title: Spring oauth2 token based authentication
body: <p>I have two queries regarding spring oauth2 - </p>
  
  <p>1) With client crendentials grant type, as part of /oauth/token call, is it possible to validate client id and secret via a remote service call rather than maintaining the client credentials in DB or in memory as the client credentials are maintained in a remote system? If client credentials are maintained in a remote system, can the tokens still be maintained in the my app (in memory or db)?</p>
  
  <p>2) While building a REST back end for mobile/native apps, what kind of grant type should be used so as to be able to generate a unique token for each logged in user such that one logged in user cannot use the token generated for another logged in user? </p>
  
  <p>Regards,
  Jacob</p>