/* This test checks whether dispatcher hangs on close if following two things
* happen :
* 1. A thread which was putting event to event queue is interrupted.
* 2. Event queue is empty on close.
*/
/// <exception cref="System.Exception"/>
public virtual void TestDispatcherOnCloseIfQueueEmpty()
{
BlockingQueue <Org.Apache.Hadoop.Yarn.Event.Event> eventQueue = Org.Mockito.Mockito.Spy
(new LinkedBlockingQueue <Org.Apache.Hadoop.Yarn.Event.Event>());
Org.Apache.Hadoop.Yarn.Event.Event @event = Org.Mockito.Mockito.Mock <Org.Apache.Hadoop.Yarn.Event.Event
>();
Org.Mockito.Mockito.DoThrow(new Exception()).When(eventQueue).Put(@event);
DrainDispatcher disp = new DrainDispatcher(eventQueue);
disp.Init(new Configuration());
disp.SetDrainEventsOnStop();
disp.Start();
// Wait for event handler thread to start and begin waiting for events.
disp.WaitForEventThreadToWait();
try
{
disp.GetEventHandler().Handle(@event);
NUnit.Framework.Assert.Fail("Expected YarnRuntimeException");
}
catch (YarnRuntimeException e)
{
NUnit.Framework.Assert.IsTrue(e.InnerException is Exception);
}
// Queue should be empty and dispatcher should not hang on close
NUnit.Framework.Assert.IsTrue("Event Queue should have been empty", eventQueue.IsEmpty
());
disp.Close();
}
protected internal override void Dispatch(Org.Apache.Hadoop.Yarn.Event.Event @event
)
{
Log.Info("Dispatching the event " + @event.GetType().FullName + "." + @event.ToString
());
Type type = @event.GetType().GetDeclaringClass();
if (eventDispatchers[type] != null)
{
eventDispatchers[type].Handle(@event);
}
}
protected internal virtual void Dispatch(Org.Apache.Hadoop.Yarn.Event.Event @event
)
{
//all events go thru this loop
if (Log.IsDebugEnabled())
{
Log.Debug("Dispatching the event " + @event.GetType().FullName + "." + @event.ToString
());
}
Type type = @event.GetType().GetDeclaringClass();
try
{
EventHandler handler = eventDispatchers[type];
if (handler != null)
{
handler.Handle(@event);
}
else
{
throw new Exception("No handler for registered for " + type);
}
}
catch (Exception t)
{
//TODO Maybe log the state of the queue
Log.Fatal("Error in dispatcher thread", t);
// If serviceStop is called, we should exit this thread gracefully.
if (exitOnDispatchException && (ShutdownHookManager.Get().IsShutdownInProgress())
== false && stopped == false)
{
Sharpen.Thread shutDownThread = new Sharpen.Thread(CreateShutDownThread());
shutDownThread.SetName("AsyncDispatcher ShutDown handler");
shutDownThread.Start();
}
}
}
public virtual void Handle(Org.Apache.Hadoop.Yarn.Event.Event @event)
{
this._enclosing.Dispatch(@event);
}
