JCache Cache.invoke does not update entry after initial load

[kdombeck]

If the cache is empty and you call jcache.invoke(key, entryProcessor) it will load the cache with the cache loader but then it will not write the updated entry with the cache writer. The reason is because the EntryProcessorEntry.action is LOADED rather than UPDATED.

Possibly related to #187.

This is currently just a unit test showing the problem, it does not contain a fix. I'm not sure which direction to go for a possible fix.

[ben-manes]

Thanks for the test, again! :)

I'm swamped today, but I'll try to look at this on my way home (PST). I owe people a new release so I should be able to get this out soon. Not sure about the fix yet until we both dig in a bit.

[ben-manes]

hmm.. you are right that this is confusing. I originally followed the reference implementation, but the JSR authors do not consider it good quality. The specification is primarily the interface JavaDoc pasted into sections rather than additional depth.

The right thing is to probably sketch out the scenarios from scratch, using the examples in EntryProcessor's JavaDoc as guidance. I think part of the confusion is that it states Only the net effect of multiple operations has visibility outside of the Entry Processor, but it also states weird things like The first get and the second put only are visible to the ExpiryPolicy which means it isn't entirely flattened out. So I don't know if we can rely on a single state machine, should use a mixture of flags, or a queue of events.

[ben-manes]

The fix passes your test. The lifecycle is still very confusing, so please let me know if you discover other bugs. Adding the simple check of whether the entry was originally present in the cache seems to pass all the tests.

[ben-manes]

Released

[kdombeck]

Works perfectly!! Thank you