text: <?php
  /*
   *  $Id$
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   *
   * This software consists of voluntary contributions made by many individuals
   * and is licensed under the LGPL. For more information, see
   * <http://www.doctrine-project.org>.
   */
  
  /**
   * Doctrine_Query_Filter_Chain
   *
   * @package     Doctrine
   * @subpackage  Query
   * @license     http://www.opensource.org/licenses/lgpl-license.php LGPL
   * @link        www.doctrine-project.org
   * @since       1.0
   * @version     $Revision$
   * @author      Konsta Vesterinen <kvesteri@cc.hut.fi>
   */
  class Doctrine_Query_Filter_Chain
  {
      /**
       * @var array $_filters         an array of Doctrine_Query_Filter objects
       */
      protected $_filters = array();
  
      /**
       * add
       *
       * @param Doctrine_Query_Filter $filter
       * @return void
       */
      public function add(Doctrine_Query_Filter $filter)
      {
          $this->_filters[] = $filter;
      }
  
      /**
       * returns a Doctrine_Query_Filter on success
       * and null on failure
       *
       * @param mixed $key
       * @return mixed
       */
      public function get($key)
      {
          if ( ! isset($this->_filters[$key])) {
              throw new Doctrine_Query_Exception('Unknown filter ' . $key);
          }
          return $this->_filters[$key];
      }
  
      /**
       * set
       *
       * @param mixed $key
       * @param Doctrine_Query_Filter $listener
       * @return void
       */
      public function set($key, Doctrine_Query_Filter $listener)
      {
          $this->_filters[$key] = $listener;
      }
  
      /**
       * preQuery
       *
       * Method for listening the preQuery method of Doctrine_Query and
       * hooking into the query building procedure, doing any custom / specialized
       * query building procedures that are neccessary.
       *
       * @return void
       */
      public function preQuery(Doctrine_Query $query)
      {
          foreach ($this->_filters as $filter) {
              $filter->preQuery($query);
          }
      }
  
      /**
       * postQuery
       *
       * Method for listening the postQuery method of Doctrine_Query and
       * to hook into the query building procedure, doing any custom / specialized
       * post query procedures (for example logging) that are neccessary.
       *
       * @return void
       */
      public function postQuery(Doctrine_Query $query)
      {
          foreach ($this->_filters as $filter) {
              $filter->postQuery($query);
          }
      }
  }