edu.mit.sketch.system
Class StageBasedScheduler

java.lang.Object
  |
  +--java.util.Observable
        |
        +--edu.mit.sketch.system.Scheduler
              |
              +--edu.mit.sketch.system.StageBasedScheduler

public class StageBasedScheduler

extends Scheduler

I am calling this the Stage Based Scheduler because it chooses what knowledge source to run next in order of stages of processing that they pertain to. (i.e. low level, bottom up, top down... etc).

Created: Tue Feb 12 10:38:09 2002
Copyright: Copyright (C) 2001 by MIT. All rights reserved.

Fields inherited from class edu.mit.sketch.system.Scheduler

m_blackboard, m_items, m_ksManager, m_system, m_triggeredKSs

Constructor Summary

StageBasedScheduler(BlackboardSystem bbs)

Method Summary

protected SchedulerItem	chooseNextItem() This function is really the meat of the whole show.
protected boolean	doneProcessing() We are done if the stack is empty and there are no more unprocessed BBItems.
protected SchedulerItem	postProcessingStep() Ask if this particular scheduler has a post processing process to run.
protected boolean	readyToProcess() Very simple mechanism.

Methods inherited from class edu.mit.sketch.system.Scheduler

addNewBBItem, getRecentItems, hasUnprocessed, isStackEmpty, popStack, triggerKSs

Methods inherited from class java.util.Observable

addObserver, clearChanged, countObservers, deleteObserver, deleteObservers, hasChanged, notifyObservers, notifyObservers, setChanged

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

StageBasedScheduler

public StageBasedScheduler(BlackboardSystem bbs)

Method Detail

doneProcessing

protected boolean doneProcessing()

We are done if the stack is empty and there are no more unprocessed BBItems. This is likely a very common done condition.

Overrides:

doneProcessing in class Scheduler

chooseNextItem

protected SchedulerItem chooseNextItem()

This function is really the meat of the whole show. Here's how this one works: If there are things in the scheduling stack, do those. Otherwise, if there are new things on the blackboard see what new KSs can run. Select a KS by its procssing type: first LowLevel ones, then Bottom Up then Top Down, then whatever else (I have to figure out exactly how this is going to work still).

Overrides:

chooseNextItem in class Scheduler

postProcessingStep

protected SchedulerItem postProcessingStep()

Description copied from class: Scheduler

Ask if this particular scheduler has a post processing process to run.

Overrides:

postProcessingStep in class Scheduler

readyToProcess

protected boolean readyToProcess()

Very simple mechanism. Just process data every time we get it.

Overrides:

readyToProcess in class Scheduler