<?php

/**

 * Zend Framework

 *

 * LICENSE

 *

 * This source file is subject to the new BSD license that is bundled

 * with this package in the file LICENSE.txt.

 * It is also available through the world-wide-web at this URL:

 * http://framework.zend.com/license/new-bsd

 * If you did not receive a copy of the license and are unable to

 * obtain it through the world-wide-web, please send an email

 * to license@zend.com so we can send you a copy immediately.

 *

 * @category   Zend

 * @package    Zend_Search_Lucene

 * @subpackage Analysis

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 * @version    $Id: Common.php 20096 2010-01-06 02:05:09Z bkarwin $

 */

/** Define constant used to provide correct file processing order    */

/** @todo Section should be removed with ZF 2.0 release as obsolete  */

define('ZEND_SEARCH_LUCENE_COMMON_ANALYZER_PROCESSED', true);

/** Zend_Search_Lucene_Analysis_Analyzer */

require_once 'Zend/Search/Lucene/Analysis/Analyzer.php';

/** Zend_Search_Lucene_Analysis_Token */

require_once 'Zend/Search/Lucene/Analysis/Token.php';

/** Zend_Search_Lucene_Analysis_TokenFilter */

require_once 'Zend/Search/Lucene/Analysis/TokenFilter.php';

/**

 * Common implementation of the Zend_Search_Lucene_Analysis_Analyzer interface.

 * There are several standard standard subclasses provided by Zend_Search_Lucene/Analysis

 * subpackage: Zend_Search_Lucene_Analysis_Analyzer_Common_Text, ZSearchHTMLAnalyzer, ZSearchXMLAnalyzer.

 *

 * @todo ZSearchHTMLAnalyzer and ZSearchXMLAnalyzer implementation

 *

 * @category   Zend

 * @package    Zend_Search_Lucene

 * @subpackage Analysis

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

abstract class Zend_Search_Lucene_Analysis_Analyzer_Common extends Zend_Search_Lucene_Analysis_Analyzer

{

    /**

     * The set of Token filters applied to the Token stream.

     * Array of Zend_Search_Lucene_Analysis_TokenFilter objects.

     *

     * @var array

     */

    private $_filters = array();

    /**

     * Add Token filter to the Analyzer

     *

     * @param Zend_Search_Lucene_Analysis_TokenFilter $filter

     */

    public function addFilter(Zend_Search_Lucene_Analysis_TokenFilter $filter)

    {

        $this->_filters[] = $filter;

    }

    /**

     * Apply filters to the token. Can return null when the token was removed.

     *

     * @param Zend_Search_Lucene_Analysis_Token $token

     * @return Zend_Search_Lucene_Analysis_Token

     */

    public function normalize(Zend_Search_Lucene_Analysis_Token $token)

    {

        foreach ($this->_filters as $filter) {

            $token = $filter->normalize($token);

            // resulting token can be null if the filter removes it

            if ($token === null) {

                return null;

            }

        }

        return $token;

    }

}