/**
* Returns a mapper, based on the $uri and $format
*
* @param string $uri File URI
* @param string $format File format (extension or mime-type) or null
* @return WideImage_Mapper
**/
static function selectMapper($uri, $format = null)
{
$format = self::determineFormat($uri, $format);
if (array_key_exists($format, self::$mappers)) {
return self::$mappers[$format];
}
$mapperClassName = 'WideImage_Mapper_' . $format;
if (!class_exists($mapperClassName, false)) {
$mapperFileName = WideImage::path() . 'Mapper/' . $format . '.php';
if (file_exists($mapperFileName)) {
require_once $mapperFileName;
}
}
if (class_exists($mapperClassName)) {
self::$mappers[$format] = new $mapperClassName();
return self::$mappers[$format];
}
throw new WideImage_UnsupportedFormatException("Format '{$format}' is not supported.");
}
