/// <summary>
/// Use the TaskExecutor to generate a result. The
/// internal state in this case is a queue of unfinished result holders of
/// IResultHolder. The holder with the return value should not be
/// on the queue when this method exits. The queue is scoped in the calling
/// method so there is no need to synchronize access.
/// </summary>
/// <param name="context"></param>
/// <param name="callback"></param>
/// <param name="state"></param>
/// <returns></returns>
protected override RepeatStatus GetNextResult(IRepeatContext context, RepeatCallback callback,
IRepeatInternalState state)
{
ExecutingRunnable runnable;
IResultQueue <IResultHolder> queue = ((ResultQueueInternalState)state).ResultQueue;
do
{
// Wrap the callback in a runnable that will add its result to the
// queue when it is ready.
runnable = new ExecutingRunnable(callback, context, queue);
// Tell the runnable that it can expect a result. This could have
// been in-lined with the constructor, but it might block, so it's
// better to do it here, since we have the option (it's a private
// class).
runnable.Expect();
//Start the task possibly concurrently / in the future.
_taskExecutor.Execute(new Task(delegate { runnable.Run(); }));
// Allow termination policy to update its state. This must happen
// immediately before or after the call to the task executor.
Update(context);
// Keep going until we get a result that is finished, or early
// termination...
}while (queue.IsEmpty() && !IsComplete(context));
IResultHolder result = queue.Take();
if (result.Error != null)
{
throw result.Error;
}
return(result.Result);
}
/// <summary>
/// Use the TaskExecutor to generate a result. The
/// internal state in this case is a queue of unfinished result holders of
/// IResultHolder. The holder with the return value should not be
/// on the queue when this method exits. The queue is scoped in the calling
/// method so there is no need to synchronize access.
/// </summary>
/// <param name="context"></param>
/// <param name="callback"></param>
/// <param name="state"></param>
/// <returns></returns>
protected override RepeatStatus GetNextResult(IRepeatContext context, RepeatCallback callback,
IRepeatInternalState state)
{
ExecutingRunnable runnable;
IResultQueue<IResultHolder> queue = ((ResultQueueInternalState)state).ResultQueue;
do
{
// Wrap the callback in a runnable that will add its result to the
// queue when it is ready.
runnable = new ExecutingRunnable(callback, context, queue);
// Tell the runnable that it can expect a result. This could have
// been in-lined with the constructor, but it might block, so it's
// better to do it here, since we have the option (it's a private
// class).
runnable.Expect();
//Start the task possibly concurrently / in the future.
_taskExecutor.Execute(new Task(delegate { runnable.Run(); }));
// Allow termination policy to update its state. This must happen
// immediately before or after the call to the task executor.
Update(context);
// Keep going until we get a result that is finished, or early
// termination...
}
while (queue.IsEmpty() && !IsComplete(context));
IResultHolder result = queue.Take();
if (result.Error != null)
{
throw result.Error;
}
return result.Result;
}