protected function _parseUri($schemeSpecific)
    {
        // High-level decomposition parser
        $pattern = '~^((//)([^/?#]*))([^?#]*)(\?([^#]*))?(#(.*))?$~';
        $status  = @preg_match($pattern, $schemeSpecific, $matches);
        if ($status === false) {
            require_once 'Zend/Uri/Exception.php';
            throw new Zend_Uri_Exception('Internal error: scheme-specific decomposition failed');
        }

        // Failed decomposition; no further processing needed
        if ($status === false) {
            return;
        }

        // Save URI components that need no further decomposition
        $this->_path     = isset($matches[4]) === true ? $matches[4] : '';
        $this->_query    = isset($matches[6]) === true ? $matches[6] : '';
        $this->_fragment = isset($matches[8]) === true ? $matches[8] : '';

        // Additional decomposition to get username, password, host, and port
        $combo   = isset($matches[3]) === true ? $matches[3] : '';
        $pattern = '~^(([^:@]*)(:([^@]*))?@)?([^:]+)(:(.*))?$~';
        $status  = @preg_match($pattern, $combo, $matches);
        if ($status === false) {
            require_once 'Zend/Uri/Exception.php';
            throw new Zend_Uri_Exception('Internal error: authority decomposition failed');
        }

        // Failed decomposition; no further processing needed
        if ($status === false) {
            return;
        }

        // Save remaining URI components
        $this->_username = isset($matches[2]) === true ? $matches[2] : '';
        $this->_password = isset($matches[4]) === true ? $matches[4] : '';
        $this->_host     = isset($matches[5]) === true ? $matches[5] : '';
        $this->_port     = isset($matches[7]) === true ? $matches[7] : '';

    }