Module org.apache.jena.base

Package org.apache.jena.atlas.iterator

Class PeekIterator<T>

java.lang.Object

org.apache.jena.atlas.iterator.PeekIterator<T>

All Implemented Interfaces:

Iterator<T>

public class PeekIterator<T>
extends Object
implements Iterator<T>

PeekIterator - it is one slot ahead reading from the wrapped iterator.

Constructor Summary

Constructors

Constructor	Description
PeekIterator(Iterator<T> iter)

Method Summary

Modifier and Type	Method	Description
static <T> PeekIterator<T>	create(Iterator<T> iter)
static <T> PeekIterator<T>	create(PeekIterator<T> iter)
T	element()	Peek the next element or throw NoSuchElementException
boolean	hasNext()
T	next()
T	peek()	Peek the next element or return null This code predates Optional.
boolean	slotIsValid()	Return whether the peek'ed element exists of not.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining, remove

Constructor Details

PeekIterator

public PeekIterator(Iterator<T> iter)

Method Details

create

public static <T> PeekIterator<T> create(PeekIterator<T> iter)

create

public static <T> PeekIterator<T> create(Iterator<T> iter)

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<T>

peek

public T peek()

Peek the next element or return null This code predates Optional. See "slotIsValid()" to check if a null is end-of-iterator or a valid return element.

slotIsValid

public boolean slotIsValid()

Return whether the peek'ed element exists of not. When the underlying iterator may yield null as a valid value of "next", use this to determine the status of the "peek()". This code predates Optional.

element

public T element()

Peek the next element or throw NoSuchElementException

next

public T next()

Specified by:

next in interface Iterator<T>