it.unibz.inf.ontop.iq.node

Interface VariableNullability

All Known Implementing Classes:

VariableNullabilityImpl

public interface VariableNullability

TODO: find a better name IMMUTABLE See CoreUtilsFactory for creating new instances

Method Summary

Modifier and Type	Method and Description
VariableNullability	applyFreshRenaming(InjectiveVar2VarSubstitution freshRenamingSubstitution)
boolean	canPossiblyBeNullSeparately(it.unibz.inf.ontop.com.google.common.collect.ImmutableList<? extends ImmutableTerm> terms) Generalization to arbitrary terms
boolean	canPossiblyBeNullSeparately(it.unibz.inf.ontop.com.google.common.collect.ImmutableSet<Variable> variables) Returns true if it possible that among the variables at least two can be null but are not required to be null at the same time.
VariableNullability	extendToExternalVariables(Stream<Variable> possiblyExternalVariables) Returns a new VariableNullability.
it.unibz.inf.ontop.com.google.common.collect.ImmutableSet<it.unibz.inf.ontop.com.google.common.collect.ImmutableSet<Variable>>	getNullableGroups() All the variables of a group are always null at the same time (guaranteed).
default it.unibz.inf.ontop.com.google.common.collect.ImmutableSet<Variable>	getNullableVariables()
boolean	isPossiblyNullable(Variable variable) NB: for variables outside its scope, returns true (as it does not know anything about them) TODO: stop tolerating variables outside its scope and throw an exception if it happens (inconsistent with nullable groups)!
VariableNullability	update(ImmutableSubstitution<? extends ImmutableTerm> substitution, it.unibz.inf.ontop.com.google.common.collect.ImmutableSet<Variable> projectedVariables)

Method Detail

isPossiblyNullable

boolean isPossiblyNullable(Variable variable)

NB: for variables outside its scope, returns true (as it does not know anything about them) TODO: stop tolerating variables outside its scope and throw an exception if it happens (inconsistent with nullable groups)!

canPossiblyBeNullSeparately

boolean canPossiblyBeNullSeparately(it.unibz.inf.ontop.com.google.common.collect.ImmutableSet<Variable> variables)

Returns true if it possible that among the variables at least two can be null but are not required to be null at the same time.

canPossiblyBeNullSeparately

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

Generalization to arbitrary terms

getNullableGroups

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

All the variables of a group are always null at the same time (guaranteed).

update

VariableNullability update(ImmutableSubstitution<? extends ImmutableTerm> substitution,
                           it.unibz.inf.ontop.com.google.common.collect.ImmutableSet<Variable> projectedVariables)

applyFreshRenaming

VariableNullability applyFreshRenaming(InjectiveVar2VarSubstitution freshRenamingSubstitution)

extendToExternalVariables

VariableNullability extendToExternalVariables(Stream<Variable> possiblyExternalVariables)

Returns a new VariableNullability. Treats the external variables (outside the scope) as independently nullable.

getNullableVariables

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