class DrupalQueue

class DrupalQueue  {
 
 /**
 * Returns the queue object for a given name.
 *
 * The following variables can be set by variable_set or $conf overrides:
 * - queue_class_$name: the class to be used for the queue $name.
 * - queue_default_class: the class to use when queue_class_$name is not
 * defined. Defaults to SystemQueue, a reliable backend using SQL.
 * - queue_default_reliable_class: the class to use when queue_class_$name is
 * not defined and the queue_default_class is not reliable. Defaults to
 * SystemQueue.
 *
 * @param $name
 * Arbitrary string. The name of the queue to work with.
 * @param $reliable
 * TRUE if the ordering of items and guaranteeing every item executes at
 * least once is important, FALSE if scalability is the main concern.
 *
 * @return
 * The queue object for a given name.
 */
 public static function get($name, $reliable = FALSE) {
 static $queues;
 if (!isset($queues[$name])) {
 $class = variable_get ('queue_class_' . $name, NULL);
 if (!$class) {
 $class = variable_get ('queue_default_class', 'SystemQueue');
 }
 $object = new $class($name);
 if ($reliable && !$object instanceof DrupalReliableQueueInterface) {
 $class = variable_get ('queue_default_reliable_class', 'SystemQueue');
 $object = new $class($name);
 }
 $queues[$name] = $object;
 }
 return $queues[$name];
 }
}