org.apache.commons.collections4.iterators

Class SkippingIterator<E>

java.lang.Object

org.apache.commons.collections4.iterators.AbstractUntypedIteratorDecorator<E,E>

org.apache.commons.collections4.iterators.AbstractIteratorDecorator<E>

org.apache.commons.collections4.iterators.SkippingIterator<E>

All Implemented Interfaces:

java.util.Iterator<E>

public class SkippingIterator<E>
extends AbstractIteratorDecorator<E>

Decorates another iterator to skip the first N elements.

In case an offset parameter other than 0 is provided, the decorated iterator is immediately advanced to this position, skipping all elements before that position.

Since:

4.1

Field Summary

Fields

Modifier and Type	Field and Description
private long	offset The offset to bound the first element return
private long	pos The position of the current element

Constructor Summary

Constructors

Constructor and Description
SkippingIterator(java.util.Iterator<E> iterator, long offset) Decorates the specified iterator to skip all elements until the iterator reaches the position at offset.

Method Summary

Modifier and Type	Method and Description
private void	init() Skips the given number of elements.
E	next()
void	remove()

Methods inherited from class org.apache.commons.collections4.iterators.AbstractUntypedIteratorDecorator

getIterator, hasNext

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining

Field Detail

offset

private final long offset

The offset to bound the first element return

pos

private long pos

The position of the current element

Constructor Detail

SkippingIterator

public SkippingIterator(java.util.Iterator<E> iterator,
                        long offset)

Decorates the specified iterator to skip all elements until the iterator reaches the position at offset.

The iterator is immediately advanced until it reaches the position at offset, incurring O(n) time.

Parameters:

iterator - the iterator to be decorated

offset - the index of the first element of the decorated iterator to return

Throws:

java.lang.NullPointerException - if iterator is null

java.lang.IllegalArgumentException - if offset is negative

Method Detail

init

private void init()

Skips the given number of elements.

next

public E next()

Description copied from class: AbstractIteratorDecorator

Specified by:

next in interface java.util.Iterator<E>

Overrides:

next in class AbstractIteratorDecorator<E>

remove

public void remove()

In case an offset other than 0 was specified, the underlying iterator will be advanced to this position upon creation. A call to remove() will still result in an IllegalStateException if no explicit call to next() has been made prior to calling remove().

Specified by:

remove in interface java.util.Iterator<E>

Overrides:

remove in class AbstractUntypedIteratorDecorator<E,E>