Here is an insightful note by Mark Miller on how caps fit in statically typed languages or how capability discipline can be discovered within some languages. There are a few links there beginning “http://www.mediacity.com” that are now at “http://cap-lore.com”. I think that the reference to Java documentation is now here.

Here is some important needed and proposed terminology.

I have not found a case where I needed to know if this here RO page key is to the same page as this RW page key. And if I did need to I would weaken the RW key to RO and then compare the two RO keys for equality.