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

Class GroupIterator

java.lang.Object

org.eclipse.rdf4j.common.iteration.AbstractCloseableIteration<E,X>

org.eclipse.rdf4j.common.iteration.CloseableIteratorIteration<BindingSet,QueryEvaluationException>

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

All Implemented Interfaces:

AutoCloseable, CloseableIteration<BindingSet,QueryEvaluationException>, Iteration<BindingSet,QueryEvaluationException>

public class GroupIterator
extends CloseableIteratorIteration<BindingSet,QueryEvaluationException>

Author:

David Huynh, Arjohn Kampman, Jeen Broekstra, James Leigh, Jerven Bolleman

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	GroupIterator.Key	A unique key for a set of existing bindings.

Constructor Summary

Constructors

Constructor	Description
GroupIterator(EvaluationStrategy strategy, Group group, BindingSet parentBindings, long iterationCacheSyncThreshold, QueryEvaluationContext context)
GroupIterator(EvaluationStrategy strategy, Group group, BindingSet parentBindings, QueryEvaluationContext context)

Method Summary

Modifier and Type	Method	Description
protected void	handleClose()	Called by AbstractCloseableIteration.close() when it is called for the first time.
boolean	hasNext()	Returns true if the iteration has more elements.
BindingSet	next()	Returns the next element in the iteration.

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

hasIterator, remove, setIterator

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.Iteration

stream

Constructor Details

GroupIterator

public GroupIterator(EvaluationStrategy strategy,
 Group group,
 BindingSet parentBindings,
 QueryEvaluationContext context)
              throws QueryEvaluationException

Throws:

QueryEvaluationException

GroupIterator

public GroupIterator(EvaluationStrategy strategy,
 Group group,
 BindingSet parentBindings,
 long iterationCacheSyncThreshold,
 QueryEvaluationContext context)
              throws QueryEvaluationException

Throws:

QueryEvaluationException

Method Details

hasNext

public boolean hasNext()
                throws QueryEvaluationException

Description copied from interface: Iteration

Returns true if the iteration has more elements. (In other words, returns true if Iteration.next() would return an element rather than throwing a NoSuchElementException.)

Specified by:

hasNext in interface Iteration<BindingSet,QueryEvaluationException>

Overrides:

hasNext in class CloseableIteratorIteration<BindingSet,QueryEvaluationException>

Returns:

true if the iteration has more elements.

Throws:

QueryEvaluationException

next

public BindingSet next()
                throws QueryEvaluationException

Description copied from interface: Iteration

Returns the next element in the iteration.

Specified by:

next in interface Iteration<BindingSet,QueryEvaluationException>

Overrides:

next in class CloseableIteratorIteration<BindingSet,QueryEvaluationException>

Returns:

the next element in the iteration.

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.

Overrides:

handleClose in class AbstractCloseableIteration<BindingSet,QueryEvaluationException>

Throws:

QueryEvaluationException