Unclosed session detected errors in log

We are seeing this error in the logs. I've seen that the vendor who wrote code for us is using something like this

 ResourceResolver resourceResolver = request.getResourceResolver();
        QueryBuilder queryBuilder = resourceResolver.adaptTo(QueryBuilder.class);
        Session session = resourceResolver.adaptTo(Session.class);

Does this session need to be closed in finally as well os it's only when we try to get administrative session that we need to correctly close it?

Any links for best practices while writing servlets and using sessions would be appreciated.