* @internal documentation reviewed on 18 Mar 2011 by hashar
*/
class BacklinkCache {
+ /** @var ProcessCacheLRU */
+ protected static $cache;
/**
* Multi dimensions array representing batches. Keys are:
/**
* Create a new BacklinkCache
- * @param Title $title : Title object to create a backlink cache for.
+ *
+ * @param Title $title : Title object to create a backlink cache for
*/
- function __construct( $title ) {
+ public function __construct( Title $title ) {
$this->title = $title;
}
+ /**
+ * Create a new BacklinkCache or reuse any existing one.
+ * Currently, only one cache instance can exist; callers that
+ * need multiple backlink cache objects should keep them in scope.
+ *
+ * @param Title $title : Title object to get a backlink cache for
+ * @return BacklinkCache
+ */
+ public static function get( Title $title ) {
+ if ( !self::$cache ) { // init cache
+ self::$cache = new ProcessCacheLRU( 1 );
+ }
+ $dbKey = $title->getPrefixedDBkey();
+ if ( !self::$cache->has( $dbKey, 'obj' ) ) {
+ self::$cache->set( $dbKey, 'obj', new self( $title ) );
+ }
+ return self::$cache->get( $dbKey, 'obj' );
+ }
+
/**
* Serialization handler, diasallows to serialize the database to prevent
* failures after this class is deserialized from cache with dead DB
/**
* Get the field name prefix for a given table
* @param $table String
+ * @throws MWException
* @return null|string
*/
protected function getPrefix( $table ) {
* Get the SQL condition array for selecting backlinks, with a join
* on the page table.
* @param $table String
+ * @throws MWException
* @return array|null
*/
protected function getConditions( $table ) {
default:
$conds = null;
wfRunHooks( 'BacklinkCacheGetConditions', array( $table, $this->title, &$conds ) );
- if( !$conds )
+ if( !$conds ) {
throw new MWException( "Invalid table \"$table\" in " . __CLASS__ );
+ }
}
return $conds;
*/
public function partition( $table, $batchSize ) {
- // 1) try partition cache ...
+ // 1) try partition cache ...
if ( isset( $this->partitionCache[$table][$batchSize] ) ) {
wfDebug( __METHOD__ . ": got from partition cache\n" );
* Partition a DB result with backlinks in it into batches
* @param $res ResultWrapper database result
* @param $batchSize integer
- * @return array @see
+ * @throws MWException
+ * @return array @see
*/
protected function partitionResult( $res, $batchSize ) {
$batches = array();