[infinispan-dev] Ideas for locking improvements

[Manik Surtani]

On 9 Jun 2011, at 20:31, Mircea Markus wrote:

>> And what happens if the object's hashcode is not overridden?  Or if a user-defined hashcode is poor and returns the same value for 2 keys?
> In that situation user can plug-in it's own function. I rely on object's hash only if user hasn't introduced his own value. If user doesn't do that and object's native haschode is used then optimisation does not bring any benefit.

I don't think you can do that - you can't force a user to provide a key comparator (you need a sensible default), nor can you ever rely on object.hashcode - even as a fallback - since the result of object.hashcode is different on each different JVM.  It's not that it doesn't bring any benefit, it breaks one of the invariants of the design.  :-)

--
Manik Surtani
manik at jboss.org
twitter.com/maniksurtani

Lead, Infinispan
http://www.infinispan.org