ning/killbill — comment on commit 848d61f2efa2e158c7f1a43ec6dee89617700416
File: entitlement/src/main/java/com/ning/billing/entitlement/api/user/Subscription.java line 101
By tomdz:

Sure, I just commented because you sort-of asked why static is evil. Also worth pointing out that whether something is a singleton or not is somewhat orthogonal to shared state. Put differently, singletons don't save you from having to deal with concurrent access to the state nor do they make it necessarily harder.