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

Class ConstructionNodeImpl

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.ExtendedProjectionNodeImpl

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

All Implemented Interfaces:

ConstructionNode, ExplicitVariableProjectionNode, ExtendedProjectionNode, QueryNode, UnaryOperatorNode, Cloneable

public class ConstructionNodeImpl
extends ExtendedProjectionNodeImpl
implements ConstructionNode

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ConstructionNodeImpl.PropagationResults<T extends VariableOrGroundTerm>

Nested classes/interfaces inherited from class it.unibz.inf.ontop.iq.node.impl.ExtendedProjectionNodeImpl

ExtendedProjectionNodeImpl.DescendingSubstitutionChildUpdateFunction, ExtendedProjectionNodeImpl.EmptyTreeException

Method Summary

Modifier and Type	Method and Description
ConstructionNode	acceptNodeTransformer(HomogeneousQueryNodeTransformer transformer) "Accept" method for the "Visitor" pattern.
IQTree	acceptTransformer(IQTree tree, IQTreeVisitingTransformer transformer, IQTree child)
<T> T	acceptVisitor(IQVisitor<T> visitor, IQTree child)
void	acceptVisitor(QueryNodeVisitor visitor) "Accept" method for the "Visitor" pattern.
IQTree	applyFreshRenaming(InjectiveVar2VarSubstitution renamingSubstitution, IQTree child, IQTreeCache treeCache)
ConstructionNode	clone() Immutable fields, can be shared.
protected Optional<ExtendedProjectionNode>	computeNewProjectionNode(com.google.common.collect.ImmutableSet<Variable> newProjectedVariables, ImmutableSubstitution<ImmutableTerm> theta, IQTree newChild)
com.google.common.collect.ImmutableSet<Variable>	getChildVariables() Variables that have to be provided by the child
com.google.common.collect.ImmutableSet<Variable>	getLocallyDefinedVariables() Locally defined variables must not appear in the sub-tree
com.google.common.collect.ImmutableSet<Variable>	getLocallyRequiredVariables() Set of variables that this node, INDEPENDENTLY OF THE REQUIREMENTS OF ITS ANCESTORS, requires to be defined in the sub-tree.
com.google.common.collect.ImmutableSet<Variable>	getLocalVariables() Set of variables MENTIONED in the node, INDEPENDENTLY of its sub-tree.
com.google.common.collect.ImmutableSet<ImmutableSubstitution<NonVariableTerm>>	getPossibleVariableDefinitions(IQTree child)
com.google.common.collect.ImmutableSet<Variable>	getRequiredVariables(IntermediateQuery query) Set of variables which, individually, must be provided by at least one child, INDEPENDENTLY OF THE REQUIREMENTS OF THIS NODE'S ANCESTORS.
ImmutableSubstitution<ImmutableTerm>	getSubstitution() (Some) projected variable --> transformed variable
com.google.common.collect.ImmutableSet<Variable>	getVariables() Set of variables returned by any sub-tree where this node is the root.
com.google.common.collect.ImmutableSet<com.google.common.collect.ImmutableSet<Variable>>	inferUniqueConstraints(IQTree child)
boolean	isDistinct(IQTree child)
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 child, VariableGenerator variableGenerator)
IQTree	normalizeForOptimization(IQTree child, VariableGenerator variableGenerator, IQProperties currentIQProperties) - Merges with a child construction - Removes itself if useless
IQTree	removeDistincts(IQTree child, IQProperties iqProperties)
String	toString()
void	validateNode(IQTree child) Only validates the node, not its child

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

applyDescendingSubstitution, applyDescendingSubstitutionWithoutOptimizing, getVariableNullability, isConstructed, propagateDownConstraint

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.UnaryOperatorNode

applyDescendingSubstitution, applyDescendingSubstitutionWithoutOptimizing, getVariableNullability, isConstructed, propagateDownConstraint

Method Detail

getVariables

public com.google.common.collect.ImmutableSet<Variable> getVariables()

Description copied from interface: ExplicitVariableProjectionNode

Set of variables returned by any sub-tree where this node is the root.

Specified by:

getVariables in interface ExplicitVariableProjectionNode

getSubstitution

public ImmutableSubstitution<ImmutableTerm> getSubstitution()

Description copied from interface: ExtendedProjectionNode

(Some) projected variable --> transformed variable

Specified by:

getSubstitution in interface ConstructionNode

Specified by:

getSubstitution in interface ExtendedProjectionNode

clone

public ConstructionNode clone()

Immutable fields, can be shared.

Specified by:

clone in interface ConstructionNode

Specified by:

clone in interface QueryNode

Overrides:

clone in class QueryNodeImpl

acceptNodeTransformer

public ConstructionNode 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 ConstructionNode

Specified by:

acceptNodeTransformer in interface QueryNode

Specified by:

acceptNodeTransformer in interface UnaryOperatorNode

Throws:

QueryNodeTransformationException

getChildVariables

public com.google.common.collect.ImmutableSet<Variable> getChildVariables()

Description copied from interface: ExtendedProjectionNode

Variables that have to be provided by the child

Specified by:

getChildVariables in interface ExtendedProjectionNode

getLocalVariables

public com.google.common.collect.ImmutableSet<Variable> getLocalVariables()

Description copied from interface: QueryNode

Set of variables MENTIONED in the node, INDEPENDENTLY of its sub-tree. See ImmutableQuery.getVariables(QueryNode node) for getting all the variables returned by the QueryNode.

Specified by:

getLocalVariables in interface QueryNode

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

isDistinct

public boolean isDistinct(IQTree child)

Specified by:

isDistinct in interface UnaryOperatorNode

liftIncompatibleDefinitions

public IQTree liftIncompatibleDefinitions(Variable variable,
                                          IQTree child,
                                          VariableGenerator variableGenerator)

Specified by:

liftIncompatibleDefinitions in interface UnaryOperatorNode

acceptTransformer

public IQTree acceptTransformer(IQTree tree,
                                IQTreeVisitingTransformer transformer,
                                IQTree child)

Specified by:

acceptTransformer in interface UnaryOperatorNode

acceptVisitor

public <T> T acceptVisitor(IQVisitor<T> visitor,
                           IQTree child)

Specified by:

acceptVisitor in interface UnaryOperatorNode

validateNode

public void validateNode(IQTree child)
                  throws InvalidQueryNodeException,
                         InvalidIntermediateQueryException

Description copied from interface: UnaryOperatorNode

Only validates the node, not its child

Specified by:

validateNode in interface UnaryOperatorNode

Throws:

InvalidQueryNodeException

InvalidIntermediateQueryException

getPossibleVariableDefinitions

public com.google.common.collect.ImmutableSet<ImmutableSubstitution<NonVariableTerm>> getPossibleVariableDefinitions(IQTree child)

Specified by:

getPossibleVariableDefinitions in interface UnaryOperatorNode

removeDistincts

public IQTree removeDistincts(IQTree child,
                              IQProperties iqProperties)

Specified by:

removeDistincts in interface UnaryOperatorNode

inferUniqueConstraints

public com.google.common.collect.ImmutableSet<com.google.common.collect.ImmutableSet<Variable>> inferUniqueConstraints(IQTree child)

Specified by:

inferUniqueConstraints in interface UnaryOperatorNode

isSyntacticallyEquivalentTo

public boolean isSyntacticallyEquivalentTo(QueryNode node)

Description copied from interface: QueryNode

TODO: explain

Specified by:

isSyntacticallyEquivalentTo in interface QueryNode

getLocallyRequiredVariables

public com.google.common.collect.ImmutableSet<Variable> getLocallyRequiredVariables()

Description copied from interface: QueryNode

Set of variables that this node, INDEPENDENTLY OF THE REQUIREMENTS OF ITS ANCESTORS, requires to be defined in the sub-tree. Said differently, additional variable requirements may come from its ancestors.

Specified by:

getLocallyRequiredVariables in interface QueryNode

getRequiredVariables

public com.google.common.collect.ImmutableSet<Variable> getRequiredVariables(IntermediateQuery query)

Description copied from interface: QueryNode

Set of variables which, individually, must be provided by at least one child, INDEPENDENTLY OF THE REQUIREMENTS OF THIS NODE'S ANCESTORS. This may extend locally required variables. For instance, for a join node, this includes variables used in implicit joining conditions

Specified by:

getRequiredVariables in interface QueryNode

getLocallyDefinedVariables

public com.google.common.collect.ImmutableSet<Variable> getLocallyDefinedVariables()

Description copied from interface: QueryNode

Locally defined variables must not appear in the sub-tree

Specified by:

getLocallyDefinedVariables in interface QueryNode

isEquivalentTo

public boolean isEquivalentTo(QueryNode queryNode)

Description copied from interface: QueryNode

Is syntactically equivalent

Specified by:

isEquivalentTo in interface QueryNode

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

toString

public String toString()

Overrides:

toString in class Object

normalizeForOptimization

public IQTree normalizeForOptimization(IQTree child,
                                       VariableGenerator variableGenerator,
                                       IQProperties currentIQProperties)

- Merges with a child construction - Removes itself if useless

Specified by:

normalizeForOptimization in interface UnaryOperatorNode

applyFreshRenaming

public IQTree applyFreshRenaming(InjectiveVar2VarSubstitution renamingSubstitution,
                                 IQTree child,
                                 IQTreeCache treeCache)

Specified by:

applyFreshRenaming in interface UnaryOperatorNode

computeNewProjectionNode

protected Optional<ExtendedProjectionNode> computeNewProjectionNode(com.google.common.collect.ImmutableSet<Variable> newProjectedVariables,
                                                                    ImmutableSubstitution<ImmutableTerm> theta,
                                                                    IQTree newChild)

Specified by:

computeNewProjectionNode in class ExtendedProjectionNodeImpl