includes/libs/ProcessCacheLRU.php

   1 <?php
   2 /**
   3  * Per-process memory cache for storing items.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Cache
  22  */
  23
  24 /**
  25  * Class for process caching individual properties of expiring items
  26  *
  27  * When the key for an entire item is deleted, all properties for it are deleted
  28  *
  29  * @ingroup Cache
  30  * @deprecated Since 1.32 Use MapCacheLRU instead
  31  */
  32 class ProcessCacheLRU {
  33         /** @var MapCacheLRU */
  34         protected $cache;
  35
  36         /**
  37          * @param int $maxKeys Maximum number of entries allowed (min 1).
  38          * @throws UnexpectedValueException When $maxCacheKeys is not an int or =< 0.
  39          */
  40         public function __construct( $maxKeys ) {
  41                 $this->cache = new MapCacheLRU( $maxKeys );
  42         }
  43
  44         /**
  45          * Set a property field for a cache entry.
  46          * This will prune the cache if it gets too large based on LRU.
  47          * If the item is already set, it will be pushed to the top of the cache.
  48          *
  49          * @param string $key
  50          * @param string $prop
  51          * @param mixed $value
  52          * @return void
  53          */
  54         public function set( $key, $prop, $value ) {
  55                 $this->cache->setField( $key, $prop, $value );
  56         }
  57
  58         /**
  59          * Check if a property field exists for a cache entry.
  60          *
  61          * @param string $key
  62          * @param string $prop
  63          * @param float $maxAge Ignore items older than this many seconds (since 1.21)
  64          * @return bool
  65          */
  66         public function has( $key, $prop, $maxAge = 0.0 ) {
  67                 return $this->cache->hasField( $key, $prop, $maxAge );
  68         }
  69
  70         /**
  71          * Get a property field for a cache entry.
  72          * This returns null if the property is not set.
  73          * If the item is already set, it will be pushed to the top of the cache.
  74          *
  75          * @param string $key
  76          * @param string $prop
  77          * @return mixed
  78          */
  79         public function get( $key, $prop ) {
  80                 return $this->cache->getField( $key, $prop );
  81         }
  82
  83         /**
  84          * Clear one or several cache entries, or all cache entries.
  85          *
  86          * @param string|array|null $keys
  87          * @return void
  88          */
  89         public function clear( $keys = null ) {
  90                 $this->cache->clear( $keys );
  91         }
  92
  93         /**
  94          * Resize the maximum number of cache entries, removing older entries as needed
  95          *
  96          * @param int $maxKeys
  97          * @return void
  98          * @throws UnexpectedValueException
  99          */
 100         public function resize( $maxKeys ) {
 101                 $this->cache->setMaxSize( $maxKeys );
 102         }
 103
 104         /**
 105          * Get cache size
 106          * @return int
 107          */
 108         public function getSize() {
 109                 return $this->cache->getMaxSize();
 110         }
 111 }