A Sneak Peek at StableValue and SegmentMapper in Java

[@thomasdarimont]

StableValue will be one of the true gems in the upcoming JDK versions!

[@chu121su12]

I made userland implementation based on the draft jep

[@xozzy7809]

Beauty of simplicity

[@gudenau]

Man these Java changes are super cool, I can't wait to use them when they come out!

[@NikitaKovalenko-j7c]

Excellent talk! Thank you

[@jtirex]

Have been doing lots of ffm stuff for c interop - really looking forward to the segmentmapper, that looks great

[@Sm0keySa1m0n]

Will stable values provide performance benefits for MethodHandle similar to putting one in a static final field?

[@delanym]

I use a CAS "Thunk" class extensively but it will go when this StableValue arrives

[@mekud]

please use IDEA's presentation mode. please.

[@krellin]

nice, actual improvements to the language

[@krellin]

anyone knows what zsh config is that? i like it a lot

[@TnTorciv]

33:35 "You can't do set accessible to and then update the field that will throw an exception just that it will do if you do the same thing in record. You can't get the offset for the field using unsafe because that will throw an exception but there are ways to do it but I will not tell you how" 🤣🤣🤣

[@duckydude20]

want to see what kotlin does with all these jvm features...

[@rushslowly9450]

or Scala, especially with value classes it will get interesting to see how Scala responds

[@evgheniemelianov3594]

Why not using Optional instead of StableValue? It seems to have the same semantics?

[@HonestAuntyElle]

This is cool, but something that always confuses me, is a lot of stuff that would be key words in another language, are "just idk classes and methods" in java. It makes it difficult to know if something has special behaviour in the VM.

[@kaqqao]

Never understood why you'd want a keyword. You can't later add a method to a keyword, you can't parameterize it, inherit it, or even deprecate it cleanly. And you can do all those things to a class just fine. So why have a keyword (and an ever growing syntax), when a regular old class will suffice? As for knowing about the special treatment by the VM, these classes aren't something you'll ever accidentally use. You'll seek them out only if and when you need a specific optimization. In all other cases, you really don't have to even be aware of their special properties. A StableSupplier is just a supplier after all.

[@freemanlau-yl8nq]

Just call it ‘Once’ :)

[@HonestAuntyElle]

It feels a lot like memoization and lazy loading.

[@31redorange08]

OnceOrNever

[@HonestAuntyElle]

Love the concept, hate the API. I want to be able to use this as much as possible by default, but it feels unwieldy, which will only result in people doing hotspot performance improvements using it.

Why do not add a language construct like kotlin's lazy?

[@Ethesen]

@28:10, @31:30

@@Ethesen Thank you! I was not paying attention at the end of the video... :(

[@cod3r1337]

Cool, did they just reinvent Kotlin's lazy delegate?

[@markepshtein3735]

kotlin lazy provides ability to control how many times lambda can be invoked. Also delegate feature makes it easy to use. StableValue came after kotlin lazy but looks uglier.

[@krellin]

real OOP = a lot of singletones what people actually do is Class Oriented Programming...

[@forsakensandor]

Eh, maybe people's perception of what's maintainable has evolved? Full OOP was never a silver bullet but Java supports it just fine. With new additions, it also supports more reasonable paradigms..

[@FlaviusAspra]

StableValue is anti-oop. But the real sad part: people don't see it.