class.ilLuceneSearcher.php

Go to the documentation of this file.

<?php
/*
        +-----------------------------------------------------------------------------+
        | ILIAS open source                                                           |
        +-----------------------------------------------------------------------------+
        | Copyright (c) 1998-2006 ILIAS open source, University of Cologne            |
        |                                                                             |
        | This program is free software; you can redistribute it and/or               |
        | modify it under the terms of the GNU General Public License                 |
        | as published by the Free Software Foundation; either version 2              |
        | of the License, or (at your option) any later version.                      |
        |                                                                             |
        | This program is distributed in the hope that it will be useful,             |
        | but WITHOUT ANY WARRANTY; without even the implied warranty of              |
        | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               |
        | GNU General Public License for more details.                                |
        |                                                                             |
        | You should have received a copy of the GNU General Public License           |
        | along with this program; if not, write to the Free Software                 |
        | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA. |
        +-----------------------------------------------------------------------------+
*/

include_once './Services/Search/classes/Lucene/class.ilLuceneSearchResult.php';

class ilLuceneSearcher
{
        private static $instance = null;
        
        private $query_parser = null;
        private $result = null;
        private $highlighter = null;
        private $page_number = 1;

        private function __construct($qp)
        {
                $this->result = new ilLuceneSearchResult();
                $this->result->setCallback(array($this,'nextResultPage'));
                $this->query_parser = $qp;
        }
        
        public static function getInstance(ilLuceneQueryParser $qp)
        {
                if(self::$instance)
                {
                        return self::$instance;
                }
                return self::$instance = new ilLuceneSearcher($qp);
        }
        
        public function search()
        {
                $this->performSearch();
        }
        
        public function highlight($a_obj_ids)
        {
                global $ilBench,$ilSetting, $ilLog;

                include_once './Services/Search/classes/Lucene/class.ilLuceneHighlighterResultParser.php';
                
                // TODO error handling
                if(!$this->query_parser->getQuery())
                {
                        return;
                }
                
                // Search in combined index
                $ilBench->start('Lucene','SearchHighlight');
                try
                {
                        include_once './Services/WebServices/RPC/classes/class.ilRpcClientFactory.php';
                        $res = ilRpcClientFactory::factory('RPCSearchHandler')->highlight(
                                CLIENT_ID.'_'.$ilSetting->get('inst_id',0),
                                $a_obj_ids,
                                $this->query_parser->getQuery()
                                );
                }
                catch(XML_RPC2_FaultException $e)
                {
                        // TODO: better error handling
                        $ilLog->write(__METHOD__.': '.$e->getMessage());
                        return new ilLuceneHighlighterResultParser();
                }
                catch(Exception $e)
                {
                        $ilLog->write(__METHOD__.': '.$e->getMessage());
                        return new ilLuceneHighlighterResultParser();
                }
                $ilBench->stop('Lucene','SearchHighlight');

                $ilBench->start('Lucene','SearchHighlightParser');
                include_once './Services/Search/classes/Lucene/class.ilLuceneHighlighterResultParser.php';
                $this->highlighter = new ilLuceneHighlighterResultParser();
                $this->highlighter->setResultString($res);
                $this->highlighter->parse();
                $ilBench->stop('Lucene','SearchHighlightParser');

                return $this->highlighter;
        }
        
        public function nextResultPage()
        {
                $this->page_number++;
                $this->performSearch();
        }
        
        public function getHighlighter()
        {
                return $this->highlighter;       
        }
        
        public function getResult()
        {
                if($this->result instanceof ilLuceneSearchResult)
                {
                        return $this->result;
                }
                // TODO Error handling
        }
        
        public function getPageNumber()
        {
                return $this->page_number;
        }
        
        protected function performSearch()
        {
                global $ilBench,$ilSetting, $ilLog;

                // TODO error handling
                if(!$this->query_parser->getQuery())
                {
                        return;
                }
                $ilBench->start('Lucene','SearchCombinedIndex');
                try
                {
                        include_once './Services/WebServices/RPC/classes/class.ilRpcClientFactory.php';
                        $res = ilRpcClientFactory::factory('RPCSearchHandler')->search(
                                CLIENT_ID.'_'.$ilSetting->get('inst_id',0),
                                (string) $this->query_parser->getQuery(),
                                $this->getPageNumber()
                        );
                }
                catch(XML_RPC2_FaultException $e)
                {
                        // TODO: better error handling
                        $ilBench->stop('Lucene','SearchCombinedIndex');
                        $ilLog->write(__METHOD__.': '.$e->getMessage());
                        return;
                }
                catch(Exception $e)
                {
                        $ilBench->stop('Lucene','SearchCombinedIndex');
                        $ilLog->write(__METHOD__.': '.$e->getMessage());
                        return;
                }
                $ilBench->stop('Lucene','SearchCombinedIndex');         

                
                // Parse results
                $ilBench->start('Lucene','ParseSearchResult');
                include_once './Services/Search/classes/Lucene/class.ilLuceneSearchResultParser.php';
                $parser = new ilLuceneSearchResultParser($res);
                $parser->parse($this->result);
                $ilBench->stop('Lucene','ParseSearchResult');
                return;
        }
}
?>