org.openrdf.query.algebra.evaluation.iterator

Class OrderIterator

java.lang.Object

info.aduna.iteration.AbstractCloseableIteration<E,X>

info.aduna.iteration.DelayedIteration<BindingSet,QueryEvaluationException>

org.openrdf.query.algebra.evaluation.iterator.OrderIterator

All Implemented Interfaces:

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

Direct Known Subclasses:

LimitedSizeOrderIteration

public class OrderIterator
extends DelayedIteration<BindingSet,QueryEvaluationException>

Sorts the input and optionally applies limit and distinct.

Author:

James Leigh, Arjohn Kampman

Constructor Summary

Constructors

Constructor and Description
OrderIterator(CloseableIteration<BindingSet,QueryEvaluationException> iter, Comparator<BindingSet> comparator)
OrderIterator(CloseableIteration<BindingSet,QueryEvaluationException> iter, Comparator<BindingSet> comparator, long limit, boolean distinct)
OrderIterator(CloseableIteration<BindingSet,QueryEvaluationException> iter, Comparator<BindingSet> comparator, long limit, boolean distinct, long iterationSyncThreshold)

Method Summary

Modifier and Type	Method and Description
protected boolean	add(BindingSet next, Collection<BindingSet> list)
protected Iteration<BindingSet,QueryEvaluationException>	createIteration() Creates the iteration that should be iterated over.
protected void	handleClose() Closes this iteration as well as the underlying iteration if it has already been created and happens to be a CloseableIteration.
protected NavigableMap<BindingSet,Integer>	makeOrderedMap()
protected Integer	put(NavigableMap<BindingSet,Integer> map, BindingSet set, int count)
void	remove() Calls the remove method of the underlying iteration.
protected void	removeLast(Collection<BindingSet> lastResults)

Methods inherited from class info.aduna.iteration.DelayedIteration

hasNext, next

Methods inherited from class info.aduna.iteration.AbstractCloseableIteration

close, isClosed

Methods inherited from class java.lang.Object

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

Constructor Detail

OrderIterator

public OrderIterator(CloseableIteration<BindingSet,QueryEvaluationException> iter,
                     Comparator<BindingSet> comparator)

OrderIterator

public OrderIterator(CloseableIteration<BindingSet,QueryEvaluationException> iter,
                     Comparator<BindingSet> comparator,
                     long limit,
                     boolean distinct)

OrderIterator

public OrderIterator(CloseableIteration<BindingSet,QueryEvaluationException> iter,
                     Comparator<BindingSet> comparator,
                     long limit,
                     boolean distinct,
                     long iterationSyncThreshold)

Method Detail

makeOrderedMap

protected NavigableMap<BindingSet,Integer> makeOrderedMap()

createIteration

protected Iteration<BindingSet,QueryEvaluationException> createIteration()
                                                                  throws QueryEvaluationException

Description copied from class: DelayedIteration

Creates the iteration that should be iterated over. This method is called only once, when the iteration is first needed.

Specified by:

createIteration in class DelayedIteration<BindingSet,QueryEvaluationException>

Throws:

QueryEvaluationException

removeLast

protected void removeLast(Collection<BindingSet> lastResults)

add

protected boolean add(BindingSet next,
                      Collection<BindingSet> list)
               throws QueryEvaluationException

Throws:

QueryEvaluationException

put

protected Integer put(NavigableMap<BindingSet,Integer> map,
                      BindingSet set,
                      int count)
               throws QueryEvaluationException

Throws:

QueryEvaluationException

remove

public void remove()
            throws QueryEvaluationException

Description copied from class: DelayedIteration

Calls the remove method of the underlying iteration.

Specified by:

remove in interface Iteration<BindingSet,QueryEvaluationException>

Overrides:

remove in class DelayedIteration<BindingSet,QueryEvaluationException>

Throws:

QueryEvaluationException

handleClose

protected void handleClose()
                    throws QueryEvaluationException

Description copied from class: DelayedIteration

Closes this iteration as well as the underlying iteration if it has already been created and happens to be a CloseableIteration.

Overrides:

handleClose in class DelayedIteration<BindingSet,QueryEvaluationException>

Throws:

QueryEvaluationException