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Comment by jwr | Hacker News Reader

As a Clojure programmer, I'm so happy that I'm getting all these improvements over many years. It's fashionable to complain about Java — but I don't use Java, and yet I benefit from all the fantastic work that is being done on the JVM.

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The excellent backwards compatibility rocks too. This weekend I wanted a library to diagram the class hierarchy of a Java project I put together.

I found a 10 year old library that worked with no issues, I was done in minutes even though I rarely use Java or Clojure so my familiarity is low. There are very few languages where I would have a similar experience.

https://github.com/stuartsierra/class-diagram

I had a similar experience with some random jar visualizing some algorithm which I downloaded from a professor’s website, which just worked.

That is the positive attitude, it always irks me when guest language comunities bash the platform that make their language even possible in first place.

Everything sucks, but then they gladly take the platform, the ecosystem of libraries, debuggers and what not from the host platform.

It depends, some languages have more to complain about than others. I’d argue F# on .net basically had to spend years treading water while Microsoft’s various teams figured out .net core/framework. The community feels like it lost a lot of inertia it used to have.

I feel that the latest JVM developments have really been aimed at the developers: easier syntax, nice threading support, fast garbage collector, etc. On the GUI side I know that JavaFX has also been pushing for more features and more performance to become competitive again.

Is it still fashionable to bash Java? I remember the bashing of Java around 15 years or so ago, IMO justifiably because it could be slow to the point of making programs unpleasant to run.

But nowadays… I mean Java can be a bit verbose, but other than that it seems like a fine language and the JVM is pretty great. Plus we don’t have annoying Java applets in our browsers anymore (perhaps one of the main sources of legitimate Java hatred, and something so bad that we’ve intentionally all forgotten about it).

Now I'm going to go look and see where Jython's parity is to Python.

EDIT: Only supports 2.7(x); that makes me sad.

Graal Python is compatible with python 3.x https://www.graalvm.org/python/

> Is it still fashionable to bash Java?

People do it more now rather than less.

Nowadays people run on hype and need a scapegoat.

I say this all the time to people that say they want to use Node because they hate Java. There are so many languages that you can execute on the JVM. It’s almost unfortunate that it’s still called the JVM. It think the JVM needs a re-branding. Even if they just change the meaning of the J. I suppose that is what GraalVM is doing, but it’s an awful name and its purpose isn’t being conveyed well. The JDK should just switch to this VM and get rid of the name JVM.

These are just my opinions.

I haven't been in that world since Java 7. What's the startup time on the JVM these days? It used to be a pretty hefty cost, and it didn't seem like it would get much better because of the way class loading was done.

Not sure what startup time matters for running a persistent service is, and it's obviously tied to hardware. You can get applications up and running in less than second or so (we were using Micronaut to resolve dependencies at compile time). If you use GraalVM you can compile to native code and now we're talking a few tens of milliseconds to get an application up and running (or execute and exit).

That was always the story back then, too — the assumption that no one writes anything other than services with long uptimes. No CLI tools, no lambdas, no quick-launching GUIs. Sounds like that bias hasn't really changed over the years?

Not sure if it's a "bias". The JVM does start up slowly. This has never been an issue for me in all the years I've been using Clojure.

If I need "scripts" with short start-up times, I'll use Babashka (GraalVM) or ClojureScript (Node). Same language, instant start-up. But then I don't expect to get good performance from those VMs for long-running services with large memory allocations.

Use the right tool for the job at hand?

You pay for what you use. If you bring in a litany of libraries to connect to some endpoint in every conceivable IPC mechanism then sure, it will take some time (but let’s not forget that it would also take considerable time with native machine code). But besides very very frequently run CLI tools like ls, the problem is entirely overblown. Come on, quick-launching GUIs? I hardly even remember that being a thing.

You pay for what you use.

Exciting, if true. So, for example, could I choose to not use garbage collection or class loading or JIT compilation and avoid paying their costs?

I was quite obviously talking about loading many classes.

But.. yeah, you can disable the GC and also the JIT compiler, for whatever reason.

JVM still has some limitations. https://stackoverflow.com/a/2682962/31667 Those actually influence either the design or the performance of the higher level language.

That post is 13 years old.

Yes it is - that doesn't make it wrong. The type erasure is still a JVM limitation.

The same way is it for Haskell?

The answer is 6 years old if we count the last modification time.

And the last modification was only wording, with the same 13 years old content. [0] Always check what changed in SO posts, because this practice is very common.

[0] https://stackoverflow.com/posts/2682962/revisions

TIL, thank you!

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