Class LookAheadIterator<E>

java.lang.Object

org.eclipse.rdf4j.common.iterator.AbstractCloseableIterator<E>

org.eclipse.rdf4j.common.iterator.LookAheadIterator<E>

All Implemented Interfaces:

Closeable, AutoCloseable, Iterator<E>

Direct Known Subclasses:

UnionIterator

public abstract class LookAheadIterator<E>
extends AbstractCloseableIterator<E>

Field Summary

Fields

Modifier and Type	Field	Description
private IOException	closeException
private E	nextElement

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	LookAheadIterator()

Method Summary

Modifier and Type	Method	Description
protected abstract E	getNextElement()	Gets the next element.
protected void	handleAlreadyClosed()
protected void	handleClose()	Called by AbstractCloseableIterator.close() when it is called for the first time.
final boolean	hasNext()
private void	lookAhead()	Fetches the next element if it hasn't been fetched yet and stores it in nextElement.
final E	next()
void	remove()	Throws an UnsupportedOperationException.

Methods inherited from class AbstractCloseableIterator

close, isClosed

Methods inherited from class Object

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

Methods inherited from interface Iterator

forEachRemaining

Field Details

nextElement

private E nextElement

closeException

private IOException closeException

Constructor Details

LookAheadIterator

protected LookAheadIterator()

Method Details

getNextElement

protected abstract E getNextElement()

Gets the next element. Subclasses should implement this method so that it returns the next element.

Returns:

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

hasNext

public final boolean hasNext()

next

public final E next()

lookAhead

private void lookAhead()

Fetches the next element if it hasn't been fetched yet and stores it in nextElement.

remove

public void remove()

Throws an UnsupportedOperationException.

handleClose

protected void handleClose()
                    throws IOException

Description copied from class: AbstractCloseableIterator

Called by AbstractCloseableIterator.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 AbstractCloseableIterator<E>

Throws:

IOException

handleAlreadyClosed

protected void handleAlreadyClosed()
                            throws IOException

Overrides:

handleAlreadyClosed in class AbstractCloseableIterator<E>

Throws:

IOException