it.unibz.inf.ontop.iq.node.impl

Class LeftJoinNodeImpl

java.lang.Object

it.unibz.inf.ontop.iq.node.impl.QueryNodeImpl

it.unibz.inf.ontop.iq.node.impl.CompositeQueryNodeImpl

it.unibz.inf.ontop.iq.node.impl.JoinOrFilterNodeImpl

it.unibz.inf.ontop.iq.node.impl.JoinLikeNodeImpl

it.unibz.inf.ontop.iq.node.impl.LeftJoinNodeImpl

All Implemented Interfaces:

BinaryNonCommutativeOperatorNode, BinaryOrderedOperatorNode, JoinLikeNode, JoinOrFilterNode, LeftJoinNode, QueryNode, Cloneable

public class LeftJoinNodeImpl
extends JoinLikeNodeImpl
implements LeftJoinNode

Nested Class Summary

Nested classes/interfaces inherited from interface it.unibz.inf.ontop.iq.node.BinaryOrderedOperatorNode

BinaryOrderedOperatorNode.ArgumentPosition

Field Summary

Fields inherited from class it.unibz.inf.ontop.iq.node.impl.JoinOrFilterNodeImpl

substitutionFactory, substitutionTools, termFactory, typeFactory, unificationTools

Method Summary

Modifier and Type	Method and Description
LeftJoinNode	acceptNodeTransformer(HomogeneousQueryNodeTransformer transformer) "Accept" method for the "Visitor" pattern.
IQTree	acceptTransformer(IQTree tree, IQTreeVisitingTransformer transformer, IQTree leftChild, IQTree rightChild)
<T> T	acceptVisitor(IQVisitor<T> visitor, IQTree leftChild, IQTree rightChild)
void	acceptVisitor(QueryNodeVisitor visitor) "Accept" method for the "Visitor" pattern.
IQTree	applyDescendingSubstitution(ImmutableSubstitution<? extends VariableOrGroundTerm> descendingSubstitution, Optional<ImmutableExpression> constraint, IQTree leftChild, IQTree rightChild) NB: the constraint is only propagate to the left child
IQTree	applyDescendingSubstitutionWithoutOptimizing(ImmutableSubstitution<? extends VariableOrGroundTerm> descendingSubstitution, IQTree leftChild, IQTree rightChild)
IQTree	applyFreshRenaming(InjectiveVar2VarSubstitution renamingSubstitution, IQTree leftChild, IQTree rightChild, IQTreeCache treeCache)
LeftJoinNode	changeOptionalFilterCondition(Optional<ImmutableExpression> newOptionalFilterCondition) Constructs a new JoinLikeNode with the following optional filter condition (recall that a QueryNode is immutable).
LeftJoinNode	clone() See https://stackoverflow.com/questions/6837362/
com.google.common.collect.ImmutableSet<ImmutableSubstitution<NonVariableTerm>>	getPossibleVariableDefinitions(IQTree leftChild, IQTree rightChild) Returns possible definitions for left and right-specific variables.
VariableNullability	getVariableNullability(IQTree leftChild, IQTree rightChild) Variable nullability for the full LJ tree
com.google.common.collect.ImmutableSet<com.google.common.collect.ImmutableSet<Variable>>	inferUniqueConstraints(IQTree leftChild, IQTree rightChild) TODO: implement it seriously
boolean	isConstructed(Variable variable, IQTree leftChild, IQTree rightChild)
boolean	isDistinct(IQTree leftChild, IQTree rightChild)
boolean	isEquivalentTo(QueryNode queryNode) Is syntactically equivalent
boolean	isSyntacticallyEquivalentTo(QueryNode node) TODO: explain
boolean	isVariableNullable(IntermediateQuery query, Variable variable) Returns true if it cannot guarantee the projected variable to be non-null Throws an IllegalArgumentException if the variable is not projected by the node
IQTree	liftIncompatibleDefinitions(Variable variable, IQTree leftChild, IQTree rightChild, VariableGenerator variableGenerator)
IQTree	normalizeForOptimization(IQTree initialLeftChild, IQTree initialRightChild, VariableGenerator variableGenerator, IQProperties currentIQProperties)
IQTree	propagateDownConstraint(ImmutableExpression constraint, IQTree leftChild, IQTree rightChild)
IQTree	removeDistincts(IQTree leftChild, IQTree rightChild, IQProperties properties)
String	toString()
void	validateNode(IQTree leftChild, IQTree rightChild) Only validates the node, not its children

Methods inherited from class it.unibz.inf.ontop.iq.node.impl.JoinLikeNodeImpl

checkNonProjectedVariables, getRequiredVariables

Methods inherited from class it.unibz.inf.ontop.iq.node.impl.JoinOrFilterNodeImpl

checkExpression, getLocallyDefinedVariables, getLocallyRequiredVariables, getLocalVariables, getNullabilityEvaluator, getOptionalFilterCondition, getOptionalFilterString, isFilteringNullValue

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface it.unibz.inf.ontop.iq.node.JoinOrFilterNode

getOptionalFilterCondition

Methods inherited from interface it.unibz.inf.ontop.iq.node.QueryNode

getLocallyDefinedVariables, getLocallyRequiredVariables, getLocalVariables, getRequiredVariables

Method Detail

acceptVisitor

public void acceptVisitor(QueryNodeVisitor visitor)

Description copied from interface: QueryNode

"Accept" method for the "Visitor" pattern. To be implemented by leaf classes.

Specified by:

acceptVisitor in interface QueryNode

clone

public LeftJoinNode clone()

Description copied from class: QueryNodeImpl

See https://stackoverflow.com/questions/6837362/

Specified by:

clone in interface LeftJoinNode

Specified by:

clone in interface QueryNode

Overrides:

clone in class QueryNodeImpl

acceptNodeTransformer

public LeftJoinNode acceptNodeTransformer(HomogeneousQueryNodeTransformer transformer)
                                   throws QueryNodeTransformationException

Description copied from interface: QueryNode

"Accept" method for the "Visitor" pattern. To be implemented by leaf classes. If the transformation cannot be done, throw a QueryNodeTransformationException

Specified by:

acceptNodeTransformer in interface BinaryNonCommutativeOperatorNode

Specified by:

acceptNodeTransformer in interface LeftJoinNode

Specified by:

acceptNodeTransformer in interface QueryNode

Throws:

QueryNodeTransformationException

changeOptionalFilterCondition

public LeftJoinNode changeOptionalFilterCondition(Optional<ImmutableExpression> newOptionalFilterCondition)

Description copied from interface: JoinLikeNode

Constructs a new JoinLikeNode with the following optional filter condition (recall that a QueryNode is immutable).

Specified by:

changeOptionalFilterCondition in interface JoinLikeNode

Specified by:

changeOptionalFilterCondition in interface LeftJoinNode

isVariableNullable

public boolean isVariableNullable(IntermediateQuery query,
                                  Variable variable)

Description copied from interface: QueryNode

Returns true if it cannot guarantee the projected variable to be non-null Throws an IllegalArgumentException if the variable is not projected by the node

Specified by:

isVariableNullable in interface QueryNode

isSyntacticallyEquivalentTo

public boolean isSyntacticallyEquivalentTo(QueryNode node)

Description copied from interface: QueryNode

TODO: explain

Specified by:

isSyntacticallyEquivalentTo in interface QueryNode

isEquivalentTo

public boolean isEquivalentTo(QueryNode queryNode)

Description copied from interface: QueryNode

Is syntactically equivalent

Specified by:

isEquivalentTo in interface QueryNode

toString

public String toString()

Overrides:

toString in class Object

getVariableNullability

public VariableNullability getVariableNullability(IQTree leftChild,
                                                  IQTree rightChild)

Variable nullability for the full LJ tree

Specified by:

getVariableNullability in interface BinaryOrderedOperatorNode

getPossibleVariableDefinitions

public com.google.common.collect.ImmutableSet<ImmutableSubstitution<NonVariableTerm>> getPossibleVariableDefinitions(IQTree leftChild,
                                                                                                                     IQTree rightChild)

Returns possible definitions for left and right-specific variables.

Specified by:

getPossibleVariableDefinitions in interface BinaryOrderedOperatorNode

acceptTransformer

public IQTree acceptTransformer(IQTree tree,
                                IQTreeVisitingTransformer transformer,
                                IQTree leftChild,
                                IQTree rightChild)

Specified by:

acceptTransformer in interface BinaryOrderedOperatorNode

acceptVisitor

public <T> T acceptVisitor(IQVisitor<T> visitor,
                           IQTree leftChild,
                           IQTree rightChild)

Specified by:

acceptVisitor in interface BinaryOrderedOperatorNode

normalizeForOptimization

public IQTree normalizeForOptimization(IQTree initialLeftChild,
                                       IQTree initialRightChild,
                                       VariableGenerator variableGenerator,
                                       IQProperties currentIQProperties)

Specified by:

normalizeForOptimization in interface BinaryOrderedOperatorNode

liftIncompatibleDefinitions

public IQTree liftIncompatibleDefinitions(Variable variable,
                                          IQTree leftChild,
                                          IQTree rightChild,
                                          VariableGenerator variableGenerator)

Specified by:

liftIncompatibleDefinitions in interface BinaryOrderedOperatorNode

applyDescendingSubstitution

public IQTree applyDescendingSubstitution(ImmutableSubstitution<? extends VariableOrGroundTerm> descendingSubstitution,
                                          Optional<ImmutableExpression> constraint,
                                          IQTree leftChild,
                                          IQTree rightChild)

NB: the constraint is only propagate to the left child

Specified by:

applyDescendingSubstitution in interface BinaryOrderedOperatorNode

applyDescendingSubstitutionWithoutOptimizing

public IQTree applyDescendingSubstitutionWithoutOptimizing(ImmutableSubstitution<? extends VariableOrGroundTerm> descendingSubstitution,
                                                           IQTree leftChild,
                                                           IQTree rightChild)

Specified by:

applyDescendingSubstitutionWithoutOptimizing in interface BinaryOrderedOperatorNode

applyFreshRenaming

public IQTree applyFreshRenaming(InjectiveVar2VarSubstitution renamingSubstitution,
                                 IQTree leftChild,
                                 IQTree rightChild,
                                 IQTreeCache treeCache)

Specified by:

applyFreshRenaming in interface BinaryOrderedOperatorNode

isConstructed

public boolean isConstructed(Variable variable,
                             IQTree leftChild,
                             IQTree rightChild)

Specified by:

isConstructed in interface BinaryOrderedOperatorNode

isDistinct

public boolean isDistinct(IQTree leftChild,
                          IQTree rightChild)

Specified by:

isDistinct in interface BinaryOrderedOperatorNode

propagateDownConstraint

public IQTree propagateDownConstraint(ImmutableExpression constraint,
                                      IQTree leftChild,
                                      IQTree rightChild)

Specified by:

propagateDownConstraint in interface BinaryOrderedOperatorNode

validateNode

public void validateNode(IQTree leftChild,
                         IQTree rightChild)
                  throws InvalidIntermediateQueryException

Description copied from interface: BinaryOrderedOperatorNode

Only validates the node, not its children

Specified by:

validateNode in interface BinaryOrderedOperatorNode

Throws:

InvalidIntermediateQueryException

removeDistincts

public IQTree removeDistincts(IQTree leftChild,
                              IQTree rightChild,
                              IQProperties properties)

Specified by:

removeDistincts in interface BinaryOrderedOperatorNode

inferUniqueConstraints

public com.google.common.collect.ImmutableSet<com.google.common.collect.ImmutableSet<Variable>> inferUniqueConstraints(IQTree leftChild,
                                                                                                                       IQTree rightChild)

TODO: implement it seriously

Specified by:

inferUniqueConstraints in interface BinaryOrderedOperatorNode