org.apache.jackrabbit.oak.jcr.query
Class PrefetchIterator<K>

java.lang.Object
  org.apache.jackrabbit.oak.jcr.query.PrefetchIterator<K>

Type Parameters:

K - the iterator data type

All Implemented Interfaces:

Iterator<K>

public class PrefetchIterator<K>
extends Object
implements Iterator<K>

An iterator that pre-fetches a number of items in order to calculate the size of the result if possible. This iterator loads at least a number of items, and then tries to load some more items until the timeout is reached or the maximum number of entries are read.

Prefetching is only done when size() is called.

Method Summary

boolean	hasNext()
K	next()
void	remove()
long	size() Get the size if known.

Methods inherited from class java.lang.Object

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

Method Detail

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<K>

next

public K next()

Specified by:

next in interface Iterator<K>

remove

public void remove()

Specified by:

remove in interface Iterator<K>

size

public long size()

Get the size if known. This call might pre-fetch data. The returned value is unknown if the actual size is larger than the number of pre-fetched elements, unless the end of the iterator has been reached already.

Returns:

the size, or -1 if unknown