Package org.eclipse.rdf4j.query.algebra.evaluation.iterator

Class PathIteration

java.lang.Object

org.eclipse.rdf4j.common.iteration.AbstractCloseableIteration<BindingSet>

org.eclipse.rdf4j.common.iteration.LookAheadIteration<BindingSet>

org.eclipse.rdf4j.query.algebra.evaluation.iterator.PathIteration

All Implemented Interfaces:

AutoCloseable, Iterator<BindingSet>, CloseableIteration<BindingSet>

public class PathIteration
extends LookAheadIteration<BindingSet>

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	PathIteration.ValuePair	A specialized BingingSet that can only hold the start and end values of a Path.

Constructor Summary

Constructors

Constructor	Description
PathIteration(EvaluationStrategy strategy, StatementPattern.Scope scope, Var startVar, TupleExpr pathExpression, Var endVar, Var contextVar, long minLength, BindingSet bindings)

Method Summary

Modifier and Type	Method	Description
protected boolean	add(Set<BindingSet> valueSet, PathIteration.ValuePair vp)
protected boolean	addToQueue(Queue<BindingSet> valueQueue2, PathIteration.ValuePair vp)
static final Function<BindingSet,Value>	getGet(String s)	Used to turn a method call into a direct field access
static final Predicate<BindingSet>	getHas(String s)	Used to turn a method call into a direct field access
protected BindingSet	getNextElement()	Gets the next element.
static final BiConsumer<Value,MutableBindingSet>	getSet(String s)	Used to turn a method call into a direct field access
protected void	handleClose()	Called by AbstractCloseableIteration.close() when it is called for the first time.
protected boolean	isUnbound(Var var, BindingSet bindings)

Methods inherited from class org.eclipse.rdf4j.common.iteration.LookAheadIteration

hasNext, next, remove

Methods inherited from class org.eclipse.rdf4j.common.iteration.AbstractCloseableIteration

close, isClosed

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.eclipse.rdf4j.common.iteration.CloseableIteration

stream

Methods inherited from interface java.util.Iterator

forEachRemaining

Constructor Details

PathIteration

public PathIteration(EvaluationStrategy strategy,
 StatementPattern.Scope scope,
 Var startVar,
 TupleExpr pathExpression,
 Var endVar,
 Var contextVar,
 long minLength,
 BindingSet bindings)
              throws QueryEvaluationException

Throws:

QueryEvaluationException

Method Details

getSet

@InternalUseOnly
public static final BiConsumer<Value,MutableBindingSet> getSet(String s)

Used to turn a method call into a direct field access

Parameters:

s - the name of the variable to see if it is in the bindingset

Returns:

the value of the start or end or if asked for a different field a null.

getGet

public static final Function<BindingSet,Value> getGet(String s)

Used to turn a method call into a direct field access

Parameters:

s - the name of the variable to see if it is in the bindingset

Returns:

the value of the start or end, if asked for a different field throw an illegalstate exception

getHas

public static final Predicate<BindingSet> getHas(String s)

Used to turn a method call into a direct field access

Parameters:

s - the name of the variable to see if it is in the bindingset

Returns:

true if start or end is not null, if asked for a different field throw an illegalstate exception

getNextElement

protected BindingSet getNextElement()
                             throws QueryEvaluationException

Description copied from class: LookAheadIteration

Gets the next element. Subclasses should implement this method so that it returns the next element.

Specified by:

getNextElement in class LookAheadIteration<BindingSet>

Returns:

The next element, or null if no more elements are available.

Throws:

QueryEvaluationException

handleClose

protected void handleClose()
                    throws QueryEvaluationException

Description copied from class: AbstractCloseableIteration

Called by AbstractCloseableIteration.close() when it is called for the first time. This method is only called once on each iteration. By default, this method does nothing.

Specified by:

handleClose in class AbstractCloseableIteration<BindingSet>

Throws:

QueryEvaluationException

addToQueue

protected boolean addToQueue(Queue<BindingSet> valueQueue2,
 PathIteration.ValuePair vp)
                      throws QueryEvaluationException

Parameters:

valueQueue2 -

vp -

Throws:

QueryEvaluationException

add

protected boolean add(Set<BindingSet> valueSet,
 PathIteration.ValuePair vp)
               throws QueryEvaluationException

Parameters:

valueSet -

vp -

Throws:

QueryEvaluationException

isUnbound

protected boolean isUnbound(Var var,
 BindingSet bindings)