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

Class LeftJoinIterator

java.lang.Object

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

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

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

All Implemented Interfaces:

AutoCloseable, Iterator<BindingSet>, CloseableIteration<BindingSet>

Direct Known Subclasses:

BadlyDesignedLeftJoinIterator

public class LeftJoinIterator
extends LookAheadIteration<BindingSet>

Constructor Summary

Constructors

Constructor	Description
LeftJoinIterator(CloseableIteration<BindingSet> leftIter, QueryEvaluationStep prepareRightArg, QueryValueEvaluationStep joinCondition, Set<String> scopeBindingNamse)
LeftJoinIterator(EvaluationStrategy strategy, LeftJoin join, BindingSet bindings, QueryEvaluationContext context)
LeftJoinIterator(QueryEvaluationStep left, QueryEvaluationStep right, QueryValueEvaluationStep joinCondition, BindingSet bindings, Set<String> scopeBindingNamse)

Method Summary

Modifier and Type	Method	Description
static CloseableIteration<BindingSet>	getInstance(QueryEvaluationStep left, QueryEvaluationStep prepareRightArg, QueryValueEvaluationStep joinCondition, BindingSet bindings, Set<String> scopeBindingNamse)
protected BindingSet	getNextElement()	Gets the next element.
protected void	handleClose()	Called by AbstractCloseableIteration.close() when it is called for the first time.

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

LeftJoinIterator

public LeftJoinIterator(EvaluationStrategy strategy,
 LeftJoin join,
 BindingSet bindings,
 QueryEvaluationContext context)
                 throws QueryEvaluationException

Throws:

QueryEvaluationException

LeftJoinIterator

public LeftJoinIterator(QueryEvaluationStep left,
 QueryEvaluationStep right,
 QueryValueEvaluationStep joinCondition,
 BindingSet bindings,
 Set<String> scopeBindingNamse)
                 throws QueryEvaluationException

Throws:

QueryEvaluationException

LeftJoinIterator

public LeftJoinIterator(CloseableIteration<BindingSet> leftIter,
 QueryEvaluationStep prepareRightArg,
 QueryValueEvaluationStep joinCondition,
 Set<String> scopeBindingNamse)

Method Details

getInstance

public static CloseableIteration<BindingSet> getInstance(QueryEvaluationStep left,
 QueryEvaluationStep prepareRightArg,
 QueryValueEvaluationStep joinCondition,
 BindingSet bindings,
 Set<String> scopeBindingNamse)

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