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

Class AbstractDBIfThenFunctionSymbol

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.db.impl.AbstractArgDependentTypedDBFunctionSymbol

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

All Implemented Interfaces:

DBFunctionSymbol, DBFunctionSymbolSerializer, DBIfThenFunctionSymbol, FunctionSymbol, Predicate

Direct Known Subclasses:

AbstractDBIfThenElseFunctionSymbol, DefaultDBCaseFunctionSymbol, DefaultDBIfElseNullFunctionSymbol

public abstract class AbstractDBIfThenFunctionSymbol
extends AbstractArgDependentTypedDBFunctionSymbol
implements DBIfThenFunctionSymbol

Abstract both for IF-THEN-ELSE or more general CASE Arguments are an alternation of (ImmutableExpression, ImmutableTerm) plus optionally an ImmutableTerm for the default case

Nested Class Summary

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

FunctionSymbol.FunctionalTermNullability

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	doOrderingMatter

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractDBIfThenFunctionSymbol(String name, int arity, DBTermType dbBooleanType, DBTermType rootDBTermType, boolean doOrderingMatter)

Method Summary

Modifier and Type	Method and Description
protected ImmutableFunctionalTerm	buildCase(Stream<Map.Entry<ImmutableExpression,? extends ImmutableTerm>> newWhenPairs, ImmutableTerm defaultValue, TermFactory termFactory) Can be overridden
boolean	canBePostProcessed(com.google.common.collect.ImmutableList<? extends ImmutableTerm> arguments) Conservative: can only be post-processed when all sub-functional terms (at different levels of depth) can be post-processed.
protected abstract ImmutableTerm	extractDefaultValue(com.google.common.collect.ImmutableList<? extends ImmutableTerm> terms, TermFactory termFactory)
Stream<ImmutableTerm>	extractPossibleValues(com.google.common.collect.ImmutableList<? extends ImmutableTerm> terms)
protected Stream<ImmutableFunctionalTerm>	extractSubFunctionalTerms(com.google.common.collect.ImmutableList<? extends ImmutableTerm> subTerms) Recursive
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	isPreferringToBePostProcessedOverBeingBlocked() If it is better to be post-processed than being blocked behind an UNION.
protected boolean	mayReturnNullWithoutNullArguments() Default, can be overridden
ImmutableExpression	pushDownExpression(ImmutableExpression expression, int indexOfDBIfThenFunctionSymbol, TermFactory termFactory) Pushes a unary boolean function symbol down to the "then" arguments For instance, f(CASE(c1, t1, c2, t2, t3), t4) -> BOOL_CASE(c1, f(t1,t4), c2, f(t2,t4), f(t3,t4))
protected <T extends ImmutableFunctionalTerm> T	pushDownFunctionalTerm(T functionalTerm, int indexOfDBIfThenFunctionSymbol, TermFactory termFactory, BiFunction<FunctionSymbol,com.google.common.collect.ImmutableList<? extends ImmutableTerm>,T> functionalTermCst, BiFunction<Stream<Map.Entry<ImmutableExpression,T>>,T,T> caseCst)
ImmutableFunctionalTerm	pushDownRegularFunctionalTerm(ImmutableFunctionalTerm functionalTerm, int indexOfDBIfThenFunctionSymbol, TermFactory termFactory) Similar to pushDownExpression(...) but for regular functional terms
ImmutableTerm	simplify(com.google.common.collect.ImmutableList<? extends ImmutableTerm> terms, TermFactory termFactory, VariableNullability variableNullability)
protected ImmutableTerm	simplifyValue(ImmutableTerm immutableTerm, VariableNullability variableNullability, TermFactory termFactory) Can be overridden
protected boolean	tolerateNulls() Returns true if is not guaranteed to return NULL when one argument is NULL.
protected com.google.common.collect.ImmutableList<? extends ImmutableTerm>	transformIntoRegularArguments(com.google.common.collect.ImmutableList<? extends NonFunctionalTerm> arguments, TermFactory termFactory) Requires some of its arguments to be expressions

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

inferType

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, isAggregation, isDeterministic, isInjective, isNullable, proposeProvenanceVariables, simplifyAsGuaranteedToBeNonNull, 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.FunctionSymbol

analyzeInjectivity, evaluateIsNotNull, evaluateNullability, evaluateStrictEq, getExpectedBaseType, inferType, isAggregation, isDeterministic, isNullable, proposeProvenanceVariables, simplifyAsGuaranteedToBeNonNull

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

getArity, getName

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

getNativeDBString

Field Detail

doOrderingMatter

protected final boolean doOrderingMatter

Constructor Detail

AbstractDBIfThenFunctionSymbol

protected AbstractDBIfThenFunctionSymbol(@Nonnull
                                         String name,
                                         int arity,
                                         DBTermType dbBooleanType,
                                         DBTermType rootDBTermType,
                                         boolean doOrderingMatter)

Method Detail

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

extractPossibleValues

public Stream<ImmutableTerm> extractPossibleValues(com.google.common.collect.ImmutableList<? extends ImmutableTerm> terms)

Specified by:

extractPossibleValues in interface DBIfThenFunctionSymbol

Specified by:

extractPossibleValues in class AbstractArgDependentTypedDBFunctionSymbol

simplify

public ImmutableTerm simplify(com.google.common.collect.ImmutableList<? extends ImmutableTerm> terms,
                              TermFactory termFactory,
                              VariableNullability variableNullability)

Specified by:

simplify in interface FunctionSymbol

Overrides:

simplify in class FunctionSymbolImpl

simplifyValue

protected ImmutableTerm simplifyValue(ImmutableTerm immutableTerm,
                                      VariableNullability variableNullability,
                                      TermFactory termFactory)

Can be overridden

buildCase

protected ImmutableFunctionalTerm buildCase(Stream<Map.Entry<ImmutableExpression,? extends ImmutableTerm>> newWhenPairs,
                                            ImmutableTerm defaultValue,
                                            TermFactory termFactory)

Can be overridden

canBePostProcessed

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

Conservative: can only be post-processed when all sub-functional terms (at different levels of depth) can be post-processed. TODO: consider perhaps a less conservative approach

Specified by:

canBePostProcessed in interface FunctionSymbol

extractSubFunctionalTerms

protected Stream<ImmutableFunctionalTerm> extractSubFunctionalTerms(com.google.common.collect.ImmutableList<? extends ImmutableTerm> subTerms)

Recursive

extractDefaultValue

protected abstract ImmutableTerm extractDefaultValue(com.google.common.collect.ImmutableList<? extends ImmutableTerm> terms,
                                                     TermFactory termFactory)

mayReturnNullWithoutNullArguments

protected boolean mayReturnNullWithoutNullArguments()

Default, can be overridden

Specified by:

mayReturnNullWithoutNullArguments in class FunctionSymbolImpl

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

isPreferringToBePostProcessedOverBeingBlocked

public boolean isPreferringToBePostProcessedOverBeingBlocked()

Description copied from interface: DBFunctionSymbol

If it is better to be post-processed than being blocked behind an UNION. Obviously, non post-processable function symbols must return false.

Specified by:

isPreferringToBePostProcessedOverBeingBlocked in interface DBFunctionSymbol

transformIntoRegularArguments

protected com.google.common.collect.ImmutableList<? extends ImmutableTerm> transformIntoRegularArguments(com.google.common.collect.ImmutableList<? extends NonFunctionalTerm> arguments,
                                                                                                         TermFactory termFactory)

Requires some of its arguments to be expressions

Overrides:

transformIntoRegularArguments in class FunctionSymbolImpl

pushDownExpression

public ImmutableExpression pushDownExpression(ImmutableExpression expression,
                                              int indexOfDBIfThenFunctionSymbol,
                                              TermFactory termFactory)

Description copied from interface: DBIfThenFunctionSymbol

Pushes a unary boolean function symbol down to the "then" arguments For instance, f(CASE(c1, t1, c2, t2, t3), t4) -> BOOL_CASE(c1, f(t1,t4), c2, f(t2,t4), f(t3,t4))

Specified by:

pushDownExpression in interface DBIfThenFunctionSymbol

pushDownRegularFunctionalTerm

public ImmutableFunctionalTerm pushDownRegularFunctionalTerm(ImmutableFunctionalTerm functionalTerm,
                                                             int indexOfDBIfThenFunctionSymbol,
                                                             TermFactory termFactory)

Description copied from interface: DBIfThenFunctionSymbol

Similar to pushDownExpression(...) but for regular functional terms

Specified by:

pushDownRegularFunctionalTerm in interface DBIfThenFunctionSymbol

pushDownFunctionalTerm

protected <T extends ImmutableFunctionalTerm> T pushDownFunctionalTerm(T functionalTerm,
                                                                       int indexOfDBIfThenFunctionSymbol,
                                                                       TermFactory termFactory,
                                                                       BiFunction<FunctionSymbol,com.google.common.collect.ImmutableList<? extends ImmutableTerm>,T> functionalTermCst,
                                                                       BiFunction<Stream<Map.Entry<ImmutableExpression,T>>,T,T> caseCst)