[Aerogear-users] Keycloak - validate token on server

Hello, I am using Aerogear-iOS and I am able to successfully get a JWT from keycloak. Say I pass that JWT to a Java web service (that is not wildfly), is there a way to easily verify the token? The keycloak adapters for undertow and jetty seem beyond my reach. I am using Ninja Framework and the undertow integration does not seem feasible in my time frame. I was hoping to easily validate token on server, but I can't seem to have come across anything. My concern is that I want to disable a user and immediately have them disabled, not wait on expiration in token. I have proposed this question on stack overflow and on the keycloak mailing list with no answers so I was hoping to have some luck here. Thanks.