/// <summary>
/// Work performed by a worker thread.
/// </summary>
/// <remarks>
/// A worker thread executes the below until it receives a <see cref="PoisonPill"/>.
/// </remarks>
private void DoWork()
{
// Keep consuming until receive poison pill 'null' task
while (true)
{
IWork workToBeProcessed;
lock (this.queueLocker)
{
while (this.queue.Count == 0)
{
Monitor.Wait(this.queueLocker);
}
workToBeProcessed = this.queue.Dequeue();
if (ReferenceEquals(workToBeProcessed, POISON_PILL))
{
// Poison pill received - this signals our exit
break;
}
this.processing.Add(workToBeProcessed);
}
bool workSucceeded = false;
string workFailedMsg = string.Empty;
try
{
workToBeProcessed.Process();
workSucceeded = true;
}
catch (ApplicationException ex)
{
var message = string.Format("BackgroundWorkerQueue worker:{0}, Failed to process work:{1}",
Thread.CurrentThread.Name,
workToBeProcessed);
workFailedMsg = message;
}
catch (Exception)
{
var message = string.Format("BackgroundWorkerQueue worker:{0}, Unexpected exception while processing work:{1}",
Thread.CurrentThread.Name,
workToBeProcessed);
workFailedMsg = message;
}
lock (this.queueLocker)
{
this.processing.Remove(workToBeProcessed);
if (workSucceeded)
{
var args = new WorkSucceededProcessingEventArgs(workToBeProcessed);
this.OnWorkSucceeded(args);
}
else
{
this.HandleFailedWork(workToBeProcessed, workFailedMsg);
}
}
}
}
/// <summary>
/// Fires the <see cref="WorkSucceeded"/> events if any are registered.
/// </summary>
///
/// <param name="e">
/// The arguments for the event.
/// </param>
private void OnWorkSucceeded(WorkSucceededProcessingEventArgs e)
{
// This is done to avoid a threading issue.
var succeedEventListeners = this.WorkSucceeded;
if (succeedEventListeners != null)
{
this.WorkSucceeded(this, e);
}
}
void OnWorkSucceed(object sender, WorkSucceededProcessingEventArgs e)
{
this.Called = true;
}