Use Both JWT and Opaque Access Tokens With Spring Boot

How can one validate OAuth 2.0 access tokens? This question frequently comes up — along with the topic of validating JSON Web Tokens (JWT) based access tokens— however, this is NOT part of the OAuth 2.0 specification. JWTs are used so commonly that Spring Security supported them before adding support for remotely validating tokens. 

This article will introduce how to build a simple application that utilizes both types of validation.