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

Class DescribeIteration

java.lang.Object

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

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

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

All Implemented Interfaces:

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

public class DescribeIteration
extends LookAheadIteration<BindingSet,QueryEvaluationException>

Iteration that implements a simplified version of Symmetric Concise Bounded Description (omitting reified statements).

Author:

Jeen Broekstra

See Also:

Concise Bounded Description - alternatives

Constructor Summary

Constructors

Constructor and Description
DescribeIteration(Iteration<BindingSet,QueryEvaluationException> sourceIter, EvaluationStrategy strategy, Set<String> describeExprNames, BindingSet parentBindings)

Method Summary

Modifier and Type	Method and Description
protected BindingSet	getNextElement() Gets the next element.

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

handleClose, 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.Iteration

stream

Constructor Detail

DescribeIteration

public DescribeIteration(Iteration<BindingSet,QueryEvaluationException> sourceIter,
                         EvaluationStrategy strategy,
                         Set<String> describeExprNames,
                         BindingSet parentBindings)

Method Detail

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,QueryEvaluationException>

Returns:

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

Throws:

QueryEvaluationException