it.unibz.inf.ontop.model.term

Interface ImmutableFunctionalTerm

All Superinterfaces:

ImmutableTerm, NonConstantTerm, NonVariableTerm

All Known Subinterfaces:

GroundFunctionalTerm, ImmutableExpression, NonGroundFunctionalTerm

All Known Implementing Classes:

GroundExpressionImpl, GroundFunctionalTermImpl, ImmutableExpressionImpl, ImmutableFunctionalTermImpl, NonGroundExpressionImpl, NonGroundFunctionalTermImpl

public interface ImmutableFunctionalTerm
extends NonVariableTerm, NonConstantTerm

Functional term that is declared as immutable.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	ImmutableFunctionalTerm.FunctionalTermDecomposition

Method Summary

Modifier and Type	Method and Description
Optional<ImmutableFunctionalTerm.FunctionalTermDecomposition>	analyzeInjectivity(it.unibz.inf.ontop.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.
int	getArity()
FunctionSymbol	getFunctionSymbol()
ImmutableTerm	getTerm(int index)
it.unibz.inf.ontop.com.google.common.collect.ImmutableList<? extends ImmutableTerm>	getTerms()
it.unibz.inf.ontop.com.google.common.collect.ImmutableSet<Variable>	getVariables()
default Optional<TermTypeInference>	inferType() Returns empty when no TermType has been inferred (missing information or fatal error) and no non-fatal error has been detected.
Stream<Variable>	proposeProvenanceVariables() Returns some variables are required to non-null for the functional term to be non-null.
FunctionalTermSimplification	simplifyAsGuaranteedToBeNonNull() In some occasions, we now that a functional term will never produce a NULL in a given context (e.g.

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

isNull

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

evaluateIsNotNull, evaluateStrictEq, getVariableStream, isGround, isNullable, simplify, simplify

Method Detail

getTerms

it.unibz.inf.ontop.com.google.common.collect.ImmutableList<? extends ImmutableTerm> getTerms()

getTerm

ImmutableTerm getTerm(int index)

getFunctionSymbol

FunctionSymbol getFunctionSymbol()

getArity

int getArity()

getVariables

it.unibz.inf.ontop.com.google.common.collect.ImmutableSet<Variable> getVariables()

inferType

default Optional<TermTypeInference> inferType()

Description copied from interface: ImmutableTerm

Returns empty when no TermType has been inferred (missing information or fatal error) and no non-fatal error has been detected.

Specified by:

inferType in interface ImmutableTerm

canBePostProcessed

boolean canBePostProcessed()

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)

analyzeInjectivity

Optional<ImmutableFunctionalTerm.FunctionalTermDecomposition> analyzeInjectivity(it.unibz.inf.ontop.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.

proposeProvenanceVariables

Stream<Variable> proposeProvenanceVariables()

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

simplifyAsGuaranteedToBeNonNull

FunctionalTermSimplification simplifyAsGuaranteedToBeNonNull()

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.