edu.mit.sketch.system
Class Blackboard

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

public class Blackboard

extends Observable

The blackboard is the central datastructure for all the information we have collected about the sketch and our interpretations of it. It also provides a variety of ways to access the data in the BB according to space, time, whether or not it is part of the current display, etc... It is inspired by and shares many similarities with the Hearsay II architecture. The newUserInput method is the entry point of all user generated items into the system (i.e. strokes and utterances).

Created: Tue Nov 20 15:52:44 2001
Copyright: Copyright (C) 2001 by MIT. All Rights Reserved.

Constructor Summary

Blackboard()

Method Summary

void	addItem(BBItem item, Collection supports) This method is used by KS and the scheduler to add elements to the BB.
void	addTemplate(Template t)
SketchItemIndex	getAllItems() Get all of the item that the system knows about.
InterpretationIndex	getInterpretationIndex()
SketchItemIndex	getItems(BBItemType type) Get all the BBItems of a given type from the blackboard
Set	getTemplatesFor(BBItem item)
String	toString()

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, wait, wait, wait

Constructor Detail

Blackboard

public Blackboard()

Method Detail

getAllItems

public SketchItemIndex getAllItems()

Get all of the item that the system knows about.

getInterpretationIndex

public InterpretationIndex getInterpretationIndex()

getItems

public SketchItemIndex getItems(BBItemType type)

Get all the BBItems of a given type from the blackboard

addItem

public void addItem(BBItem item,
                    Collection supports)

This method is used by KS and the scheduler to add elements to the BB. It should not be called directly by any UI code (for elements such as strokes or utterances). Instead they should call BlackhoardSystem#newUserInput(BBItem)

Parameters:

item - BBItem to add to the BB.

supports - a Collection containing the BB items that support this new item

See Also:

#newUserInput( BBItem item )

addTemplate

public void addTemplate(Template t)

getTemplatesFor

public Set getTemplatesFor(BBItem item)

toString

public String toString()

Overrides:

toString in class Object