it.unibz.inf.ontop.model.term.impl

Class ImmutableFunctionalTermImpl

java.lang.Object

it.unibz.inf.ontop.model.term.impl.ImmutableFunctionalTermImpl

All Implemented Interfaces:

ImmutableFunctionalTerm, ImmutableTerm, NonConstantTerm, NonVariableTerm

Direct Known Subclasses:

GroundFunctionalTermImpl, ImmutableExpressionImpl, NonGroundFunctionalTermImpl

public abstract class ImmutableFunctionalTermImpl
extends Object
implements ImmutableFunctionalTerm

Immutable implementation

Nested Class Summary

Nested classes/interfaces inherited from interface it.unibz.inf.ontop.model.term.ImmutableFunctionalTerm

ImmutableFunctionalTerm.FunctionalTermDecomposition

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ImmutableFunctionalTermImpl(FunctionSymbol functionSymbol, com.google.common.collect.ImmutableList<? extends ImmutableTerm> terms, TermFactory termFactory)
protected	ImmutableFunctionalTermImpl(FunctionSymbol functor, TermFactory termFactory, ImmutableTerm... terms)

Method Summary

Modifier and Type	Method and Description
Optional<ImmutableFunctionalTerm.FunctionalTermDecomposition>	analyzeInjectivity(com.google.common.collect.ImmutableSet<Variable> nonFreeVariables, VariableNullability variableNullability, VariableGenerator variableGenerator) Returns an empty optional when no decomposition is possible In the decomposition, the liftable term is injective.
boolean	canBePostProcessed() Returns true if it can be post-processed modulo some decomposition (i.e.
boolean	equals(Object other) TODO: A bit hacky: only for the functional term that derives from ImmutableFunctionalTermImpl
IncrementalEvaluation	evaluateIsNotNull(VariableNullability variableNullability)
IncrementalEvaluation	evaluateStrictEq(ImmutableTerm otherTerm, VariableNullability variableNullability)
int	getArity()
FunctionSymbol	getFunctionSymbol()
ImmutableTerm	getTerm(int index)
com.google.common.collect.ImmutableList<? extends ImmutableTerm>	getTerms()
com.google.common.collect.ImmutableSet<Variable>	getVariables()
Stream<Variable>	getVariableStream()
int	hashCode()
boolean	isNullable(com.google.common.collect.ImmutableSet<Variable> nullableVariables)
Stream<Variable>	proposeProvenanceVariables() Returns some variables are required to non-null for the functional term to be non-null.
ImmutableTerm	simplify() When no variableNullability is available
ImmutableTerm	simplify(VariableNullability variableNullability)
FunctionalTermSimplification	simplifyAsGuaranteedToBeNonNull() In some occasions, we now that a functional term will never produce a NULL in a given context (e.g.
String	toString() Cached toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface it.unibz.inf.ontop.model.term.ImmutableFunctionalTerm

inferType

Methods inherited from interface it.unibz.inf.ontop.model.term.NonConstantTerm

isNull

Methods inherited from interface it.unibz.inf.ontop.model.term.ImmutableTerm

isGround

Constructor Detail

ImmutableFunctionalTermImpl

protected ImmutableFunctionalTermImpl(FunctionSymbol functor,
                                      TermFactory termFactory,
                                      ImmutableTerm... terms)

ImmutableFunctionalTermImpl

protected ImmutableFunctionalTermImpl(FunctionSymbol functionSymbol,
                                      com.google.common.collect.ImmutableList<? extends ImmutableTerm> terms,
                                      TermFactory termFactory)

Method Detail

getTerm

public ImmutableTerm getTerm(int index)

Specified by:

getTerm in interface ImmutableFunctionalTerm

getFunctionSymbol

public FunctionSymbol getFunctionSymbol()

Specified by:

getFunctionSymbol in interface ImmutableFunctionalTerm

getArity

public int getArity()

Specified by:

getArity in interface ImmutableFunctionalTerm

getTerms

public com.google.common.collect.ImmutableList<? extends ImmutableTerm> getTerms()

Specified by:

getTerms in interface ImmutableFunctionalTerm

getVariables

public com.google.common.collect.ImmutableSet<Variable> getVariables()

Specified by:

getVariables in interface ImmutableFunctionalTerm

getVariableStream

public Stream<Variable> getVariableStream()

Specified by:

getVariableStream in interface ImmutableTerm

toString

public String toString()

Cached toString()

Overrides:

toString in class Object

equals

public boolean equals(Object other)

TODO: A bit hacky: only for the functional term that derives from ImmutableFunctionalTermImpl

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

evaluateStrictEq

public IncrementalEvaluation evaluateStrictEq(ImmutableTerm otherTerm,
                                              VariableNullability variableNullability)

Specified by:

evaluateStrictEq in interface ImmutableTerm

evaluateIsNotNull

public IncrementalEvaluation evaluateIsNotNull(VariableNullability variableNullability)

Specified by:

evaluateIsNotNull in interface ImmutableTerm

simplify

public ImmutableTerm simplify(VariableNullability variableNullability)

Specified by:

simplify in interface ImmutableTerm

simplify

public ImmutableTerm simplify()

Description copied from interface: ImmutableTerm

When no variableNullability is available

Specified by:

simplify in interface ImmutableTerm

analyzeInjectivity

public Optional<ImmutableFunctionalTerm.FunctionalTermDecomposition> analyzeInjectivity(com.google.common.collect.ImmutableSet<Variable> nonFreeVariables,
                                                                                        VariableNullability variableNullability,
                                                                                        VariableGenerator variableGenerator)

Description copied from interface: ImmutableFunctionalTerm

Returns an empty optional when no decomposition is possible In the decomposition, the liftable term is injective.

Specified by:

analyzeInjectivity in interface ImmutableFunctionalTerm

proposeProvenanceVariables

public Stream<Variable> proposeProvenanceVariables()

Description copied from interface: ImmutableFunctionalTerm

Returns some variables are required to non-null for the functional term to be non-null. The stream is NOT guaranteed to be COMPLETE TODO: find a better name

Specified by:

proposeProvenanceVariables in interface ImmutableFunctionalTerm

simplifyAsGuaranteedToBeNonNull

public FunctionalTermSimplification simplifyAsGuaranteedToBeNonNull()

Description copied from interface: ImmutableFunctionalTerm

In some occasions, we now that a functional term will never produce a NULL in a given context (e.g. after applying a filter). This method propagates this information to the functional term as to let it simplify itself. Very useful for NULLIF. For instance "NULLIF(NULLIF(a, 0), 1)" would simplify to "a" as "a" is in the current context guaranteed to be non-null and different from 0 and 1.

Specified by:

simplifyAsGuaranteedToBeNonNull in interface ImmutableFunctionalTerm

canBePostProcessed

public boolean canBePostProcessed()

Description copied from interface: ImmutableFunctionalTerm

Returns true if it can be post-processed modulo some decomposition (i.e. some sub-terms may not post-processed, but the top function symbol yes)

Specified by:

canBePostProcessed in interface ImmutableFunctionalTerm

isNullable

public boolean isNullable(com.google.common.collect.ImmutableSet<Variable> nullableVariables)

Specified by:

isNullable in interface ImmutableTerm