function __construct($url, $params = array(), $method = 'POST')
{
if (!isset($params['oauth_version'])) {
$params['oauth_version'] = self::VERSION;
}
if (!isset($params['oauth_nonce'])) {
$params['oauth_nonce'] = self::_generateNonce();
}
if (!isset($params['oauth_timestamp'])) {
$params['oauth_timestamp'] = time();
}
$this->_params = $params;
$this->_url = $url;
$this->_method = $method;
}