com.ibm.able.rules
Class AblePatternMatchNetwork

java.lang.Object
  com.ibm.able.rules.AblePatternMatchNetwork

All Implemented Interfaces:

AbleClearable, AbleWorkingMemory, java.io.Serializable

public class AblePatternMatchNetwork

extends java.lang.Object

implements AbleWorkingMemory, AbleClearable, java.io.Serializable

This class is the run-time instance of a Rete' network and associated working memory constructed and used by the AblePatternMatchEngine.

The AblePatternMatchNetwork class plays two roles, first as the compiled sorting network (Rete' network) of alpha and beta nodes (AblePatternMatchNodes and subclasses), and as an AbleWorkingMemory or object data store.

A single AbleRuleBlock or set of AblePatternMatchRules is compiled into the Rete' network structure. Subsequent assert, retract, or modify operations against the AblePatternMatchNetwork cause Tokens to be created and passed through the network for processing.

See Also:

AblePatternMatchRule, AblePatternMatchEngine, Serialized Form

Field Summary

protected java.util.HashSet	allTerminalNodes
protected int	index
protected java.util.Hashtable	joinNodes Holds all of the positive, negative, and And Join nodes with beta memories
protected AbleRuleSet	myRuleSet
protected AbleLogger	myTracer
protected static AbleExpression	myTrueExpression
protected boolean	noDuplicates
protected java.util.Hashtable	rootNodeHash
protected java.util.Hashtable	selectorVarHash
protected java.util.Hashtable	terminalNodes Holds the associated Terminal node for each selector (pattern) and rule
protected AbleWorkingMemory	workingMemory

Constructor Summary

AblePatternMatchNetwork(AbleRuleSet theRuleSet, AbleRuleBlock theRules, AbleLogger theTracer, AbleWorkingMemory memory)

Method Summary

boolean	asserta(java.lang.Object fact) Place a fact into the working memory at front.
void	assertAll(java.util.List theList) Assert all elements in the list into working memory.
boolean	assertFact(java.lang.Object fact) A new memory element was added to the working memory -- update the PM network
boolean	assertz(java.lang.Object fact) Place a fact into the database at end.
void	clear() Remove all objects stored in this working memory
protected void	compileNetwork(AbleRuleBlock theRules) Build a pattern match network from a set of when/do rules
void	dumpNetwork() Debugging method to output structure of PatternMatch Network after compilation.
protected void	dumpNode(com.ibm.able.rules.AblePatternMatchNode node) Recursively display Nodes connected to this one.
boolean	exists(java.lang.Object fact) Test if the specified object exists in the working memory.
java.lang.Object	find(AbleSelector query) Given a query which is a pattern match rule Return the first object that matches the constraints
java.util.AbstractCollection	findAll(AbleSelector query) Given a query which is a pattern match rule Return the all objects that match the constraints
java.util.AbstractCollection	findAllInstances(java.lang.String className) Find all objects that match the class
protected com.ibm.able.rules.AblePatternMatchNode	generateAndJoinNode(com.ibm.able.rules.AblePatternMatchNode parentNode1, com.ibm.able.rules.AblePatternMatchNode parentNode2, AbleExpression testExpression, AbleVariable selectorVar, java.util.Vector selectorVars) Create a two-input AND (join) pattern match node
protected com.ibm.able.rules.AblePatternMatchNode	generateDummyJoinNode(com.ibm.able.rules.AblePatternMatchNode parentNode2, AbleExpression testExpression, AbleVariable selectorVar, java.util.Vector selectorVars) Create a two-input dummy (join) pattern match node Note: parentNode1 is always null
protected com.ibm.able.rules.AblePatternMatchNode	generateJoinNode(com.ibm.able.rules.AblePatternMatchNode parentNode1, com.ibm.able.rules.AblePatternMatchNode parentNode2, AbleExpression testExpression, AbleVariable selectorVar, java.util.Vector selectorVars) Create a two-input (join) pattern match node
protected com.ibm.able.rules.AblePatternMatchNode	generateNegativeSelectorNodes(com.ibm.able.rules.AblePatternMatchRootNode theRootNode, com.ibm.able.rules.AblePatternMatchNode theLastNode, AbleSelector lastSelector, AbleSelector theSelector, java.util.Vector selectorVars) Generate the PatternMatchNodes for this negative selector (pattern)
protected com.ibm.able.rules.AblePatternMatchNode	generateNegJoinNode(com.ibm.able.rules.AblePatternMatchNode parentNode1, com.ibm.able.rules.AblePatternMatchNode parentNode2, AbleExpression testExpression, AbleVariable selectorVar, java.util.Vector selectorVars) Create a two-input (join) pattern match node
protected com.ibm.able.rules.AblePatternMatchNode	generatePositiveSelectorNodes(com.ibm.able.rules.AblePatternMatchRootNode theRootNode, com.ibm.able.rules.AblePatternMatchNode theLastNode, AbleSelector lastSelector, AbleSelector theSelector, java.util.Vector selectorVars) Generate the PatternMatchNodes for this positive selector (pattern)
protected void	generateRuleNodes(AblePatternMatchRule theRule) Generate the PatternMatchNodes for this rule
protected com.ibm.able.rules.AblePatternMatchNode	generateRuleTerminalNode(com.ibm.able.rules.AblePatternMatchNode parentNode, AblePatternMatchRule theRule) Create a rule terminal node
protected com.ibm.able.rules.AblePatternMatchNode	generateTerminalNode(com.ibm.able.rules.AblePatternMatchNode parentNode, AbleVariable selectorVar) Create a terminal node
protected com.ibm.able.rules.AblePatternMatchNode	generateTestNode(com.ibm.able.rules.AblePatternMatchNode parentNode, AbleExpression testExpression, AbleVariable selectorVar) Create a one-input (test) pattern match node
protected com.ibm.able.rules.AblePatternMatchNode	generateTestNodes(com.ibm.able.rules.AblePatternMatchNode parentNode, AbleExpression testExpression, AbleVariable selectorVar) Create a sequence of ANDed one-input (test) pattern match nodes
java.util.Enumeration	getClasses() Retrieve all classes (types) stored in this working memory
protected int	getNumInputs(AbleExpression expression, java.util.Vector selectorVars)
boolean	isEmpty() Returns true if the working memory is empty (contains no objects)
void	modify(java.lang.Object fact) Modify or change an existing memory element A memory element was changed in the the working memory - update the PM net
void	modifyFact(java.lang.Object fact) Modify or change an existing fact in the database
void	retract(java.lang.Object fact) A memory element was removed from the working memory - update the PM Network
void	retractAll(java.util.List theList) Retract all elements in the list from working memory.
void	retractFact(java.lang.Object fact) Remove a fact from the database
protected void	setReplacementVars(java.util.Vector selectorVars, java.util.Hashtable replacementVars, java.util.Vector newSelectorVars)
java.lang.Object[]	toArray() Format the contents of working memory as an array of String[] Able array variables Note: this is an expensive operation
java.lang.String	toString() Format the contents of working memory into a String For display in an Inspector

Methods inherited from class java.lang.Object

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

Field Detail

rootNodeHash

protected java.util.Hashtable rootNodeHash

workingMemory

protected AbleWorkingMemory workingMemory

index

protected int index

selectorVarHash

protected java.util.Hashtable selectorVarHash

noDuplicates

protected boolean noDuplicates

terminalNodes

protected java.util.Hashtable terminalNodes

Holds the associated Terminal node for each selector (pattern) and rule

allTerminalNodes

protected java.util.HashSet allTerminalNodes

joinNodes

protected java.util.Hashtable joinNodes

Holds all of the positive, negative, and And Join nodes with beta memories

myTracer

protected AbleLogger myTracer

myRuleSet

protected AbleRuleSet myRuleSet

myTrueExpression

protected static final AbleExpression myTrueExpression

Constructor Detail

AblePatternMatchNetwork

public AblePatternMatchNetwork(AbleRuleSet theRuleSet,
                               AbleRuleBlock theRules,
                               AbleLogger theTracer,
                               AbleWorkingMemory memory)
                        throws AbleException

Method Detail

compileNetwork

protected void compileNetwork(AbleRuleBlock theRules)
                       throws AbleException

Build a pattern match network from a set of when/do rules

Throws:

AbleException

generateRuleNodes

protected void generateRuleNodes(AblePatternMatchRule theRule)
                          throws AbleException

Generate the PatternMatchNodes for this rule

Throws:

AbleException

generatePositiveSelectorNodes

protected com.ibm.able.rules.AblePatternMatchNode generatePositiveSelectorNodes(com.ibm.able.rules.AblePatternMatchRootNode theRootNode,
                                                                                com.ibm.able.rules.AblePatternMatchNode theLastNode,
                                                                                AbleSelector lastSelector,
                                                                                AbleSelector theSelector,
                                                                                java.util.Vector selectorVars)
                                                                         throws AbleDataException

Generate the PatternMatchNodes for this positive selector (pattern)

Throws:

AbleDataException

getNumInputs

protected int getNumInputs(AbleExpression expression,
                           java.util.Vector selectorVars)

setReplacementVars

protected void setReplacementVars(java.util.Vector selectorVars,
                                  java.util.Hashtable replacementVars,
                                  java.util.Vector newSelectorVars)

generateNegativeSelectorNodes

protected com.ibm.able.rules.AblePatternMatchNode generateNegativeSelectorNodes(com.ibm.able.rules.AblePatternMatchRootNode theRootNode,
                                                                                com.ibm.able.rules.AblePatternMatchNode theLastNode,
                                                                                AbleSelector lastSelector,
                                                                                AbleSelector theSelector,
                                                                                java.util.Vector selectorVars)
                                                                         throws AbleDataException

Generate the PatternMatchNodes for this negative selector (pattern)

Throws:

AbleDataException

generateTestNodes

protected com.ibm.able.rules.AblePatternMatchNode generateTestNodes(com.ibm.able.rules.AblePatternMatchNode parentNode,
                                                                    AbleExpression testExpression,
                                                                    AbleVariable selectorVar)

Create a sequence of ANDed one-input (test) pattern match nodes

generateTestNode

protected com.ibm.able.rules.AblePatternMatchNode generateTestNode(com.ibm.able.rules.AblePatternMatchNode parentNode,
                                                                   AbleExpression testExpression,
                                                                   AbleVariable selectorVar)

Create a one-input (test) pattern match node

generateDummyJoinNode

protected com.ibm.able.rules.AblePatternMatchNode generateDummyJoinNode(com.ibm.able.rules.AblePatternMatchNode parentNode2,
                                                                        AbleExpression testExpression,
                                                                        AbleVariable selectorVar,
                                                                        java.util.Vector selectorVars)

Create a two-input dummy (join) pattern match node Note: parentNode1 is always null

generateAndJoinNode

protected com.ibm.able.rules.AblePatternMatchNode generateAndJoinNode(com.ibm.able.rules.AblePatternMatchNode parentNode1,
                                                                      com.ibm.able.rules.AblePatternMatchNode parentNode2,
                                                                      AbleExpression testExpression,
                                                                      AbleVariable selectorVar,
                                                                      java.util.Vector selectorVars)

Create a two-input AND (join) pattern match node

generateJoinNode

protected com.ibm.able.rules.AblePatternMatchNode generateJoinNode(com.ibm.able.rules.AblePatternMatchNode parentNode1,
                                                                   com.ibm.able.rules.AblePatternMatchNode parentNode2,
                                                                   AbleExpression testExpression,
                                                                   AbleVariable selectorVar,
                                                                   java.util.Vector selectorVars)

Create a two-input (join) pattern match node

generateNegJoinNode

protected com.ibm.able.rules.AblePatternMatchNode generateNegJoinNode(com.ibm.able.rules.AblePatternMatchNode parentNode1,
                                                                      com.ibm.able.rules.AblePatternMatchNode parentNode2,
                                                                      AbleExpression testExpression,
                                                                      AbleVariable selectorVar,
                                                                      java.util.Vector selectorVars)

Create a two-input (join) pattern match node

generateTerminalNode

protected com.ibm.able.rules.AblePatternMatchNode generateTerminalNode(com.ibm.able.rules.AblePatternMatchNode parentNode,
                                                                       AbleVariable selectorVar)

Create a terminal node

generateRuleTerminalNode

protected com.ibm.able.rules.AblePatternMatchNode generateRuleTerminalNode(com.ibm.able.rules.AblePatternMatchNode parentNode,
                                                                           AblePatternMatchRule theRule)

Create a rule terminal node

assertFact

public boolean assertFact(java.lang.Object fact)

A new memory element was added to the working memory -- update the PM network

Specified by:

assertFact in interface AbleWorkingMemory

asserta

public boolean asserta(java.lang.Object fact)

Description copied from interface: AbleWorkingMemory

Place a fact into the working memory at front. Return true if a new fact.

Specified by:

asserta in interface AbleWorkingMemory

assertz

public boolean assertz(java.lang.Object fact)

Description copied from interface: AbleWorkingMemory

Place a fact into the database at end. Return true if a new fact.

Specified by:

assertz in interface AbleWorkingMemory

assertAll

public void assertAll(java.util.List theList)

Assert all elements in the list into working memory. The list is unchanged.

Specified by:

assertAll in interface AbleWorkingMemory

Parameters:

theList - The list from which elements are to be asserted.

retractFact

public void retractFact(java.lang.Object fact)

Description copied from interface: AbleWorkingMemory

Remove a fact from the database

Specified by:

retractFact in interface AbleWorkingMemory

retract

public void retract(java.lang.Object fact)

A memory element was removed from the working memory - update the PM Network

Specified by:

retract in interface AbleWorkingMemory

retractAll

public void retractAll(java.util.List theList)

Retract all elements in the list from working memory. The list is unchanged.

Specified by:

retractAll in interface AbleWorkingMemory

Parameters:

theList - The list from which elements are to be retracted.

modifyFact

public void modifyFact(java.lang.Object fact)

Description copied from interface: AbleWorkingMemory

Modify or change an existing fact in the database

Specified by:

modifyFact in interface AbleWorkingMemory

modify

public void modify(java.lang.Object fact)

Modify or change an existing memory element A memory element was changed in the the working memory - update the PM net

Specified by:

modify in interface AbleWorkingMemory

exists

public boolean exists(java.lang.Object fact)

Test if the specified object exists in the working memory.

Specified by:

exists in interface AbleWorkingMemory

Parameters:

fact - The object we are looking for in the working memory.

Returns:

true if the object was found, false otherwise

find

public java.lang.Object find(AbleSelector query)
                      throws AbleDataException

Given a query which is a pattern match rule Return the first object that matches the constraints

Specified by:

find in interface AbleWorkingMemory

Throws:

AbleDataException

findAll

public java.util.AbstractCollection findAll(AbleSelector query)
                                     throws AbleDataException

Given a query which is a pattern match rule Return the all objects that match the constraints

Specified by:

findAll in interface AbleWorkingMemory

Throws:

AbleDataException

findAllInstances

public java.util.AbstractCollection findAllInstances(java.lang.String className)

Find all objects that match the class

Specified by:

findAllInstances in interface AbleWorkingMemory

getClasses

public java.util.Enumeration getClasses()

Retrieve all classes (types) stored in this working memory

Specified by:

getClasses in interface AbleWorkingMemory

clear

public void clear()

Remove all objects stored in this working memory

Specified by:

clear in interface AbleWorkingMemory

isEmpty

public boolean isEmpty()

Returns true if the working memory is empty (contains no objects)

Specified by:

isEmpty in interface AbleWorkingMemory

dumpNetwork

public void dumpNetwork()

Debugging method to output structure of PatternMatch Network after compilation. Trace assumed on.

dumpNode

protected void dumpNode(com.ibm.able.rules.AblePatternMatchNode node)

Recursively display Nodes connected to this one. Assumes trace on.

toString

public java.lang.String toString()

Format the contents of working memory into a String For display in an Inspector

toArray

public java.lang.Object[] toArray()
                           throws AbleDataException

Format the contents of working memory as an array of String[] Able array variables Note: this is an expensive operation

Specified by:

toArray in interface AbleWorkingMemory

Throws:

AbleDataException