silverstripe-docsviewer/thirdparty/Zend/Search/Lucene/TermStreamsPriorityQueue.php
2011-07-01 13:19:35 +12:00

177 lines
4.9 KiB
PHP
Executable File

<?php
/**
* Zend Framework
*
* LICENSE
*
* This source file is subject to the new BSD license that is bundled
* with this package in the file LICENSE.txt.
* It is also available through the world-wide-web at this URL:
* http://framework.zend.com/license/new-bsd
* If you did not receive a copy of the license and are unable to
* obtain it through the world-wide-web, please send an email
* to license@zend.com so we can send you a copy immediately.
*
* @category Zend
* @package Zend_Search_Lucene
* @subpackage Index
* @copyright Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
* @version $Id: TermStreamsPriorityQueue.php 20096 2010-01-06 02:05:09Z bkarwin $
*/
/** Zend_Search_Lucene_Index_TermsStream_Interface */
require_once 'Zend/Search/Lucene/Index/TermsStream/Interface.php';
/**
* @category Zend
* @package Zend_Search_Lucene
* @subpackage Index
* @copyright Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
*/
class Zend_Search_Lucene_TermStreamsPriorityQueue implements Zend_Search_Lucene_Index_TermsStream_Interface
{
/**
* Array of term streams (Zend_Search_Lucene_Index_TermsStream_Interface objects)
*
* @var array
*/
protected $_termStreams;
/**
* Terms stream queue
*
* @var Zend_Search_Lucene_Index_TermsPriorityQueue
*/
protected $_termsStreamQueue = null;
/**
* Last Term in a terms stream
*
* @var Zend_Search_Lucene_Index_Term
*/
protected $_lastTerm = null;
/**
* Object constructor
*
* @param array $termStreams array of term streams (Zend_Search_Lucene_Index_TermsStream_Interface objects)
*/
public function __construct(array $termStreams)
{
$this->_termStreams = $termStreams;
$this->resetTermsStream();
}
/**
* Reset terms stream.
*/
public function resetTermsStream()
{
/** Zend_Search_Lucene_Index_TermsPriorityQueue */
require_once 'Zend/Search/Lucene/Index/TermsPriorityQueue.php';
$this->_termsStreamQueue = new Zend_Search_Lucene_Index_TermsPriorityQueue();
foreach ($this->_termStreams as $termStream) {
$termStream->resetTermsStream();
// Skip "empty" containers
if ($termStream->currentTerm() !== null) {
$this->_termsStreamQueue->put($termStream);
}
}
$this->nextTerm();
}
/**
* Skip terms stream up to specified term preffix.
*
* Prefix contains fully specified field info and portion of searched term
*
* @param Zend_Search_Lucene_Index_Term $prefix
*/
public function skipTo(Zend_Search_Lucene_Index_Term $prefix)
{
$termStreams = array();
while (($termStream = $this->_termsStreamQueue->pop()) !== null) {
$termStreams[] = $termStream;
}
foreach ($termStreams as $termStream) {
$termStream->skipTo($prefix);
if ($termStream->currentTerm() !== null) {
$this->_termsStreamQueue->put($termStream);
}
}
$this->nextTerm();
}
/**
* Scans term streams and returns next term
*
* @return Zend_Search_Lucene_Index_Term|null
*/
public function nextTerm()
{
while (($termStream = $this->_termsStreamQueue->pop()) !== null) {
if ($this->_termsStreamQueue->top() === null ||
$this->_termsStreamQueue->top()->currentTerm()->key() !=
$termStream->currentTerm()->key()) {
// We got new term
$this->_lastTerm = $termStream->currentTerm();
if ($termStream->nextTerm() !== null) {
// Put segment back into the priority queue
$this->_termsStreamQueue->put($termStream);
}
return $this->_lastTerm;
}
if ($termStream->nextTerm() !== null) {
// Put segment back into the priority queue
$this->_termsStreamQueue->put($termStream);
}
}
// End of stream
$this->_lastTerm = null;
return null;
}
/**
* Returns term in current position
*
* @return Zend_Search_Lucene_Index_Term|null
*/
public function currentTerm()
{
return $this->_lastTerm;
}
/**
* Close terms stream
*
* Should be used for resources clean up if stream is not read up to the end
*/
public function closeTermsStream()
{
while (($termStream = $this->_termsStreamQueue->pop()) !== null) {
$termStream->closeTermsStream();
}
$this->_termsStreamQueue = null;
$this->_lastTerm = null;
}
}