ubc.cs.JLog.Terms
Class jQuadaryBuiltinPredicate

java.lang.Object
  ubc.cs.JLog.Foundation.jType
      ubc.cs.JLog.Terms.jTerm
          ubc.cs.JLog.Terms.iPredicate
              ubc.cs.JLog.Terms.jBuiltinPredicate
                  ubc.cs.JLog.Terms.jQuadaryBuiltinPredicate

All Implemented Interfaces:

iType, iUnifiable, iConsultable, iName, iNameArity, iTerm, iValue

Direct Known Subclasses:

jExpandTerm

public abstract class jQuadaryBuiltinPredicate
extends jBuiltinPredicate

Field Summary

protected jTerm	term1
protected jTerm	term2
protected jTerm	term3
protected jTerm	term4

Fields inherited from class ubc.cs.JLog.Foundation.jType

type

Fields inherited from interface ubc.cs.JLog.Terms.iTerm

EQUAL, GREATER_THAN, LESS_THAN

Fields inherited from interface ubc.cs.JLog.Foundation.iType

TYPE_ARITHMETIC, TYPE_ATOM, TYPE_BUILTINPREDICATE, TYPE_COMMAND, TYPE_COMPARE, TYPE_COMPOUND, TYPE_CONS, TYPE_IF, TYPE_INTEGER, TYPE_LIST, TYPE_NULLLIST, TYPE_NUMERICCOMPARE, TYPE_OBJECT, TYPE_OPERATOR, TYPE_OR, TYPE_ORPREDICATE, TYPE_PREDICATE, TYPE_PREDICATETERMS, TYPE_REAL, TYPE_TYPE, TYPE_UNARYARITHMETIC, TYPE_UNARYOPERATOR, TYPE_UNDEFINED, TYPE_VARIABLE

Constructor Summary

jQuadaryBuiltinPredicate(jTerm t1, jTerm t2, jTerm t3, jTerm t4, int t)

Method Summary

void	addGoals(jGoal g, iGoalStack goals) Adds goal to prove this predicate onto goal stack.
void	addGoals(jGoal g, jVariable[] vars, iGoalStack goals) Adds goal to prove this predicate onto goal stack.
protected int	compareArguments(iPredicate ipred, boolean first_call, boolean var_equal) Compares predicate aguments.
void	consult(jKnowledgeBase kb) Consult the given jKnowledgeBase and cache any invariant values (those which would not change until the next time the jKnowledgeBase changes).
void	consultReset() Called when the jKnowledgeBase changes.
jTerm	copy(jVariableRegistry vars) Internal member function which creates a copy of this term.
protected abstract jQuadaryBuiltinPredicate	duplicate(jTerm t1, jTerm t2, jTerm t3, jTerm t4)
jTerm	duplicate(jVariable[] vars) Creates a complete and entirely independant duplicate of this term.
void	enumerateVariables(jVariableVector v, boolean all) Adds variables belonging to this term (or belonging to any sub-part of this term) to the jVariableVector
protected boolean	equivalenceArguments(jBuiltinPredicate pterm, jEquivalenceMapping v) Equivalence test arguments.
jCompoundTerm	getArguments() Accessor for the arguments for this predicate.
int	getArity() Returns the arity of this instance.
jTerm	getTerm1()
jTerm	getTerm2()
jTerm	getTerm3()
jTerm	getTerm4()
boolean	isConsultNeeded() Determine if cached values already exist and hence if consulting is required.
boolean	prove(jQuadaryBuiltinPredicateGoal bg)
void	registerUnboundVariables(jUnifiedVector v) Adds any unbound variables belonging to this term (or belonging to any sub-part of this term) to the jUnifiedVector
void	registerVariables(jVariableVector v) Adds all variables belonging to this term (or belonging to any sub-part of this term) to the jUnifiedVector Should be called during the consultation phase by rules for their owned terms both head and base.
String	toString(boolean usename) Produces a string identifying this term, suitable for display to the console.
protected boolean	unifyArguments(jBuiltinPredicate pterm, jUnifiedVector v) Unification of arguments.

Methods inherited from class ubc.cs.JLog.Terms.jBuiltinPredicate

equivalence, unify

Methods inherited from class ubc.cs.JLog.Terms.iPredicate

compare

Methods inherited from class ubc.cs.JLog.Terms.jTerm

compare, copy, getName, getTerm, getValue, requiresCompleteVariableState, toString

Methods inherited from class ubc.cs.JLog.Foundation.jType

getType, objectToString

Methods inherited from class java.lang.Object

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

Methods inherited from interface ubc.cs.JLog.Terms.iName

getName

Field Detail

term1

protected jTerm term1

term2

protected jTerm term2

term3

protected jTerm term3

term4

protected jTerm term4

Constructor Detail

jQuadaryBuiltinPredicate

public jQuadaryBuiltinPredicate(jTerm t1,
                                jTerm t2,
                                jTerm t3,
                                jTerm t4,
                                int t)

Method Detail

getArity

public final int getArity()

Description copied from interface: iNameArity

Returns the arity of this instance.

Specified by:

getArity in interface iNameArity

Overrides:

getArity in class jBuiltinPredicate

Returns:

int whose value is the arity of this instance.

getTerm1

public final jTerm getTerm1()

getTerm2

public final jTerm getTerm2()

getTerm3

public final jTerm getTerm3()

getTerm4

public final jTerm getTerm4()

getArguments

public final jCompoundTerm getArguments()

Description copied from class: iPredicate

Accessor for the arguments for this predicate. Don't modify arguments after consult. Arguments are not guaranteed to be original so modifying has an unspecified effect.

Overrides:

getArguments in class iPredicate

Returns:

The original or possibly duplicated arguments for this predicate.

compareArguments

protected int compareArguments(iPredicate ipred,
                               boolean first_call,
                               boolean var_equal)

Description copied from class: jBuiltinPredicate

Compares predicate aguments. Override in classes with different arities.

Overrides:

compareArguments in class jBuiltinPredicate

Parameters:

ipred - the iPredicate to compare with this instance of iPredicate.

first_call - true if just invoked by public compare member function. false otherwise.

var_equal - if var_equal is true, then unbound variables are considered equal. var_equal = false is standard prolog behavior.

Returns:

LESS_THAN if this instance is less than term, EQUAL if the two terms are equal, and GREATER_THAN if this instance is greater than term.

equivalenceArguments

protected final boolean equivalenceArguments(jBuiltinPredicate pterm,
                                             jEquivalenceMapping v)

Description copied from class: jBuiltinPredicate

Equivalence test arguments. Similar behavior to that of equivalence.

Overrides:

equivalenceArguments in class jBuiltinPredicate

Parameters:

pterm - We are assured that pterm has the same type, name, and arity.

v - same as jEquivalenceMapping parameter in equivalence.

Returns:

Should test for instanceof as required and return false if there is no match, true otherwise.

unifyArguments

protected final boolean unifyArguments(jBuiltinPredicate pterm,
                                       jUnifiedVector v)

Description copied from class: jBuiltinPredicate

Unification of arguments. Similar behavior to that of unify.

Overrides:

unifyArguments in class jBuiltinPredicate

Parameters:

pterm - We are assured that pterm has the same type, name, and arity.

v - same as jUnifiedVector parameter in unify.

Returns:

Should test for instanceof as required and return false if there is no match, true otherwise.

registerVariables

public void registerVariables(jVariableVector v)

Description copied from class: jTerm

Adds all variables belonging to this term (or belonging to any sub-part of this term) to the jUnifiedVector Should be called during the consultation phase by rules for their owned terms both head and base. all variables encountered should be unbound. After call, this term should not be modified in any way.

Specified by:

registerVariables in interface iTerm

Overrides:

registerVariables in class jBuiltinPredicate

Parameters:

v - The jUnifiedVector where variables are added to. This parameter is used to as output to the caller, not as input.

enumerateVariables

public void enumerateVariables(jVariableVector v,
                               boolean all)

Description copied from class: jTerm

Adds variables belonging to this term (or belonging to any sub-part of this term) to the jVariableVector

Specified by:

enumerateVariables in interface iTerm

Overrides:

enumerateVariables in class jBuiltinPredicate

Parameters:

v - The jVariabeVector where variables are added to. This parameter is used to as output to the caller, not as input.

all - If true, then all variables should register, otherwise only add non-existentially qualified variables.

registerUnboundVariables

public void registerUnboundVariables(jUnifiedVector v)

Description copied from class: jTerm

Adds any unbound variables belonging to this term (or belonging to any sub-part of this term) to the jUnifiedVector

Specified by:

registerUnboundVariables in interface iTerm

Overrides:

registerUnboundVariables in class jTerm

Parameters:

v - The jUnifiedVector where unbound variables are added to. This parameter is used to as output to the caller, not as input.

prove

public boolean prove(jQuadaryBuiltinPredicateGoal bg)

addGoals

public void addGoals(jGoal g,
                     jVariable[] vars,
                     iGoalStack goals)

Description copied from class: iPredicate

Adds goal to prove this predicate onto goal stack. This version is called when the original predicate must duplicate itself (or its arguments). Add goals in the reverse order you want them evaluated.

Specified by:

addGoals in class iPredicate

Parameters:

g - The super-goal jGoal for the sub-goal that this function will add.

vars - The vector of duplicate variables produced from the previous call to registerVariables. Needed for call to duplicate.

goals - The iGoalStack to add the goal to.

addGoals

public void addGoals(jGoal g,
                     iGoalStack goals)

Description copied from class: iPredicate

Adds goal to prove this predicate onto goal stack. This version is called when the original predicate is already duplicated (usually as part of an argument for another predicate). Add goals in the reverse order you want them evaluated.

Specified by:

addGoals in class iPredicate

Parameters:

g - The super-goal jGoal for the sub-goal that this function will add.

goals - The iGoalStack to add the goal to.

duplicate

protected abstract jQuadaryBuiltinPredicate duplicate(jTerm t1,
                                                      jTerm t2,
                                                      jTerm t3,
                                                      jTerm t4)

duplicate

public jTerm duplicate(jVariable[] vars)

Description copied from class: jTerm

Creates a complete and entirely independant duplicate of this term. User should call only for terms for which registerVariables has already been invoked. Within duplicate, any other calls to duplicate should pass along the same vars array produced by registerVariables since the same duplication path previously taken by registerVariables should be taken by duplicate. This call is designed only for terms which belong to rules and are templates for instantiation. Any variables in the term should be unbound. As implied by the modification restrictions on registerVariables, terms and their children cannot change (especially during call!)

Specified by:

duplicate in interface iTerm

Overrides:

duplicate in class jBuiltinPredicate

Parameters:

vars - The user passes in a duplicate of the variable vector produced from the previous call to registerVariables. vars is produced from the jVariableVector by creating a single duplicate variable for each variable. Since this is created in the same order as the registerVariables, it is now efficient for jVariables to return their unique duplicate.

Returns:

jTerm which is an instantiated duplicate of this term.

copy

public jTerm copy(jVariableRegistry vars)

Description copied from class: jTerm

Internal member function which creates a copy of this term. This member function is designed to duplicate a term, but without the restrictions of the duplicate function. Should only be invoked by copy() or other copy(vars). Should only invoke other copy(vars) functions. Bound variables should return a copy of the bound term.

Specified by:

copy in interface iTerm

Overrides:

copy in class jBuiltinPredicate

Parameters:

vars - The registry of variables and their duplicates. Initially this is empty. As variables generate copies, they add themselves and their copy to the jVariableRegistry, and this is output from the function call. Any further calls with the same vars ensures that the same variable (in a different term) returns the same copy.

Returns:

jTerm which is an instantiated copy of this term.

consult

public void consult(jKnowledgeBase kb)

Description copied from interface: iConsultable

Consult the given jKnowledgeBase and cache any invariant values (those which would not change until the next time the jKnowledgeBase changes). Where possible, consultable objects should minimize computation and assume that any cached values are still accurate.

Specified by:

consult in interface iConsultable

Specified by:

consult in interface iTerm

Overrides:

consult in class jTerm

Parameters:

kb - the knowledge base which attempted proofs are based upon.

consultReset

public void consultReset()

Description copied from interface: iConsultable

Called when the jKnowledgeBase changes. Should set all cached values to dirty so that a following call to consult would perform a full lookup as required.

Specified by:

consultReset in interface iConsultable

Specified by:

consultReset in interface iTerm

Overrides:

consultReset in class jTerm

isConsultNeeded

public boolean isConsultNeeded()

Description copied from interface: iConsultable

Determine if cached values already exist and hence if consulting is required. If object does not knowimmediatly whether consulting is needed, then assuming it is required.

Specified by:

isConsultNeeded in interface iConsultable

Specified by:

isConsultNeeded in interface iTerm

Overrides:

isConsultNeeded in class jBuiltinPredicate

Returns:

false if cached values are valid, true otherwise, if consult should be called.

toString

public String toString(boolean usename)

Description copied from class: jTerm

Produces a string identifying this term, suitable for display to the console. param usename determines whether to display variables by name or identity. false is the default for displaying the term, true for displaying this term in a user query.

Specified by:

toString in interface iTerm

Overrides:

toString in class jBuiltinPredicate

Returns:

String which is a textual representation of this term.