我正在研究来自 Google API 客户端的代码,以便能够为 Google 组中的用户提供服务,但我在代码中有两个问题。
例子
/**
* Exchange an authorization code for OAuth 2.0 credentials.
*
* @param authorizationCode Authorization code to exchange for OAuth 2.0
* credentials.
* @return OAuth 2.0 credentials.
* @throws CodeExchangeException An error occurred.
*/
static Credential exchangeCode(String authorizationCode)
throws CodeExchangeException {
try {
GoogleAuthorizationCodeFlow flow = getFlow();
GoogleTokenResponse response =
flow.newTokenRequest(authorizationCode).setRedirectUri(REDIRECT_URI).execute();
return flow.createAndStoreCredential(response, null);
} catch (IOException e) {
System.err.println("An error occurred: " + e);
throw new CodeExchangeException(null);
}
}
片段显示:
flow.createAndStoreCredential (response, null);
- 它究竟是做什么的?存储在数据库中还是内存中?什么是数据库?
- 其中 null 作为参数,可以传递一个 userId。如何让这个用户 ID 作为参数传递?
来源:https ://developers.google.com/drive/training/drive-apps/auth/credentials