Handler.java

...
post(new Route("zuora-callout-callback") {
  @Override
  public Object handle(Request request, Response response) {
    logger.info("GOT IT");
    
    for (String v : request.queryParams()) {
      logger.info(v + " " + request.queryParams(v));
    }
    
    logger.info(request.body());
    
    return ok(null); // {"permission": [], "ucode": -1, "result": "ok", "message": "" }
  }
});
...