Package org.eclipse.rdf4j.federated.algebra

Class CheckStatementPattern

java.lang.Object

org.eclipse.rdf4j.federated.algebra.CheckStatementPattern

All Implemented Interfaces:

Serializable, Cloneable, BoundJoinTupleExpr, FedXTupleExpr, QueryRef, StatementTupleExpr, VariableExpr, QueryModelNode, TupleExpr

public class CheckStatementPattern
extends Object
implements StatementTupleExpr, BoundJoinTupleExpr

A statement pattern with no free variables when provided with some particular BindingSet in evaluate. For evaluation a boolean ASK query is performed. Wraps a StatementTupleExpr

Author:

Andreas Schwarte

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected final String	id
protected final QueryInfo	queryInfo
protected final StatementTupleExpr	stmt

Constructor Summary

Constructors

Constructor	Description
CheckStatementPattern(StatementTupleExpr stmt, QueryInfo queryInfo)

Method Summary

Modifier and Type	Method	Description
CheckStatementPattern	clone()	Returns a (deep) clone of this query model node.
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(BindingSet bindings)	Evaluate this expression using the provided bindings
Set<String>	getAssuredBindingNames()	Gets the names of the bindings that are guaranteed to be present in the results produced by this tuple expression.
Set<String>	getBindingNames()	Gets the names of the bindings that are, or can be, returned by this tuple expression when it is evaluated.
double	getCostEstimate()
int	getFreeVarCount()
List<String>	getFreeVars()
String	getId()
QueryModelNode	getParentNode()	Gets the node's parent.
QueryInfo	getQueryInfo()	Retrieve the attached query information of the tuple expression
long	getResultSizeActual()
double	getResultSizeEstimate()	Returns the number of tuples that this QueryNode predicts will be outputted.
String	getSignature()	Returns the signature of this query model node.
StatementPattern	getStatementPattern()
List<StatementSource>	getStatementSources()
long	getTotalTimeNanosActual()
boolean	hasFreeVarsFor(BindingSet binding)	returns true iff this statement has free variables in the presence of the specified binding set
void	replaceChildNode(QueryModelNode current, QueryModelNode replacement)	Replaces one of the child nodes with a new node.
void	replaceWith(QueryModelNode replacement)	Substitutes this node with a new node in the query model tree.
void	setCostEstimate(double costEstimate)
void	setParentNode(QueryModelNode parent)	Sets the node's parent.
void	setResultSizeActual(long resultSizeActual)
void	setResultSizeEstimate(double resultSizeEstimate)
void	setTotalTimeNanosActual(long totalTimeNanosActual)
<X extends Exception> void	visit(QueryModelVisitor<X> visitor)	Visits this node.
<X extends Exception> void	visitChildren(QueryModelVisitor<X> visitor)	Visits the children of this node.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.eclipse.rdf4j.query.algebra.QueryModelNode

equals, toString

Field Details

stmt

protected final StatementTupleExpr stmt

id

protected final String id

queryInfo

protected final QueryInfo queryInfo

Constructor Details

CheckStatementPattern

public CheckStatementPattern(StatementTupleExpr stmt,
 QueryInfo queryInfo)

Method Details

getStatementPattern

public StatementPattern getStatementPattern()

getFreeVarCount

public int getFreeVarCount()

Specified by:

getFreeVarCount in interface FedXTupleExpr

Returns:

the number of free (i.e. unbound) variables in this expression

getFreeVars

public List<String> getFreeVars()

Specified by:

getFreeVars in interface VariableExpr

Returns:

a list of free (i.e. unbound) variables in this expression

getId

public String getId()

Specified by:

getId in interface StatementTupleExpr

Returns:

the id of this expr

getStatementSources

public List<StatementSource> getStatementSources()

Specified by:

getStatementSources in interface StatementTupleExpr

Returns:

a list of sources that are relevant for evaluation of this expression

hasFreeVarsFor

public boolean hasFreeVarsFor(BindingSet binding)

Description copied from interface: StatementTupleExpr

returns true iff this statement has free variables in the presence of the specified binding set

Specified by:

hasFreeVarsFor in interface StatementTupleExpr

Returns:

whether the statement has free vars

getAssuredBindingNames

public Set<String> getAssuredBindingNames()

Description copied from interface: TupleExpr

Gets the names of the bindings that are guaranteed to be present in the results produced by this tuple expression.

Specified by:

getAssuredBindingNames in interface TupleExpr

Returns:

A set of binding names.

getBindingNames

public Set<String> getBindingNames()

Description copied from interface: TupleExpr

Gets the names of the bindings that are, or can be, returned by this tuple expression when it is evaluated.

Specified by:

getBindingNames in interface TupleExpr

Returns:

A set of binding names.

getParentNode

public QueryModelNode getParentNode()

Description copied from interface: QueryModelNode

Gets the node's parent.

Specified by:

getParentNode in interface QueryModelNode

Returns:

The parent node, if any.

getSignature

public String getSignature()

Description copied from interface: QueryModelNode

Returns the signature of this query model node. Signatures normally include the node's name and any parameters, but not parent or child nodes. This method is used by QueryModelNode.toString().

Specified by:

getSignature in interface QueryModelNode

Returns:

The node's signature, e.g. SLICE (offset=10, limit=10).

replaceChildNode

public void replaceChildNode(QueryModelNode current,
 QueryModelNode replacement)

Description copied from interface: QueryModelNode

Replaces one of the child nodes with a new node.

Specified by:

replaceChildNode in interface QueryModelNode

Parameters:

current - The current child node.

replacement - The new child node.

replaceWith

public void replaceWith(QueryModelNode replacement)

Description copied from interface: QueryModelNode

Substitutes this node with a new node in the query model tree.

Specified by:

replaceWith in interface QueryModelNode

Parameters:

replacement - The new node.

setParentNode

public void setParentNode(QueryModelNode parent)

Description copied from interface: QueryModelNode

Sets the node's parent.

Specified by:

setParentNode in interface QueryModelNode

Parameters:

parent - The parent node for this node.

visit

public <X extends Exception> void visit(QueryModelVisitor<X> visitor)
                                 throws X

Description copied from interface: QueryModelNode

Visits this node. The node reports itself to the visitor with the proper runtime type.

Specified by:

visit in interface QueryModelNode

Throws:

X extends Exception

visitChildren

public <X extends Exception> void visitChildren(QueryModelVisitor<X> visitor)
                                         throws X

Description copied from interface: QueryModelNode

Visits the children of this node. The node calls QueryModelNode.visit(QueryModelVisitor) on all of its child nodes.

Specified by:

visitChildren in interface QueryModelNode

Throws:

X extends Exception

clone

public CheckStatementPattern clone()

Description copied from interface: QueryModelNode

Returns a (deep) clone of this query model node. This method recursively clones the entire node tree, starting from this nodes.

Specified by:

clone in interface QueryModelNode

Specified by:

clone in interface TupleExpr

Overrides:

clone in class Object

Returns:

A deep clone of this query model node.

getResultSizeEstimate

public double getResultSizeEstimate()

Description copied from interface: QueryModelNode

Returns the number of tuples that this QueryNode predicts will be outputted. For a StatementPattern this would be the estimated cardinality provided by the EvaluationStatistics. For a Join the would be the resulting number of joined tuples.

Specified by:

getResultSizeEstimate in interface QueryModelNode

Returns:

rows

setResultSizeEstimate

public void setResultSizeEstimate(double resultSizeEstimate)

Specified by:

setResultSizeEstimate in interface QueryModelNode

getResultSizeActual

public long getResultSizeActual()

Specified by:

getResultSizeActual in interface QueryModelNode

setResultSizeActual

public void setResultSizeActual(long resultSizeActual)

Specified by:

setResultSizeActual in interface QueryModelNode

getCostEstimate

public double getCostEstimate()

Specified by:

getCostEstimate in interface QueryModelNode

setCostEstimate

public void setCostEstimate(double costEstimate)

Specified by:

setCostEstimate in interface QueryModelNode

getTotalTimeNanosActual

public long getTotalTimeNanosActual()

Specified by:

getTotalTimeNanosActual in interface QueryModelNode

setTotalTimeNanosActual

public void setTotalTimeNanosActual(long totalTimeNanosActual)

Specified by:

setTotalTimeNanosActual in interface QueryModelNode

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(BindingSet bindings)
                                                                 throws QueryEvaluationException

Description copied from interface: StatementTupleExpr

Evaluate this expression using the provided bindings

Specified by:

evaluate in interface StatementTupleExpr

Returns:

the result iteration

Throws:

QueryEvaluationException

getQueryInfo

public QueryInfo getQueryInfo()

Description copied from interface: QueryRef

Retrieve the attached query information of the tuple expression

Specified by:

getQueryInfo in interface QueryRef

Returns:

the QueryInfo