File size: 3.19Kb
<?php
/**
* Zend Framework (http://framework.zend.com/)
*
* @link http://github.com/zendframework/zf2 for the canonical source repository
* @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
* @package Zend_Search
*/
namespace ZendSearch\Lucene\Index;
use ZendSearch\Lucene;
/**
* A Term represents a word from text. This is the unit of search. It is
* composed of two elements, the text of the word, as a string, and the name of
* the field that the text occured in, an interned string.
*
* Note that terms may represent more than words from text fields, but also
* things like dates, email addresses, urls, etc.
*
* @category Zend
* @package Zend_Search_Lucene
* @subpackage Index
*/
class Term
{
/**
* Field name or field number (depending from context)
*
* @var mixed
*/
public $field;
/**
* Term value
*
* @var string
*/
public $text;
/**
* Object constructor
*/
public function __construct($text, $field = null)
{
$this->field = ($field === null)? Lucene\Lucene::getDefaultSearchField() : $field;
$this->text = $text;
}
/**
* Returns term key
*
* @return string
*/
public function key()
{
return $this->field . chr(0) . $this->text;
}
/**
* Get term prefix
*
* @param string $str
* @param integer $length
* @return string
*/
public static function getPrefix($str, $length)
{
/**
* @todo !!!!!!! use mb_string or iconv functions if they are available
*/
$prefixBytes = 0;
$prefixChars = 0;
while (isset($str[$prefixBytes]) && $prefixChars < $length) {
$charBytes = 1;
if ((ord($str[$prefixBytes]) & 0xC0) == 0xC0) {
$charBytes++;
if (ord($str[$prefixBytes]) & 0x20 ) {
$charBytes++;
if (ord($str[$prefixBytes]) & 0x10 ) {
$charBytes++;
}
}
}
if (! isset($str[$prefixBytes + $charBytes - 1])) {
// wrong character
break;
}
$prefixChars++;
$prefixBytes += $charBytes;
}
return substr($str, 0, $prefixBytes);
}
/**
* Get UTF-8 string length
*
* @param string $str
* @return string
*/
public static function getLength($str)
{
$bytes = 0;
$chars = 0;
while ($bytes < strlen($str)) {
$charBytes = 1;
if ((ord($str[$bytes]) & 0xC0) == 0xC0) {
$charBytes++;
if (ord($str[$bytes]) & 0x20 ) {
$charBytes++;
if (ord($str[$bytes]) & 0x10 ) {
$charBytes++;
}
}
}
if ($bytes + $charBytes > strlen($str)) {
// wrong character
break;
}
$chars++;
$bytes += $charBytes;
}
return $chars;
}
}