GarbageCollector.php

<?php
class Dsao_GarbageCollector
{
  protected $_items;

  public function __construct(array $items)
  {
    $this->_items = array();

    foreach ($items as $item)
    {
      $this->_items[] = new Dsao_GarbageCollector_Item($item);
    }
  }

  public function addItem($method, $object = null, $probability = 10)
  {
    $this->_items[] =
      new Dsao_GarbageCollector_Item($method, $object, $probability);

    return $this;
  }

  public function run()
  {
    foreach ($this->_items as $item)
    {
      $item->run();
    }

    return $this;
  }
}