Hacker News: joe_mwangi

New comment by joe_mwangi in "Go Concurrency Distilled"

joe_mwangi — Sun, 27 Sep 2026 18:46:14 +0000

Trust me. That's a common argument used when java introduces new features. Wait you see the same argument once value classes come to jdk 28.

New comment by joe_mwangi in "Java 27"

joe_mwangi — Tue, 15 Sep 2026 21:55:14 +0000

Yes.. lol. The biggest argument now is Kotlin having nullness by default in the language. Just check around the comment section. Now java is planning to have them which will further help jvm to optimise for performance. Not sure what the next argument will be after.

New comment by joe_mwangi in "Java 27"

joe_mwangi — Tue, 15 Sep 2026 19:46:02 +0000

Really? I don't thinks so. There is a reason JEP 539 is in preview. There is a reason internal annotations exists in current valhalla jdk prototype and upcoming java 28 such as @jdk.internal.vm.annotation.NullRestricted, @jdk.internal.value.ValueClass.newNullRestrictedNonAtomicArray. Also, there is a reason value classes are allowed to be null. This is because nullness types will be a key factor to the java language.

New comment by joe_mwangi in "Java 27"

joe_mwangi — Tue, 15 Sep 2026 19:40:28 +0000

Once it gets nullness types, hackernews is gonna explode!

New comment by joe_mwangi in "Java 27"

joe_mwangi — Tue, 15 Sep 2026 19:33:06 +0000

Typeclasses caught me by surprise. Smart move by the java team.

New comment by joe_mwangi in "JDK 28 EA Build 10 Now Available with JEP 401: Value Objects (Preview)"

joe_mwangi — Thu, 13 Aug 2026 07:03:18 +0000

Also, future specialisation if it is introduced, it will enable the JIT to get enough information to ensure becomes stored in cpu registeres or enable to be flattened in memory.

New comment by joe_mwangi in "JEP 401: Value Objects (Preview) merged to OpenJDK master"

joe_mwangi — Fri, 31 Jul 2026 12:17:41 +0000

Yeaaah. They are going to introduce approaches for the programmer to decide if tearability is allowed or not. Already there are internal annotations for fields and types to enable it that probably will become a language feature in future.

New comment by joe_mwangi in "JEP 401: Value Objects (Preview) merged to OpenJDK master"

joe_mwangi — Fri, 31 Jul 2026 11:08:59 +0000

They are researching to have immutable arrays. Also multifields (stack allocated arrays as fields in value classes). So, there is a possibility.

New comment by joe_mwangi in "Why low-latency Java still requires discipline?"

joe_mwangi — Mon, 06 Jul 2026 16:40:34 +0000

I've done some tests with current value classes in latest prototype with full optimisation through annotation. Apparently, everything was being compiled to assembly code with no gc calls. It seems this old school ideology of slow java is about to end in near future. I'm actually intrigued how it will compete with Rust which can't optimise code further while running, while JVM JIT has more info which it could aggressively further optimise, especially hot paths.

New comment by joe_mwangi in "JEP 539: Strict Field Initialization in the JVM moved to preview"

joe_mwangi — Thu, 02 Jul 2026 21:01:57 +0000

Also, this will be used for future null-restricted types.

New comment by joe_mwangi in "Project Valhalla, Explained: How a Decade of Work Arrives in JDK 28"

joe_mwangi — Fri, 26 Jun 2026 09:07:39 +0000

Better late than never.

New comment by joe_mwangi in "Project Valhalla, Explained: How a Decade of Work Arrives in JDK 28"

joe_mwangi — Sat, 20 Jun 2026 08:50:11 +0000

This time, 30mb.

New comment by joe_mwangi in "Project Valhalla, Explained: How a Decade of Work Arrives in JDK 28"

joe_mwangi — Sat, 20 Jun 2026 08:49:23 +0000

Yup. By design, value classes will use cpu registers as a 1st priority instead.

New comment by joe_mwangi in "Project Valhalla, Explained: How a Decade of Work Arrives in JDK 28"

joe_mwangi — Fri, 19 Jun 2026 21:06:54 +0000

Until they implement member patterns. https://openjdk.org/projects/amber/design-notes/patterns/tow...

New comment by joe_mwangi in "Project Valhalla, Explained: How a Decade of Work Arrives in JDK 28"

joe_mwangi — Fri, 19 Jun 2026 21:05:08 +0000

> yet But up the comment section, someone thinks they won't be there 'in the future'

New comment by joe_mwangi in "Project Valhalla, Explained: How a Decade of Work Arrives in JDK 28"

joe_mwangi — Fri, 19 Jun 2026 16:47:57 +0000

And I notice, people aren't aware more things are being planned for. For example, the carrier classes being proposed, they will separate state description with state representation and this is where value classes will shine syntactically.

New comment by joe_mwangi in "Project Valhalla, Explained: How a Decade of Work Arrives in JDK 28"

joe_mwangi — Fri, 19 Jun 2026 16:22:50 +0000

And the only syntax change is adding 'value'.

New comment by joe_mwangi in "Project Valhalla, Explained: How a Decade of Work Arrives in JDK 28"

joe_mwangi — Fri, 19 Jun 2026 16:10:06 +0000

Since they plan to have null-restricted types, then I don't see any issue.

New comment by joe_mwangi in "Project Valhalla, Explained: How a Decade of Work Arrives in JDK 28"

joe_mwangi — Fri, 19 Jun 2026 16:08:41 +0000

But with null-restricted types, Integer! and int has no difference semantically and representation. They plan to introduce null-restricted types in future.

New comment by joe_mwangi in "First Valhalla related stuff will land in Java 28"

joe_mwangi — Wed, 10 Jun 2026 18:50:35 +0000

This is awesome. First step to an interesting direction of the language.