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Java 21 makes me like Java again

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Re: Java 21 makes me like Java again

#121

Post by mongol »

riku_iki wrote: post #88
gabereiser wrote: post #82

Earlier quoted context omitted.

Golang or Rust. If it’s a web service or microservice: Golang hands down. If it’s a desktop software or game engine, rust. If you just want to typescript your way to success, deno and vite. If you’re too introverted for Rust, Zig. Java, whether it be spring, micronauts, jee, whatever, is wasting CPU and Memory in the cloud costing you and/or your enterprise money.

> Golang golang is probably a good contender for business logic code where Java is widely used, but I feel ecosystem (libs, integrations) is not comparable to Java, so you take some risks while choosing golang.

I have not used Go generics, but it's viability as a business logic language would depend on that.

Re: Java 21 makes me like Java again

#122

Post by c048 »

gabereiser wrote: post #111
lukev wrote: post #73

Earlier quoted context omitted.

Having worked extensively in Java, Node, and Python, I’ll take the JVM ecosystem absolutely any day of the week. Me and my catheter will be over here delivering actual software while you figure out how React 32 broke your transcompiler.

Except I’m over here serving 10x the traffic with 10x less cloud spend on CPU and Memory for hosts.

Maybe you should upgrade from Java 1.4...

Re: Java 21 makes me like Java again

#123

Post by kaba0 »

insanitybit wrote: post #49
wslh wrote: post #40

Earlier quoted context omitted.

Please ELI5 what is wrong with inheritance and/or how Java have it wrong. Do we need to go back to a new object oriented undegraduate course? Genuinely asking.

Inheritance provides "is a" relationships between classes. At a time when people would spend months designing their software upfront, building big diagrams of classes, etc, this was not so bad. You'd have a very clean system design that maps directly to your class design. The problem is when things change. A simple example - you build a classification of all life and it is built upon the idea that everything "is a" p…

> you build a classification of all life and it is built upon the idea that everything "is a" plant or animal

With all due respect, this and similar examples are just plain wrong, and I really can't take anyone seriously when that example is used. The point of programming, and its abstractions is to help you complete a task, and make the implementation maintainable and easy to reason about. I think grabbing the "is a" part is fundamentally bad -- there is no point in creating a taxonomy in and of itself, this is no database for that data. Inheritance sometimes is the correct abstraction and while it is definitely overused, when it's correctly applied there isn't really another abstraction that would fit better. E.g. see a graphics library's Node class as the stereotypical correct application.

Re: Java 21 makes me like Java again

#124

Post by richardw »

Supermancho wrote: post #77
insanitybit wrote: post #30

Earlier quoted context omitted.

> I rarely see inheritance used in practice in java code bases. That seems absurd to me and I have a hard time understanding it, honestly.

> I rarely see inheritance used in practice in java code bases. Without some specific call-out, it can be assumed that this is a very niche viewpoint that has no bearing on modern development. The vast majority of projects use inheritance, today. Does it use Spring? extends SpringBootServletInitializer Meaningful responses using values from a request? extends OncePerRequestFilter Formatting exception handling respons…

You need to inherit to create anything that is a class. But the focus is on composition. You inherit from useful classes so you can build the solution using composition.

I don’t like modern Java because there’s too much non-Java magic code. Layers of stuff that “helps” but removes me from the language. Entire programs written in config and special text wrapping classes and methods. How it works requires understanding multiple intersecting languages that happen to be strung together in .java files.

Edit: when something is in config it’s not checked at compilation. Every environment from dev to prod can have its own config so when you compile in dev you don’t know what’ll happen in prod. I know: let’s add more tools and layers.

Re: Java 21 makes me like Java again

#125

Post by erik_seaberg »

insanitybit wrote: post #79
northern-lights wrote: post #31

The biggest feature in Java 21 is the release of Virtual Threads: https://openjdk.org/jeps/444 For some reason, this is missing from the article. If there was any feature that would sway existing Golang developers to switch to Java, it would be this. It would perhaps also convince the haters of the reactive-style concurrency patterns.

`Executor.newVirtualThreadPerTaskExecutor` versus `go` really gets to the heart of why I think that Go developers aren't going to be switching. edit: Sorry, it's actually: try (var executor = Executors.newVirtualThreadPerTaskExecutor()) { executor.submit(...) ) instead of `go`

You’re likely to need a lot of boilerplate that “go” statement won’t generate: pass and wait for completed results, report errors, timeouts, cancellation, bounded parallelism, pushback, service monitoring.

Re: Java 21 makes me like Java again

#126

Post by insanitybit »

erik_seaberg wrote: post #125
insanitybit wrote: post #79

Earlier quoted context omitted.

`Executor.newVirtualThreadPerTaskExecutor` versus `go` really gets to the heart of why I think that Go developers aren't going to be switching. edit: Sorry, it's actually: try (var executor = Executors.newVirtualThreadPerTaskExecutor()) { executor.submit(...) ) instead of `go`

You’re likely to need a lot of boilerplate that “go” statement won’t generate: pass and wait for completed results, report errors, timeouts, cancellation, bounded parallelism, pushback, service monitoring.

My comment is perhaps too glib. I'm not trying to say that Go is better, I frankly like Java more. I only mean that if I'm in a Go mindset and I read the linked document on virtual threads, and I see that code example, I'm going to close the tab.

Re: Java 21 makes me like Java again

#128

Post by wayfinder »

logicchains wrote: post #83
wayfinder wrote: post #75

Earlier quoted context omitted.

If you type everything with interfaces in your codebase, you are much less tied to inheritance. In fact, everyone could be written to be composed. However Java doesn’t support type union so you can get into some ugly and verbose situations but the JVM doesn’t really check type so this is more a compile-time issue and could be fixed in a future Java language revision.

>However Java doesn’t support type union so you can get into some ugly and verbose situations Isn't the "sealed interface" described in the OP blog post a type union? Or you mean anonymous unions?

Definitely referring to anonymous unions too. Without them, there’s still friction sometimes which makes union types unnatural.

I haven’t written Java in a while and I can’t remember if you could sometimes fake a type union using a generic type on a method, but if you can, it’s definitely super ugly and would raise eyebrows during any code review.

Re: Java 21 makes me like Java again

#129

Post by loxias »

OJFord wrote: post #65
loxias wrote: post #48

Earlier quoted context omitted.

> I agree C++ is bloated in a 'just make it a setting' / 'add this feature' / 'kitchen sink' sort of way. Interesting. Can you expand on this, explain more? I honestly don't know what you mean or are referring to -- and I'm a heavy modern c++ advocate -- but suspect if I did it might expand my mindset/viewpoint a bit. :)

Honestly I haven't actually used it since C++14 was new, but it's a common complaint IME that each 'edition' (as Rust would call it, I don't know remember the term, standard?) adds too much, there's too many ways of doing things, variations of pointers, boost, and so on. I think a lot of people wish it had stayed at say C++7, a mature C superset, but that's enough now. I probably should have said 'I understand' rathe…

Ohhh, I get what you mean now, thank you! I understand (and mildly disagree). :)

Yeah, C++ is a living language, I can respectfully see that bothering some people. I viewed c++98->c++11 as essentially a new language with c++14 and c++17 being "bug fixes" for the "new language" that is c++11. But certainly, it can require more learning about every decade now.

Re: Java 21 makes me like Java again

#130

Post by kaba0 »

wayfinder wrote: post #87
insanitybit wrote: post #49

Earlier quoted context omitted.

Inheritance provides "is a" relationships between classes. At a time when people would spend months designing their software upfront, building big diagrams of classes, etc, this was not so bad. You'd have a very clean system design that maps directly to your class design. The problem is when things change. A simple example - you build a classification of all life and it is built upon the idea that everything "is a" p…

This problem is partly a type system limitation however. In a more flexible type system with union types and other magical features, your example problem would be less of an issue. However Java has an extremely limited type system so there is no middle ground between composition and inheritance. Once you choose one way, there is no “middle step” to migrate over.

Union types are very rare (scala, typescript are the notable ones I can think of that implement it), most other languages only have sum types (which includes java as well, see sealed interface/classes), where you have to create each unique set of types you want to use separately, wrapping each option into a marker type basically.
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