git.roojs.org Git - web.mtrack/blob - inc/lib/Zend/Search/Lucene/TermStreamsPriorityQueue.php

   1 <?php\r
   2 /**\r
   3  * Zend Framework\r
   4  *\r
   5  * LICENSE\r
   6  *\r
   7  * This source file is subject to the new BSD license that is bundled\r
   8  * with this package in the file LICENSE.txt.\r
   9  * It is also available through the world-wide-web at this URL:\r
  10  * http://framework.zend.com/license/new-bsd\r
  11  * If you did not receive a copy of the license and are unable to\r
  12  * obtain it through the world-wide-web, please send an email\r
  13  * to license@zend.com so we can send you a copy immediately.\r
  14  *\r
  15  * @category   Zend\r
  16  * @package    Zend_Search_Lucene\r
  17  * @subpackage Index\r
  18  * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)\r
  19  * @license    http://framework.zend.com/license/new-bsd     New BSD License\r
  20  * @version    $Id: TermStreamsPriorityQueue.php 16971 2009-07-22 18:05:45Z mikaelkael $\r
  21  */\r
  22 \r
  23 /** Zend_Search_Lucene_Index_TermsStream_Interface */\r
  24 require_once 'Zend/Search/Lucene/Index/TermsStream/Interface.php';\r
  25 \r
  26 /** Zend_Search_Lucene_Index_TermsPriorityQueue */\r
  27 require_once 'Zend/Search/Lucene/Index/TermsPriorityQueue.php';\r
  28 \r
  29 \r
  30 /**\r
  31  * @category   Zend\r
  32  * @package    Zend_Search_Lucene\r
  33  * @subpackage Index\r
  34  * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)\r
  35  * @license    http://framework.zend.com/license/new-bsd     New BSD License\r
  36  */\r
  37 class Zend_Search_Lucene_TermStreamsPriorityQueue implements Zend_Search_Lucene_Index_TermsStream_Interface\r
  38 {\r
  39         /**\r
  40          * Array of term streams (Zend_Search_Lucene_Index_TermsStream_Interface objects)\r
  41          *\r
  42          * @var array\r
  43          */\r
  44         protected $_termStreams;\r
  45 \r
  46         /**\r
  47      * Terms stream queue\r
  48      *\r
  49      * @var Zend_Search_Lucene_Index_TermsPriorityQueue\r
  50      */\r
  51     protected $_termsStreamQueue = null;\r
  52 \r
  53     /**\r
  54      * Last Term in a terms stream\r
  55      *\r
  56      * @var Zend_Search_Lucene_Index_Term\r
  57      */\r
  58     protected $_lastTerm = null;\r
  59 \r
  60 \r
  61     /**\r
  62      * Object constructor\r
  63      *\r
  64      * @param array $termStreams  array of term streams (Zend_Search_Lucene_Index_TermsStream_Interface objects)\r
  65      */\r
  66         public function __construct(array $termStreams)\r
  67         {\r
  68                 $this->_termStreams = $termStreams;\r
  69 \r
  70                 $this->resetTermsStream();\r
  71         }\r
  72 \r
  73         /**\r
  74      * Reset terms stream.\r
  75      */\r
  76     public function resetTermsStream()\r
  77     {\r
  78         $this->_termsStreamQueue = new Zend_Search_Lucene_Index_TermsPriorityQueue();\r
  79 \r
  80         foreach ($this->_termStreams as $termStream) {\r
  81             $termStream->resetTermsStream();\r
  82 \r
  83             // Skip "empty" containers\r
  84             if ($termStream->currentTerm() !== null) {\r
  85                 $this->_termsStreamQueue->put($termStream);\r
  86             }\r
  87         }\r
  88 \r
  89         $this->nextTerm();\r
  90     }\r
  91 \r
  92     /**\r
  93      * Skip terms stream up to specified term preffix.\r
  94      *\r
  95      * Prefix contains fully specified field info and portion of searched term\r
  96      *\r
  97      * @param Zend_Search_Lucene_Index_Term $prefix\r
  98      */\r
  99     public function skipTo(Zend_Search_Lucene_Index_Term $prefix)\r
 100     {\r
 101         $termStreams = array();\r
 102 \r
 103         while (($termStream = $this->_termsStreamQueue->pop()) !== null) {\r
 104             $termStreams[] = $termStream;\r
 105         }\r
 106 \r
 107         foreach ($termStreams as $termStream) {\r
 108             $termStream->skipTo($prefix);\r
 109 \r
 110             if ($termStream->currentTerm() !== null) {\r
 111                 $this->_termsStreamQueue->put($termStream);\r
 112             }\r
 113         }\r
 114 \r
 115         $this->nextTerm();\r
 116     }\r
 117 \r
 118     /**\r
 119      * Scans term streams and returns next term\r
 120      *\r
 121      * @return Zend_Search_Lucene_Index_Term|null\r
 122      */\r
 123     public function nextTerm()\r
 124     {\r
 125         while (($termStream = $this->_termsStreamQueue->pop()) !== null) {\r
 126             if ($this->_termsStreamQueue->top() === null ||\r
 127                 $this->_termsStreamQueue->top()->currentTerm()->key() !=\r
 128                             $termStream->currentTerm()->key()) {\r
 129                 // We got new term\r
 130                 $this->_lastTerm = $termStream->currentTerm();\r
 131 \r
 132                 if ($termStream->nextTerm() !== null) {\r
 133                     // Put segment back into the priority queue\r
 134                     $this->_termsStreamQueue->put($termStream);\r
 135                 }\r
 136 \r
 137                 return $this->_lastTerm;\r
 138             }\r
 139 \r
 140             if ($termStream->nextTerm() !== null) {\r
 141                 // Put segment back into the priority queue\r
 142                 $this->_termsStreamQueue->put($termStream);\r
 143             }\r
 144         }\r
 145 \r
 146         // End of stream\r
 147         $this->_lastTerm = null;\r
 148 \r
 149         return null;\r
 150     }\r
 151 \r
 152     /**\r
 153      * Returns term in current position\r
 154      *\r
 155      * @return Zend_Search_Lucene_Index_Term|null\r
 156      */\r
 157     public function currentTerm()\r
 158     {\r
 159         return $this->_lastTerm;\r
 160     }\r
 161 \r
 162     /**\r
 163      * Close terms stream\r
 164      *\r
 165      * Should be used for resources clean up if stream is not read up to the end\r
 166      */\r
 167     public function closeTermsStream()\r
 168     {\r
 169         while (($termStream = $this->_termsStreamQueue->pop()) !== null) {\r
 170             $termStream->closeTermsStream();\r
 171         }\r
 172 \r
 173         $this->_termsStreamQueue = null;\r
 174         $this->_lastTerm         = null;\r
 175     }\r
 176 }\r