Java Auth0 , Creating a Groups key

Question

I am trying to create a groups key in Java Auth0 JWT.

this is my current code below. How do I add a groups key below in Java syntax?

import com.auth0.jwt.JWT;
...
String token = JWT.create()
    .withSubject(jwtTokenRequest.getUsername())
    .withJWTId(jwtId)
    .withIssuedAt(new Date())
    .sign(algorithm);