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

Class RelationshipAtom

java.lang.Object

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

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

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

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

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

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

All Implemented Interfaces:

Atomic

public class RelationshipAtom
extends IsaAtom

Atom implementation defining a relation atom corresponding to a combined RelationshipProperty and (optional) IsaProperty. The relation atom is a TypeAtom with relationship players.

Author:

Kasper Piskorski

Constructor Summary

Constructors

Constructor and Description
RelationshipAtom(VarPatternAdmin pattern, Var predicateVar, IdPredicate predicate, ReasonerQuery par)

Method Summary

Modifier and Type	Method and Description
RelationshipAtom	addType(SchemaConcept type)
List<Atom>	atomOptions(Answer sub)
int	computePriority(Set<Var> subbedVars) compute resolution priority based on provided substitution variables
Atomic	copy()
boolean	equals(Object obj)
int	equivalenceHashCode()
java.util.stream.Stream<Predicate>	getInnerPredicates()
MultiUnifier	getMultiUnifier(Atom pAtom, boolean exact) find the (multi) unifier with parent atom
java.util.stream.Stream<IdPredicate>	getPartialSubstitutions()
Set<Var>	getRoleExpansionVariables()
Set<Var>	getRolePlayers()
java.util.stream.Stream<IdPredicate>	getRolePredicates()
com.google.common.collect.Multimap<Role,Var>	getRoleVarMap()
Set<TypeAtom>	getSpecificTypeConstraints()
Unifier	getUnifier(Atom pAtom)
Set<Var>	getVarNames()
int	hashCode()
com.google.common.collect.ImmutableList<RelationshipType>	inferPossibleRelationTypes(Answer sub) infer RelationshipTypes that this RelationshipAtom can potentially have NB: EntityTypes and link Roles are treated separately as they behave differently: EntityTypes only play the explicitly defined Roles (not the relevant part of the hierarchy of the specified Role) and the Role inherited from parent
RelationshipAtom	inferTypes()
boolean	isAllowedToFormRuleHead()
boolean	isEquivalent(Object obj)
boolean	isRelation()
boolean	isRuleApplicableViaAtom(Atom ruleAtom)
boolean	isSelectable()
boolean	isType()
boolean	requiresMaterialisation()
boolean	requiresRoleExpansion()
Atom	rewriteToUserDefined(Atom parentAtom) rewrites the atom to one with user defined name
RelationshipAtom	toRelationshipAtom()
String	toString()
Set<String>	validateOntologically()

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

getTypedPair, unify

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

getSchemaConcept

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

getCombinedPattern, getPredicateVariable, getTypeId, getTypePredicate, setParentQuery

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

baseResolutionPriority, getApplicableRules, getIdPredicate, getInnerPredicates, getNeighbours, getNonSelectableConstraints, getPredicate, getPredicates, getPredicates, getTypeConstraints, getVarProperties, isAtom, isRecursive, isRuleResolvable

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

containsVar, getParentQuery, getPattern, getVarName, isUserDefined, tx

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, isResource

Constructor Detail

RelationshipAtom

public RelationshipAtom(VarPatternAdmin pattern,
                        Var predicateVar,
                        @Nullable
                        IdPredicate predicate,
                        ReasonerQuery par)

Method Detail

toRelationshipAtom

public RelationshipAtom toRelationshipAtom()

Overrides:

toRelationshipAtom in class Atom

toString

public String toString()

Overrides:

toString in class IsaAtom

getRolePlayers

public Set<Var> getRolePlayers()

Returns:

set constituting the role player var names

copy

public Atomic copy()

Specified by:

copy in interface Atomic

Overrides:

copy in class IsaAtom

hashCode

public int hashCode()

Overrides:

hashCode in class TypeAtom

equals

public boolean equals(Object obj)

Overrides:

equals in class TypeAtom

isEquivalent

public boolean isEquivalent(Object obj)

Specified by:

isEquivalent in interface Atomic

Overrides:

isEquivalent in class Binary

equivalenceHashCode

public int equivalenceHashCode()

Specified by:

equivalenceHashCode in interface Atomic

Overrides:

equivalenceHashCode in class Binary

isRelation

public boolean isRelation()

isSelectable

public boolean isSelectable()

Specified by:

isSelectable in interface Atomic

Overrides:

isSelectable in class TypeAtom

isType

public boolean isType()

Specified by:

isType in interface Atomic

Overrides:

isType in class TypeAtom

requiresMaterialisation

public boolean requiresMaterialisation()

Overrides:

requiresMaterialisation in class TypeAtom

Returns:

true if the atom requires materialisation in order to be referenced

requiresRoleExpansion

public boolean requiresRoleExpansion()

Overrides:

requiresRoleExpansion in class Atom

Returns:

true if the atom requires role expansion

isAllowedToFormRuleHead

public boolean isAllowedToFormRuleHead()

Specified by:

isAllowedToFormRuleHead in interface Atomic

Overrides:

isAllowedToFormRuleHead in class IsaAtom

validateOntologically

public Set<String> validateOntologically()

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 java.util.stream.Stream<IdPredicate> getPartialSubstitutions()

Overrides:

getPartialSubstitutions in class Atom

Returns:

partial substitutions for this atom (NB: instances)

getRolePredicates

public java.util.stream.Stream<IdPredicate> getRolePredicates()

isRuleApplicableViaAtom

public boolean isRuleApplicableViaAtom(Atom ruleAtom)

Overrides:

isRuleApplicableViaAtom in class TypeAtom

addType

public RelationshipAtom addType(SchemaConcept type)

Overrides:

addType in class IsaAtom

Parameters:

type - to be added to this Atom

Returns:

new Atom with specified type

inferPossibleRelationTypes

public com.google.common.collect.ImmutableList<RelationshipType> inferPossibleRelationTypes(Answer sub)

infer RelationshipTypes that this RelationshipAtom can potentially have NB: EntityTypes and link Roles are treated separately as they behave differently: EntityTypes only play the explicitly defined Roles (not the relevant part of the hierarchy of the specified Role) and the Role inherited from parent

Returns:

list of RelationshipTypes this atom can have ordered by the number of compatible Roles

inferTypes

public RelationshipAtom inferTypes()

Specified by:

inferTypes in interface Atomic

Overrides:

inferTypes in class Atom

atomOptions

public List<Atom> atomOptions(Answer sub)

Overrides:

atomOptions in class Atom

Parameters:

sub - partial substitution

Returns:

list of possible atoms obtained by applying type inference

getVarNames

public Set<Var> getVarNames()

Specified by:

getVarNames in interface Atomic

Overrides:

getVarNames in class Binary

getRoleExpansionVariables

public Set<Var> getRoleExpansionVariables()

Overrides:

getRoleExpansionVariables in class Atom

Returns:

set of variables that need to be have their roles expanded

getSpecificTypeConstraints

public Set<TypeAtom> getSpecificTypeConstraints()

Overrides:

getSpecificTypeConstraints in class Atom

Returns:

set of type atoms that describe specific role players or resource owner

getInnerPredicates

public java.util.stream.Stream<Predicate> getInnerPredicates()

Overrides:

getInnerPredicates in class Binary

getRoleVarMap

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

Returns:

map containing roleType - (rolePlayer var - rolePlayer type) pairs

getUnifier

public Unifier getUnifier(Atom pAtom)

Overrides:

getUnifier in class Binary

Parameters:

pAtom - atom to be unified with

Returns:

corresponding unifier

getMultiUnifier

public MultiUnifier getMultiUnifier(Atom pAtom,
                                    boolean exact)

Description copied from class: Atom

find the (multi) unifier with parent atom

Overrides:

getMultiUnifier in class Atom

Parameters:

pAtom - atom to be unified with

exact - flag indicating whether unification should be exact

Returns:

multiunifier

rewriteToUserDefined

public Atom rewriteToUserDefined(Atom parentAtom)

Description copied from class: Atom

rewrites the atom to one with user defined name

Overrides:

rewriteToUserDefined in class Atom

Parameters:

parentAtom - parent atom that triggers rewrite

Returns:

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