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All New Java Language Features Since Java 21

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Re: All New Java Language Features Since Java 21

#41

Post by jghn »

watwut wrote: post #35
vips7L wrote: post #12

Earlier quoted context omitted.

The new features make the code easier to read. For example var: List accounts = List.of(new Account(1), new Account(2)); var accounts = List.of(new Account(1), new Account(2)); It just reduces visual noise and boilerplate that you already know. Java 8 is also a slow and old runtime. It performs terribly in 2025. Here’s a quote from 2020 and the gap has only gotten wider [0]: > JDK 8 is an antiquated runtime. The defa…

There is about zero difference in readability of your two statements, rending var not useful. And 'var accounts = calculateAccounts(something)' is literally less readable, because now you dont see what exactly accounts is. Var statement speed up writing, then are either irrelevant or gets rewritten to types for better readability.

> is literally less readable

Please point me to an objective measure of "readability" that holds for all people. And then demonstrate that your example is "literally" lower on that scale.

Re: All New Java Language Features Since Java 21

#42

Post by deknos »

nunobrito wrote: post #7
tombert wrote: post #4

I am a big functional programming geek. I am one of the few people on the planet who can honestly say I have been paid to write F#, Haskell, Clojure, and Erlang. I have spoken at FP conferences like six or seven times, and I have shit on Java for most of my career. And yet, my latest talk at Lambda Days basically boiled down to “Java 21 and later don’t actually suck anymore”, and I genuinely do mean that. Java 21 is…

Programming language is a tool. Java developers value stability and ease of understanding for the code. I've seen the nice features you complain that don't get used, reality is that nobody wants to waste time knowing them unless they are intuitive to use. Especially when are forcing to use newer JDKs. There is no value in solving a challenge in a way that only you understand or make others lose time trying to underst…

You know what's quite more important?

* Performant and safe standard library. * batteries included * a good way to actually care about managing dependencies, during build and runtime.

Okay, you got your stuff, please everyone now let's care about the standard library and that it really good.

Re: All New Java Language Features Since Java 21

#43

Post by jfengel »

pico303 wrote: post #27
vbezhenar wrote: post #20

Earlier quoted context omitted.

You should write Map items = new HashMap (); It allows you to limit `items` usage to `Map` supertype and allows you to swap implementation easily, if necessary. `var` is weird feature, because it allows people to use implementation-specific methods methods and tie code to a single implementation, essentially making it less agile. There are valid use-cases for `var`, but IMO this feature should not have been added to…

No, you shouldn't write that. Your variable should represent the complete implementation. Where you use it should be as generic as possible, for example, the parameter in a function call.

Why would you want that? The whole point of an interface or superclass is to let you swap implementations without changing everything.

I also like the nudge it gives you to use only the higher level methods, rather than the ones specific to the subclass unless they're needed. That also improves flexibility.

Re: All New Java Language Features Since Java 21

#44

Post by pyrale »

nunobrito wrote: post #7
tombert wrote: post #4

I am a big functional programming geek. I am one of the few people on the planet who can honestly say I have been paid to write F#, Haskell, Clojure, and Erlang. I have spoken at FP conferences like six or seven times, and I have shit on Java for most of my career. And yet, my latest talk at Lambda Days basically boiled down to “Java 21 and later don’t actually suck anymore”, and I genuinely do mean that. Java 21 is…

Programming language is a tool. Java developers value stability and ease of understanding for the code. I've seen the nice features you complain that don't get used, reality is that nobody wants to waste time knowing them unless they are intuitive to use. Especially when are forcing to use newer JDKs. There is no value in solving a challenge in a way that only you understand or make others lose time trying to underst…

> Especially when are forcing to use newer JDKs.

Dude, java 8's eol was 8 6 years ago, now. I have nothing gainst waiting a bit for "newer JDKs", but way too often the pattern is that teams use the oldest possible JDK and only migrate several months/years after the last possible vendor has sunset their support.

> Java 8 was the peak of development age for the JDK.

To me it looks it was merely the point where your stopped caring.

Re: All New Java Language Features Since Java 21

#45

Post by LelouBil »

brap wrote: post #30

After trying out many languages at many places, I reached the conclusion that Java, as weird as it may be, is my favorite language. There were times I hated it, but turns out I really just hated messy, over-engineered legacy code and working in a gray cubicle at aging MegaCorps. The language itself is quite beautiful when used properly and with modern features. It just really needs a makeover and better tools.

Did you try Kotlin ?

Re: All New Java Language Features Since Java 21

#46

Post by pyrale »

jghn wrote: post #41
watwut wrote: post #35

Earlier quoted context omitted.

There is about zero difference in readability of your two statements, rending var not useful. And 'var accounts = calculateAccounts(something)' is literally less readable, because now you dont see what exactly accounts is. Var statement speed up writing, then are either irrelevant or gets rewritten to types for better readability.

> is literally less readable Please point me to an objective measure of "readability" that holds for all people. And then demonstrate that your example is "literally" lower on that scale.

Readability was a term coined by people writing languages that are litterally unusable without an IDE to hide stuff when they render the source file to explain why refusing to learn languages with curly braces is sane.

Re: All New Java Language Features Since Java 21

#48

Post by tombert »

santiagobasulto wrote: post #32
tombert wrote: post #4

I am a big functional programming geek. I am one of the few people on the planet who can honestly say I have been paid to write F#, Haskell, Clojure, and Erlang. I have spoken at FP conferences like six or seven times, and I have shit on Java for most of my career. And yet, my latest talk at Lambda Days basically boiled down to “Java 21 and later don’t actually suck anymore”, and I genuinely do mean that. Java 21 is…

This is amazing news! Two questions for you: - how’s the environment? Build tools, dependency management, etc. it used to be a PitA back then. - how has the typing system and generics evolved to support this? Have they introduced any type of variance?

Generics still kind of suck but they’re workable enough. As far as I am aware they’re broadly unchanged and I don’t think they added any kind of new variance.

It turns out, though, it’s still good enough for sealed interfaces and the like; I don’t have too many issues with it, though that might just be Stockholm syndrome at this point.

Maven is terrible as always but Gradle is generally fine. I use IntelliJ community edition solely for Java and it works well enough for what I need.

It’s not like Java is going to replace F# for me or anything, but I do genuinely think it’s more fun to write now than it used to be.

Re: All New Java Language Features Since Java 21

#49

Post by jauntywundrkind »

watwut wrote: post #35
vips7L wrote: post #12

Earlier quoted context omitted.

The new features make the code easier to read. For example var: List accounts = List.of(new Account(1), new Account(2)); var accounts = List.of(new Account(1), new Account(2)); It just reduces visual noise and boilerplate that you already know. Java 8 is also a slow and old runtime. It performs terribly in 2025. Here’s a quote from 2020 and the gap has only gotten wider [0]: > JDK 8 is an antiquated runtime. The defa…

There is about zero difference in readability of your two statements, rending var not useful. And 'var accounts = calculateAccounts(something)' is literally less readable, because now you dont see what exactly accounts is. Var statement speed up writing, then are either irrelevant or gets rewritten to types for better readability.

I tend to agree here, I prefer explicitness. Even though yes it does mean some pain when refactoring, it also creates very clear diffs showing impact, which I consider a positive.

Ideally this could all be dealt with via tools. An IDE that shows whatever the user prefers, but is actually saving into a format defined for the repo.

Re: All New Java Language Features Since Java 21

#50

Post by p2detar »

ivanjermakov wrote: post #24
bullen wrote: post #18

The only new feature I might use since 1.8 (that only had NIO stability and GC improvements over 1.7) are the virtual threads without pinning in 24.

We extensively use vars, switch expressions, collector methods, String format methods, records, instanceof narrowing. Just from the top of my head.

Same here, plus sealed classes - a very powerful feature.

What I actually haven’t used up to this point are VTs. I got a service that implements a job queue and it currently works flawlessly with scheduled executor pool. I’m reluctant to go with VTs before evaluating what implications that may have.

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