer.remove(cancelRunnable) && booleanValue == Boolean.TRUE) {
synchronized (_awaitingReturn) {
owner = removeKeyForValue(_awaitingReturn, cancelRunnable);
if (owner != null) {
Long requestIdValue = _requestId.remove(cancelRunnable);
if (requestIdValue != owner.getRequestId()) {
log.warn("Cancelling requestId didn't match waiting");
}
sendRequest(owner.getAddress(), Type.INTERRUPT_RUN, owner.getRequestId(), null);
}
ExecutorNotification notification = notifiers.remove(cancelRunnable);
if (notification != null) {
log.trace("Notifying listener");
notification.interrupted(cancelRunnable);
}
}
} else {
_requestId.remove(cancelRunnable);
notRan.add(cancelRunnable);
}
}
return notRan;
case Event.SET_LOCAL_ADDRESS:
local_addr = evt.getArg();
break;
case Event.VIEW_CHANGE:
handleView(evt.getArg());
break;
}
return down_prot.down(evt);
}