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

Class MinOrMaxSPARQLFunctionSymbolImpl

java.lang.Object

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

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

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

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

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

All Implemented Interfaces:

AggregationFunctionSymbol, FunctionSymbol, Predicate, SPARQLAggregationFunctionSymbol, SPARQLFunctionSymbol

Direct Known Subclasses:

MinBasedSampleSPARQLFunctionSymbol

public class MinOrMaxSPARQLFunctionSymbolImpl
extends SPARQLFunctionSymbolImpl
implements SPARQLAggregationFunctionSymbol

Nested Class Summary

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

SPARQLAggregationFunctionSymbol.AggregationSimplification

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

FunctionSymbol.FunctionalTermNullability

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	MinOrMaxSPARQLFunctionSymbolImpl(String name, String officialName, TypeFactory typeFactory, boolean isMax)
protected	MinOrMaxSPARQLFunctionSymbolImpl(TypeFactory typeFactory, boolean isMax)

Method Summary

Modifier and Type	Method and Description
boolean	canBePostProcessed(com.google.common.collect.ImmutableList<? extends ImmutableTerm> arguments) 1.
Optional<SPARQLAggregationFunctionSymbol.AggregationSimplification>	decomposeIntoDBAggregation(com.google.common.collect.ImmutableList<? extends ImmutableTerm> subTerms, com.google.common.collect.ImmutableList<com.google.common.collect.ImmutableSet<RDFTermType>> possibleRDFTypes, boolean hasGroupBy, VariableNullability variableNullability, VariableGenerator variableGenerator, TermFactory termFactory) TODO: put it into common in an abstract class
Constant	evaluateEmptyBag(TermFactory termFactory)
Optional<TermTypeInference>	inferType(com.google.common.collect.ImmutableList<? extends ImmutableTerm> terms) Too complex to be implemented for the moment
boolean	isAggregation() By default, assume it is not an aggregation function symbol To be overridden when needed
boolean	isAlwaysInjectiveInTheAbsenceOfNonInjectiveFunctionalTerms() When the function symbol is, in the absence of non-injective functional sub-terms, sometimes but not always injective, please override isInjective(...)
boolean	isNullable(com.google.common.collect.ImmutableSet<Integer> nullableIndexes) By default, to be overridden by function symbols that supports tolerate NULL values
protected boolean	tolerateNulls() Returns true if is not guaranteed to return NULL when one argument is NULL.

Methods inherited from class it.unibz.inf.ontop.model.term.functionsymbol.impl.SPARQLFunctionSymbolImpl

getIRI, getOfficialName

Methods inherited from class it.unibz.inf.ontop.model.term.functionsymbol.impl.SPARQLLikeFunctionSymbolImpl

extractLexicalTerm, extractRDFTermTypeTerm, isRDFFunctionalTerm, mayReturnNullWithoutNullArguments

Methods inherited from class it.unibz.inf.ontop.model.term.functionsymbol.impl.FunctionSymbolImpl

analyzeInjectivity, buildTermAfterEvaluation, canBeSafelyDecomposedIntoConjunction, decomposeInjectiveTopFunctionalTerm, enableIfElseNullLifting, evaluateIsNotNull, evaluateNullability, evaluateStrictEq, evaluateStrictEqWithFunctionalTerm, evaluateStrictEqWithNonNullConstant, getExpectedBaseType, getExpectedBaseTypes, isDeterministic, isInjective, proposeProvenanceVariables, simplify, simplifyAsGuaranteedToBeNonNull, transformIntoRegularArguments, tryToLiftMagicNumbers

Methods inherited from class it.unibz.inf.ontop.model.term.impl.PredicateImpl

equals, getArity, getName, hashCode, 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.functionsymbol.SPARQLFunctionSymbol

getIRI, getOfficialName

Methods inherited from interface it.unibz.inf.ontop.model.term.functionsymbol.FunctionSymbol

analyzeInjectivity, evaluateIsNotNull, evaluateNullability, evaluateStrictEq, getExpectedBaseType, isDeterministic, proposeProvenanceVariables, simplify, simplifyAsGuaranteedToBeNonNull

Methods inherited from interface it.unibz.inf.ontop.model.term.functionsymbol.Predicate

getArity, getName

Constructor Detail

MinOrMaxSPARQLFunctionSymbolImpl

protected MinOrMaxSPARQLFunctionSymbolImpl(TypeFactory typeFactory,
                                           boolean isMax)

MinOrMaxSPARQLFunctionSymbolImpl

protected MinOrMaxSPARQLFunctionSymbolImpl(String name,
                                           String officialName,
                                           TypeFactory typeFactory,
                                           boolean isMax)

Method Detail

tolerateNulls

protected boolean tolerateNulls()

Description copied from class: FunctionSymbolImpl

Returns true if is not guaranteed to return NULL when one argument is NULL. Can be the case for some function symbols that are rejecting certain cases and therefore refuse to simplify themselves, e.g. RDF(NULL,IRI) is invalid and therefore cannot be simplified.

Specified by:

tolerateNulls in class FunctionSymbolImpl

isAlwaysInjectiveInTheAbsenceOfNonInjectiveFunctionalTerms

public boolean isAlwaysInjectiveInTheAbsenceOfNonInjectiveFunctionalTerms()

Description copied from class: FunctionSymbolImpl

When the function symbol is, in the absence of non-injective functional sub-terms, sometimes but not always injective, please override isInjective(...)

Specified by:

isAlwaysInjectiveInTheAbsenceOfNonInjectiveFunctionalTerms in class FunctionSymbolImpl

isAggregation

public boolean isAggregation()

Description copied from class: FunctionSymbolImpl

By default, assume it is not an aggregation function symbol To be overridden when needed

Specified by:

isAggregation in interface FunctionSymbol

Overrides:

isAggregation in class FunctionSymbolImpl

inferType

public Optional<TermTypeInference> inferType(com.google.common.collect.ImmutableList<? extends ImmutableTerm> terms)

Too complex to be implemented for the moment

Specified by:

inferType in interface FunctionSymbol

canBePostProcessed

public boolean canBePostProcessed(com.google.common.collect.ImmutableList<? extends ImmutableTerm> arguments)

Description copied from interface: FunctionSymbol

1. When a functional term simplifies itself in a BOTTOM-UP manner: Returns true if is guaranteed to "simplify itself" as a Constant when receiving Constants as arguments (outside the optimization phase) . 2. When a functional term simplifies itself in a TOP-DOWN manner (e.g. IF-THEN-ELSE functional terms): The permission for post-processing may depend on the ability of sub-functional terms to be post-processed or safely evaluated by the DB engine. (Recall that top-down evaluation allows some arguments not to be evaluated when their pre-conditions are not met. This is particularly valuable for preventing fatal errors).

Specified by:

canBePostProcessed in interface FunctionSymbol

isNullable

public boolean isNullable(com.google.common.collect.ImmutableSet<Integer> nullableIndexes)

Description copied from class: FunctionSymbolImpl

By default, to be overridden by function symbols that supports tolerate NULL values

Specified by:

isNullable in interface FunctionSymbol

Overrides:

isNullable in class FunctionSymbolImpl

decomposeIntoDBAggregation

public Optional<SPARQLAggregationFunctionSymbol.AggregationSimplification> decomposeIntoDBAggregation(com.google.common.collect.ImmutableList<? extends ImmutableTerm> subTerms,
                                                                                                      com.google.common.collect.ImmutableList<com.google.common.collect.ImmutableSet<RDFTermType>> possibleRDFTypes,
                                                                                                      boolean hasGroupBy,
                                                                                                      VariableNullability variableNullability,
                                                                                                      VariableGenerator variableGenerator,
                                                                                                      TermFactory termFactory)

TODO: put it into common in an abstract class

Specified by:

decomposeIntoDBAggregation in interface SPARQLAggregationFunctionSymbol

evaluateEmptyBag

public Constant evaluateEmptyBag(TermFactory termFactory)

Specified by:

evaluateEmptyBag in interface AggregationFunctionSymbol