Method existing

/**
 * Get a list of the available administrator language items.
 *
 * @param   boolean  $all        True to include All (*)
 * @param   boolean  $translate  True to translate All
 *
 * @return  array
 *
 * @since   3.8.0
 */
public static function existing($all = false, $translate = false)
{
    if (empty(static::$items)) {
        $languages = array();
        $admin_languages = LanguageHelper::getKnownLanguages(JPATH_ADMINISTRATOR);
        foreach ($admin_languages as $tag => $language) {
            $languages[$tag] = $language['nativeName'];
        }
        ksort($languages);
        static::$items = $languages;
    }
    if ($all) {
        $all_option = array(new CMSObject(array('value' => '*', 'text' => $translate ? Text::alt('JALL', 'language') : 'JALL_LANGUAGE')));
        return array_merge($all_option, static::$items);
    } else {
        return static::$items;
    }
}