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Java 21 makes me like Java again

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Re: Java 21 makes me like Java again

#451

Post by za3faran »

bedobi wrote: post #200
ivan_gammel wrote: post #158

Earlier quoted context omitted.

As someone writing code on Java since v1.0 and making tech strategy decisions on the C-level, I consider myself sane and experienced enough to say that Java is something that will do the job well and can be the primary choice for startups and new projects. Kotlin as a platform is not mature enough to deserve the same qualification.

I'm sure you have done great work in Java, as have many of us, and for many of those years, Java really was the best tool for many jobs. But that was then, now is now. I'm not saying Java doesn't work, even for greenfield projects today. It works fine. But me and many others also think it's not enough for something to merely work, especially not when there are other much better and more modern tools. (which Java is d…

> I've worked with the kind of engineers who are still doing Java + Spring like it's still the 90s, and they're not the ones you want on your projects

And I've worked with programmers who use the latest fad of the day (golang, etc) and they're not the ones you want to have on your projects.

> The best talent don't even want to consider working with Java if they can help it.

Not in my experience.

Re: Java 21 makes me like Java again

#452

Post by za3faran »

jhaenchen wrote: post #164
bb88 wrote: post #99

Earlier quoted context omitted.

I've never been a big fan of dependency injection. It solves a problem with unit testing in Java, sure, but the reality is that Java could have done some nifty things to help alleviate that as well.

Agreed. Java injection frameworks are opaque and accomplish what they need to with overly powerful mechanisms because of the nature of the language. You don't see that sort of nonsense in python.

Nothing to do with the nature of the language, but with the nature of the program.

If you're writing a few line script, you don't need a DI container. Once your program gets large, it becomes extremely messy without one. It's no surprise projects like [1] exist.

[1] https://github.com/ets-labs/python-dependency-injector

Re: Java 21 makes me like Java again

#453

Post by za3faran »

mrkeen wrote: post #419
kaba0 wrote: post #105

Earlier quoted context omitted.

Prefer composition over inheritance has been a common mantra for at least a decade, if not more. Maybe you should undergo the last decade of development and training. There will always be shitty devs, and since java is one of the biggest languages, it definitely has more than some ultra niche academic language no one uses. I don't think it is the fault of the language though, or if that somehow were a reason to choos…

> Prefer composition over inheritance has been a common mantra for at least a decade, if not more. Maybe you should undergo the last decade of development and training. What are some other well known mantras? The null reference is a billion dollar mistake? Minimise mutability? Maybe the language designers and library writers could catch up too.

Records and value/primitive classes are immutable, not to mention https://openjdk.org/jeps/401

Re: Java 21 makes me like Java again

#454

Post by olavgg »

kaba0 wrote: post #397
neonsunset wrote: post #224

Sad this gets to front page while a blog post which documents that .NET 8 has 200 A4 pages worth of performance improvements gets absolutely ignored. C# keeps being the language people are looking for but don't know about.

Since it is a Java thread, I’m gonna mention that ecosystem-wise, the JVM is just much much bigger and of higher quality - you very often see copied JVM packages in C# with much less features, less stability, and often even being paid. With that said, it is a cool language and platform, that is indeed underhyped.

This 100x, C# and Java are also very similar programming languages. C# may be a better language, but the difference is minimal. Most C# developers claiming that C# is a better language often don't know Java. I remember one C# guy telling me that Java didn't have closures before Java 8, which was not quite true. Java developers had access to Groovy which had closures. Groovy may be another programming language, but it has always had 99% Java syntax compatibility and they both compile to the same byte code and work seamlessy together. Groovy 4 also has LINQ if you like that. And using Groovy is no harder than including it as a dependency in Gradle/Maven.

Java eco system is so vast, and of top notch quality, with excellent documentation available for free. It enables businesses to move faster, at a pace most other languages cannot offer. It's not perfect, especially I find data sciene libraries lacking in Java compared to what the Python eco system offers. But depending on the task I try to choose the right tool for the job, not the same language for every job.

Re: Java 21 makes me like Java again

#455

Post by nine_k »

adrianmsmith wrote: post #430

The "Sealed classes" feature, as described here, just feels all wrong to me. They are saying that if you have a (normal) interface, anyone can create a new class implementing it. So if you do if (x instanceof Foo) { ... } else if (x instanceof Bar) { ... } ... then your code will break at runtime if someone adds a new class, as that code won't expect it. So the article is saying the solution is to use the new "sealed…

There are valid use cases for that.

Consider a security interface of some sort, e.g. such that validates a security token.

With a normal interface, it is easy to implement it and ignore the token (allow all), siphon off the token, add a backdoor, etc. If a class doing that is somehow injected where a security check is done, it can compromise security.

Now with a sealed interface, there cannot be new, unanointed implementations. If you get an object that claims to implement that interface, it's guaranteed to be one if the a real, vetted implementation that does the actual security check, not anything else. You've just got rid from a whole class of security bugs and exploits.

Re: Java 21 makes me like Java again

#456

Post by pkolaczk »

adrianmsmith wrote: post #430

The "Sealed classes" feature, as described here, just feels all wrong to me. They are saying that if you have a (normal) interface, anyone can create a new class implementing it. So if you do if (x instanceof Foo) { ... } else if (x instanceof Bar) { ... } ... then your code will break at runtime if someone adds a new class, as that code won't expect it. So the article is saying the solution is to use the new "sealed…

The solution with sealed classes also allows anyone to extend the code, but in a different dimension than the solution with an interface method.

The solution with interface method and virtual call is very inflexible when you want to add new operations instead of adding new classes. If you want to just add one new operation, then you have to go to all the implementations and add new methods. And you possibly break the implementations you don't have access to. And all those methods must be defined in a single class, even if they are unrelated to each other. This seriously degrades code readability (and performance as well - those vcalls are not free either).

The sealed class extends much better in this case. You just add a new switch in one place and done. No breaking of backwards compatibility.

This is the famous expression problem.

https://pkolaczk.github.io/in-defense-of-switch/

Re: Java 21 makes me like Java again

#457

Post by nine_k »

impulser_ wrote: post #187
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.

I don't think any existing Go developer is going back to Java. I worked with Java for 10 years and switched to Go and I will never go back. This is mostly because applications and libraries are so hard to reason about and understand due to inheritance, packaging, OOP, build tools ect compared to Go. Go is simple. It's easy to understand, read, and maintain. The packaging is like how you would package files on your co…

Go has made many decisions that i'm not happy about.

If they did one thing exactly right on the language level, it's the [lack of] OOP: interfaces in their implementations, and no inheritance, overridden methods, covariance / contravariance games, etc.

You can of course write in Java in that style: only extend interfaces, never inherit classes. But many libraries, including the standard library, actively refuse to cooperate.

Re: Java 21 makes me like Java again

#458

Post by kamma4434 »

neonsunset wrote: post #226
arein3 wrote: post #197

Earlier quoted context omitted.

Exception handling and generics are missing key pieces from go. But adding them will make go look like java. I just wish java would add null safety in the type system in a first citizen way. For enterprise use java has no competitors. You have c# which is microsoft trying to estabilish nash equilibrium fu*ing the developers. I am a bit worried about ever increasing complexity and a steep learning curve, but seems lik…

Java is an inferior language to C#. To get a superior language you would likely have to go for Kotlin. There is no comparison, because Java gets features today that C# had for years. Not even mentioning having to retrofit green threads because adopting async/await (used by TS, Rust, Swift and other languages) is impossible at this point.

Async/await is an inferior product compared to threads, for so many reasons (function coloring and meaningful stack traces come to my mind). Keeping the same interface as native thread, plus structured concurrency, are best of breed.

Many uncancellable threads + mutability + goroutine panic kill it all are serious issues for golang.

Re: Java 21 makes me like Java again

#459

Post by za3faran »

gabereiser wrote: post #188
DandyDev wrote: post #172

Earlier quoted context omitted.

Do you feel good about yourself, talking down on people that made a perfectly valid choice by developing software in Java? Let's look at the alternatives you mentioned: Rust and Golang. Java compared to Golang is a much more expressive language. Java compared to Rust is a much easier language because you have a garbage collector for the majority of the cases you don't need the manual memory controls that Rust offers…

Google invented Go. Netflix uses Java and Rust and Go. Twitter used to use Scala. GitHub uses Ruby on Rails. EpicGames uses C++. Instagram uses Python. Everybody uses something. Now, if you have building on top of your organizations previous 10 years of engineering, you’re probably going to be writing Java and it’s probably going to be complicated. I’ve been there. I wrote Java for 15 years. I won’t anymore. I’m in l…

> Google invented Go.

A handful of people at google invented golang is the more correct thing to say.

Yet, google continues to use Java at a much much bigger scale than golang.

golang is simplistic, not simple. Once you work on large golang code bases you'll see the challenges and messes it causes.

Re: Java 21 makes me like Java again

#460

Post by pkolaczk »

pjmlp wrote: post #423
ashishb wrote: post #275

Earlier quoted context omitted.

Fully compiled languages have another huge advantage. If you write a tool in Python and targeted say Python 3.10 then people using Phython 3.9 might not be able to use it. So, you really can't use latest and greatest features of Python 3.11 or 3.12. However, with Go, you can build your tool in Go 1.21 or whatever, and the user does not even need a Go toolchain on their machine. I was planning to write a small side-pr…

Unless dynamic linking is used, or OS APIs change between version, or specific OS files change location.

Go binaries are traditionally statically compiled.
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