ai.grakn.graql.internal.reasoner.atom.binary

Class Relation

java.lang.Object

ai.grakn.graql.internal.reasoner.atom.AtomicBase

ai.grakn.graql.internal.reasoner.atom.Atom

ai.grakn.graql.internal.reasoner.atom.binary.BinaryBase

ai.grakn.graql.internal.reasoner.atom.binary.Binary

ai.grakn.graql.internal.reasoner.atom.binary.TypeAtom

ai.grakn.graql.internal.reasoner.atom.binary.Relation

All Implemented Interfaces:

Atomic

public class Relation
extends TypeAtom

Atom implementation defining a relation atom corresponding to a combined RelationProperty and (optional) IsaProperty.

Author:

Kasper Piskorski

Field Summary

Fields inherited from class ai.grakn.graql.internal.reasoner.atom.Atom

applicableRules, typeId

Fields inherited from class ai.grakn.graql.internal.reasoner.atom.AtomicBase

atomPattern

Constructor Summary

Constructors

Constructor and Description
Relation(VarPatternAdmin pattern, IdPredicate predicate, ReasonerQuery par)
Relation(Var name, Var typeVariable, Map<Var,VarPattern> roleMap, IdPredicate pred, ReasonerQuery par)

Method Summary

Modifier and Type	Method and Description
Relation	addType(Type type)
int	computePriority(Set<Var> subbedVars) compute resolution priority based on provided substitution variables
Atomic	copy()
boolean	equals(Object obj)
int	equivalenceHashCode()
protected Var	extractValueVariableName(VarPatternAdmin var)
Set<TypeAtom>	getMappedTypeConstraints()
Set<IdPredicate>	getPartialSubstitutions()
Set<Unifier>	getPermutationUnifiers(Atom headAtom)
Set<Var>	getRolePlayers()
com.google.common.collect.Multimap<RoleType,Var>	getRoleVarMap()
Unifier	getUnifier(Atom pAtom) find unifier with parent atom
Set<IdPredicate>	getUnmappedIdPredicates()
Set<Var>	getUnmappedRolePlayers()
Set<TypeAtom>	getUnmappedTypeConstraints()
Set<Var>	getVarNames()
int	hashCode()
List<RelationType>	inferPossibleRelationTypes(Answer sub) infer relation types that this relation atom can potentially have NB: entity types and role types are treated separately as they behave differently: entity types only play the explicitly defined roles (not the relevant part of the hierarchy of the specified role)
void	inferTypes() infers types (type, role types) fo the atom if applicable/possible
boolean	isAllowedToFormRuleHead()
boolean	isEquivalent(Object obj)
boolean	isRelation()
boolean	isRuleApplicable(InferenceRule child)
boolean	isSelectable()
boolean	isType()
boolean	requiresMaterialisation()
Atom	rewriteToUserDefined() rewrites the atom to one with user defined name
protected void	setValueVariable(Var var)
String	toString()

Methods inherited from class ai.grakn.graql.internal.reasoner.atom.binary.TypeAtom

extractTypeId, getType, unify

Methods inherited from class ai.grakn.graql.internal.reasoner.atom.binary.Binary

getCombinedPattern, getPredicate, hasEquivalentPredicatesWith, setParentQuery

Methods inherited from class ai.grakn.graql.internal.reasoner.atom.binary.BinaryBase

getValueVariable

Methods inherited from class ai.grakn.graql.internal.reasoner.atom.Atom

baseResolutionPriority, computePriority, getApplicableRules, getIdPredicates, getNeighbours, getNonSelectableConstraints, getPredicates, getTypeConstraints, getTypeId, getValuePredicates, isAtom, isRecursive, isResource, isRuleResolvable

Methods inherited from class ai.grakn.graql.internal.reasoner.atom.AtomicBase

containsVar, getParentQuery, getPattern, getVarName, graph, isUserDefinedName

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface ai.grakn.graql.admin.Atomic

isPredicate

Constructor Detail

Relation

public Relation(VarPatternAdmin pattern,
                IdPredicate predicate,
                ReasonerQuery par)

Relation

public Relation(Var name,
                Var typeVariable,
                Map<Var,VarPattern> roleMap,
                IdPredicate pred,
                ReasonerQuery par)

Method Detail

toString

public String toString()

Overrides:

toString in class TypeAtom

extractValueVariableName

protected Var extractValueVariableName(VarPatternAdmin var)

Overrides:

extractValueVariableName in class TypeAtom

setValueVariable

protected void setValueVariable(Var var)

Overrides:

setValueVariable in class TypeAtom

copy

public Atomic copy()

Specified by:

copy in interface Atomic

Overrides:

copy in class TypeAtom

equals

public boolean equals(Object obj)

Overrides:

equals in class TypeAtom

hashCode

public int hashCode()

Overrides:

hashCode in class TypeAtom

isEquivalent

public boolean isEquivalent(Object obj)

Specified by:

isEquivalent in interface Atomic

Overrides:

isEquivalent in class BinaryBase

equivalenceHashCode

public int equivalenceHashCode()

Specified by:

equivalenceHashCode in interface Atomic

Overrides:

equivalenceHashCode in class Binary

isRelation

public boolean isRelation()

Overrides:

isRelation in class Atom

Returns:

true if the atom corresponds to a non-unary atom

isSelectable

public boolean isSelectable()

Specified by:

isSelectable in interface Atomic

Overrides:

isSelectable in class TypeAtom

isType

public boolean isType()

Overrides:

isType in class TypeAtom

Returns:

true if the atom corresponds to a atom

requiresMaterialisation

public boolean requiresMaterialisation()

Overrides:

requiresMaterialisation in class TypeAtom

Returns:

true if the atom requires materialisation in order to be referenced

isAllowedToFormRuleHead

public boolean isAllowedToFormRuleHead()

Overrides:

isAllowedToFormRuleHead in class TypeAtom

Returns:

true if the atom can constitute a head of a rule

computePriority

public int computePriority(Set<Var> subbedVars)

Description copied from class: Atom

compute resolution priority based on provided substitution variables

Overrides:

computePriority in class TypeAtom

Parameters:

subbedVars - variables having a substitution

Returns:

resolution priority value

getPartialSubstitutions

public Set<IdPredicate> getPartialSubstitutions()

Overrides:

getPartialSubstitutions in class Atom

Returns:

partial substitutions for this atom (NB: instances)

isRuleApplicable

public boolean isRuleApplicable(InferenceRule child)

Overrides:

isRuleApplicable in class TypeAtom

addType

public Relation addType(Type type)

inferPossibleRelationTypes

public List<RelationType> inferPossibleRelationTypes(Answer sub)

infer relation types that this relation atom can potentially have NB: entity types and role types are treated separately as they behave differently: entity types only play the explicitly defined roles (not the relevant part of the hierarchy of the specified role)

Returns:

list of relation types this atom can have ordered by the number of compatible role types

inferTypes

public void inferTypes()

Description copied from class: Atom

infers types (type, role types) fo the atom if applicable/possible

Overrides:

inferTypes in class Atom

getVarNames

public Set<Var> getVarNames()

Specified by:

getVarNames in interface Atomic

Overrides:

getVarNames in class BinaryBase

getRolePlayers

public Set<Var> getRolePlayers()

Returns:

set constituting the role player var names

getUnmappedRolePlayers

public Set<Var> getUnmappedRolePlayers()

Returns:

set constituting the role player var names that do not have a specified role type

getUnmappedIdPredicates

public Set<IdPredicate> getUnmappedIdPredicates()

Overrides:

getUnmappedIdPredicates in class Atom

getMappedTypeConstraints

public Set<TypeAtom> getMappedTypeConstraints()

Overrides:

getMappedTypeConstraints in class Atom

getUnmappedTypeConstraints

public Set<TypeAtom> getUnmappedTypeConstraints()

Overrides:

getUnmappedTypeConstraints in class Atom

getPermutationUnifiers

public Set<Unifier> getPermutationUnifiers(Atom headAtom)

Overrides:

getPermutationUnifiers in class Atom

getRoleVarMap

public com.google.common.collect.Multimap<RoleType,Var> getRoleVarMap()

getUnifier

public Unifier getUnifier(Atom pAtom)

Description copied from class: Atom

find unifier with parent atom

Overrides:

getUnifier in class BinaryBase

Parameters:

pAtom - atom to be unified with

Returns:

unifier

rewriteToUserDefined

public Atom rewriteToUserDefined()

Description copied from class: Atom

rewrites the atom to one with user defined name

Overrides:

rewriteToUserDefined in class Atom

Returns:

pair of (rewritten atom, unifiers required to unify child with rewritten atom)