Cache entry expiration?

[John Moore]

I've implemented Cache and CacheManager using Redis. Am I right in 
thinking that Shiro handles all issues to do with cache expiration and 
that I shouldn't automatically expire the cache entries in Redis myself? 
I deduced this from looking at the EHCache implementation. Please 
correct me if I'm wrong. I'll probably still expire the entries after 
say 24 hours, to avoid clogging up the db with orphaned items, unless 
there's a compelling reason not to do this.