org.javades.jqueues.r5.util.predictor.workload

Interface WorkloadScheduleHandler

All Known Implementing Classes:

DefaultWorkloadSchedule, DefaultWorkloadSchedule_SQ_SV, DefaultWorkloadSchedule_SQ_SV_ROEL_U, SimQueueWithGateWorkloadScheduleHandler

public interface WorkloadScheduleHandler

A handler for specific SimJQEvent types as extension to a DefaultWorkloadSchedule.

The DefaultWorkloadSchedule deals with the basic external SimQueue events: queue-access vacations, arrivals, revocations, and server-access credits. However, it fails with a WorkloadScheduleInvalidException if it finds events in its input that it does not know about.

The handler-extension mechanism through DefaultWorkloadSchedule.registerHandler(org.javades.jqueues.r5.util.predictor.workload.WorkloadScheduleHandler) allows the registration of a handler, i.c., a WorkloadScheduleHandler, that manages a specific subset of SimJQEvent types (classes). An example of such an event is the SimQueueGateEvent for SimQueueWithGates. The extension mechanism is particularly useful for such state extensions to a SimQueue with accompanying SimJQEvents, especially for queues with multiple state extensions because (1) the complexity of DefaultWorkloadSchedule makes it unattractive for inheritance, and (2) the resulting subclasses would become increasingly complex given the fact that Java does not fully support multiple inheritance of implementation.

Author:

Jan de Jongh, TNO

Copyright (C) 2005-2017 Jan de Jongh, TNO

This file is covered by the LICENSE file in the root of this project.

See Also:

DefaultWorkloadSchedule, SimQueuePredictor_GATE

Method Summary

Modifier and Type	Method and Description
Map<Class<? extends SimJQEvent>,SimEntitySimpleEventType.Member>	getEventMap() Gets the set of SimJQEvents of this handler, and the SimEntitySimpleEventType members onto which they map.
String	getHandlerName() Returns the name of the handler.
boolean	needsScan() Whether or not this object needs to scan the DefaultWorkloadSchedule upon registration.
Set<SimJQEvent>	scan(DefaultWorkloadSchedule workloadSchedule) Scans the host DefaultWorkloadSchedule and builds internal data structures.

Method Detail

getHandlerName

String getHandlerName()

Returns the name of the handler.

The handler name must be unique within the realm of the DefaultWorkloadSchedule at which this handler registers. For SimQueue state extensions, the convention is to use the interface name appended with "Handler", like, "SimQueueHandler" and "SimQueueWithGateHandler".

Returns:

The name of the handler (must remain fixed during the handler's lifetime).

getEventMap

Map<Class<? extends SimJQEvent>,SimEntitySimpleEventType.Member> getEventMap()

Gets the set of SimJQEvents of this handler, and the SimEntitySimpleEventType members onto which they map.

The key-set should contains unique SimJQEvents within the realm of the DefaultWorkloadSchedule at which this handler registers. Likewise, the values should be unique.

Returns:

The set of SimJQEvents of this handler, and the SimEntitySimpleEventType members onto which they map.

needsScan

boolean needsScan()

Whether or not this object needs to scan the DefaultWorkloadSchedule upon registration.

Returns:

True if this handler needs to scan the host DefaultWorkloadSchedule upon registration.

See Also:

DefaultWorkloadSchedule.registerHandler(org.javades.jqueues.r5.util.predictor.workload.WorkloadScheduleHandler), scan(org.javades.jqueues.r5.util.predictor.workload.DefaultWorkloadSchedule)

scan

Set<SimJQEvent> scan(DefaultWorkloadSchedule workloadSchedule)
              throws WorkloadScheduleException

Scans the host DefaultWorkloadSchedule and builds internal data structures.

Called by our host DefaultWorkloadSchedule only upon registration, and if we ask for it needsScan().

Parameters:

workloadSchedule - The host at which we registered.

Returns:

The SimJQEvents processed by this handler, in a set with no particular member ordering; may be null or empty.

Throws:

WorkloadScheduleException - If the workload is invalid or ambiguous.

See Also:

DefaultWorkloadSchedule.registerHandler(org.javades.jqueues.r5.util.predictor.workload.WorkloadScheduleHandler), scan(org.javades.jqueues.r5.util.predictor.workload.DefaultWorkloadSchedule)