This flag signals that the client that calls an Infinispan Cache operation () which has some kind of return, i.e. java.util.Map#put(Object, Object) (remember that Infinispan's Cache interface extends java.util.Map), the return value (which in the case of java.util.Map#put(Object, Object) represents the previous value) will be ignored by the client application. A typical client application that ignores the return value would use code like this:
In this example, both cache put call are ignoring the return of the put call, which returns the previous value. In other words, when we cache the last login date, we don't care what the previous value was, so this is a great opportunity for the client code to be re-written in this way:
Or even better:
Thanks to such hints, Infinispan caches can behave in a more efficient way and can potentially do operations faster, because work associated with the production of the return value will be skipped. Such work can on occasions involve network calls, or access to persistent cache stores, so by avoiding this work, the cache calls are effectively faster.
In previous Infinispan versions, a similar effect could be achieved with flags with a narrower target and which are considered too brittle for end user consumption such as SKIP_REMOTE_LOOKUP or SKIP_CACHE_LOAD. So, if you're using either of these flags in your Infinispan client codebase, we highly recommend that from Infinispan 5.2.0.Alpha3 you start using IGNORE_RETURN_VALUES instead.Cheers, Galder