I'm trying to implement Spring OAuth. I'm new to it and I'm trying to understand how it works.
OAuth2RestTemplatewhich automatically fetch it and add to request.
3.a) there is another issue with storing some data on client side. Its about storing clientId, clientSecret on mobile native apps. Android apps code can be reverse engineered quite easily, so anyone can then try to use your oauth app to get token. In those situations its recomennded to use different grant type "password" - check https://aaronparecki.com/2012/07/29/2/oauth2-simplified#other-app-types