classes/class.ilObjectDataCache.php

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<?php
/*
        +-----------------------------------------------------------------------------+
        | ILIAS open source                                                           |
        +-----------------------------------------------------------------------------+
        | Copyright (c) 1998-2001 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. |
        +-----------------------------------------------------------------------------+
*/

class ilObjectDataCache
{
        var $db = null;
        var $reference_cache = array();
        var $object_data_cache = array();

        function ilObjectDataCache()
        {
                global $ilDB;

                $this->db =& $ilDB;
        }

        function deleteCachedEntry($a_obj_id)
        {
                unset($this->object_data_cache[$a_obj_id]);
        }

        function lookupObjId($a_ref_id)
        {
                if(!$this->__isReferenceCached($a_ref_id))
                {
                        $obj_id = $this->__storeReference($a_ref_id);
                        $this->__storeObjectData($obj_id);
                }
                return (int) @$this->reference_cache[$a_ref_id];
        }

        function lookupTitle($a_obj_id)
        {
                if(!$this->__isObjectCached($a_obj_id))
                {
                        $this->__storeObjectData($a_obj_id);
                }
                return @$this->object_data_cache[$a_obj_id]['title'];
        }

        function lookupType($a_obj_id)
        {
                if(!$this->__isObjectCached($a_obj_id))
                {
                        $this->__storeObjectData($a_obj_id);
                }
                return @$this->object_data_cache[$a_obj_id]['type'];
        }

        function lookupOwner($a_obj_id)
        {
                if(!$this->__isObjectCached($a_obj_id))
                {
                        $this->__storeObjectData($a_obj_id);
                }
                return @$this->object_data_cache[$a_obj_id]['owner'];
        }

        function lookupDescription($a_obj_id)
        {
                if(!$this->__isObjectCached($a_obj_id))
                {
                        $this->__storeObjectData($a_obj_id);
                }
                return @$this->object_data_cache[$a_obj_id]['description'];
        }

        function lookupLastUpdate($a_obj_id)
        {
                if(!$this->__isObjectCached($a_obj_id))
                {
                        $this->__storeObjectData($a_obj_id);
                }
                return @$this->object_data_cache[$a_obj_id]['last_update'];
        }
        // PRIVATE

        function __isReferenceCached($a_ref_id)
        {
                #return false;
                #static $cached = 0;
                #static $not_cached = 0;

                if(@$this->reference_cache[$a_ref_id])
                {
                        #echo "Reference ". ++$cached ."cached<br>";
                        return true;
                }
                #echo "Reference ". ++$not_cached ." not cached<br>";
                return false;
                
        }

        function __isObjectCached($a_obj_id)
        {
                static $cached = 0;
                static $not_cached = 0;
                        

                if(@$this->object_data_cache[$a_obj_id])
                {
                        #echo "Object ". ++$cached ."cached<br>";
                        return true;
                }
                #echo "Object ". ++$not_cached ." not cached<br>";
                return false;
        }


        function __storeReference($a_ref_id)
        {
                global $ilDB;
                
                $query = "SELECT obj_id FROM object_reference WHERE ref_id = ".$ilDB->quote($a_ref_id);
                $res = $this->db->query($query);
                while($row = $res->fetchRow(DB_FETCHMODE_ASSOC))
                {
                        $this->reference_cache[$a_ref_id] = $row['obj_id'];
                }
                return (int) @$this->reference_cache[$a_ref_id];
        }

        function __storeObjectData($a_obj_id)
        {
                $query = "SELECT * FROM object_data WHERE obj_id = '".$a_obj_id."'";
                $res = $this->db->query($query);
                while($row = $res->fetchRow(DB_FETCHMODE_OBJECT))
                {
                        $this->object_data_cache[$a_obj_id]['title'] = $row->title;
                        $this->object_data_cache[$a_obj_id]['description'] = $row->description;
                        $this->object_data_cache[$a_obj_id]['type'] = $row->type;
                        $this->object_data_cache[$a_obj_id]['owner'] = $row->owner;
                        $this->object_data_cache[$a_obj_id]['last_update'] = $row->last_update;

                }
                return true;
        }
}
?>