Package org.eclipse.rdf4j.common.iteration

Class ConvertingIteration<S,T>

java.lang.Object

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

org.eclipse.rdf4j.common.iteration.ConvertingIteration<S,T>

All Implemented Interfaces:

AutoCloseable, Iterator<T>, CloseableIteration<T>

Direct Known Subclasses:

BoundJoinConversionIteration, BoundJoinVALUESConversionIteration, ExtensionIterator, GroupedCheckConversionIteration, InsertBindingsIteration, ProjectionIterator, ServiceJoinConversionIteration

public abstract class ConvertingIteration<S,T>
extends AbstractCloseableIteration<T>

A CloseableIteration that converts an iteration over objects of type S (the source type) to an iteration over objects of type T (the target type).

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ConvertingIteration(CloseableIteration<? extends S> iter)	Creates a new ConvertingIteration that operates on the supplied source type iteration.

Method Summary

Modifier and Type	Method	Description
protected abstract T	convert(S sourceObject)	Converts a source type object to a target type object.
protected void	handleClose()	Closes this iteration as well as the wrapped iteration if it is a CloseableIteration.
final boolean	hasNext()	Checks whether the source type iteration contains more elements.
final T	next()	Returns the next element from the source type iteration.
final void	remove()	Calls remove() on the underlying Iteration.

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

ConvertingIteration

protected ConvertingIteration(CloseableIteration<? extends S> iter)

Creates a new ConvertingIteration that operates on the supplied source type iteration.

Parameters:

iter - The source type iteration for this ConvertingIteration, must not be null.

Method Details

convert

protected abstract T convert(S sourceObject)

Converts a source type object to a target type object.

hasNext

public final boolean hasNext()

Checks whether the source type iteration contains more elements.

Returns:

true if the source type iteration contains more elements, false otherwise.

next

public final T next()

Returns the next element from the source type iteration.

Throws:

NoSuchElementException - If all elements have been returned.

IllegalStateException - If the iteration has been closed.

remove

public final void remove()

Calls remove() on the underlying Iteration.

Throws:

UnsupportedOperationException - If the wrapped Iteration does not support the remove operation.

IllegalStateException - If the Iteration has been closed, or if next() has not yet been called, or remove() has already been called after the last call to next().

handleClose

protected void handleClose()

Closes this iteration as well as the wrapped iteration if it is a CloseableIteration.

Specified by:

handleClose in class AbstractCloseableIteration<T>