protected void cache(Session session, Serializable sessionId, Cache<Serializable, Session> cache) {
        cache.put(sessionId, session);
    }
Caches the specified session in the given cache under the key of {@code sessionId}.  This implementation
simply calls {@code cache.put(sessionId,session)} and can be overridden for custom behavior.

@param session   the session to cache
@param sessionId the id of the session, expected to be the cache key.
@param cache     the cache to store the session
core/src/main/java/org/apache/shiro/session/mgt/eis/CachingSessionDAO.java