[tombert]

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 actually fun to write, even for a grumpy FP advocate like me. Virtual threads make concurrency a lot simpler, and now that there’s proper records and ADTs (in the form of sealed interfaces), along with pattern matching, the language is actually pleasant to use. I haven’t dived into 25 yet, but I suspect I will like it as much or more than 21.

The biggest issue, though, is that Java programmers won’t use the new features. It was like pulling teeth at my last job to get people to use stuff from Java 8 (e.g. the `var` keyword), and none of my coworkers even knew how to use NIO or BlockingQueues which I think predate agriculture. I mean, hell, I had explain what “fairness” was to engineers when using a ReentrantLock because someone “corrected” my code with `synchronized`.

I don’t think Java makes people into bad programmers, but I do think it selection-biases for intellectually unambitious engineers. They learn exactly enough Java in college to pass their courses, and then get a job at a BigCo that doesn’t strictly require ever learning anything more than what they were taught in their “intro to data structures” course.

I have met some extremely intelligent Java engineers who do have intellectual curiosity, so I am not saying it affects everyone, but I do think that they are the minority. Java 25 might add every feature to make my wildest dream come true but it won’t matter if I am not allowed to use it.

[michaelrpeskin]

> I don’t think Java makes people into bad programmers, but I do think it selection-biases for intellectually unambitious engineers. They learn exactly enough Java in college to pass their courses, and then get a job at a BigCo that doesn’t strictly require ever learning anything more than what they were taught in their “intro to data structures” course.

I think that's a fair comment, but also there's this perspective: I first touched Java 1.1 in 1997 in college, and only for a semester. Then for the next 22 years never looked at a line of Java, working mostly in C++ and Python plus dabbling in FORTRAN for high performance stuff that needed to be written there. I generally consider my self not intellectually unambitious.

Then I moved to a Java shop who specifically needed high performance math (well at least as high performance as you can get in Java, which is actually pretty good now). But we stick to Java 8 compatibility because we have some BIG customers who require that because of LTS on Java 8. There are some nice constructs that would help make the code more readable and modern, but when you need to support people and actually make money you do what you need to.

[tombert]

Sure, I am not claiming that you have to use every new feature every day 100% of the time. Obviously there are cases where you can’t upgrade for legal or compliance or “customer is just being difficult” reasons.

A lot of Java jobs aren’t that though, especially internal applications. A lot of places are running Java 17 or Java 21 on all their servers, literally have no plans to ever support anything lower, but the engineers are still writing Java like it’s 2003. That is what’s maddening to me.

[javanonymous]

I think it has a lot to do with work culture. Many tend to mimic what others are doing in order to not stick out.

At my previous job some were able to change that by consistently using "modern" features of Java. It inspired others to change and eventually we ended up with a good code base.

Be the one to start the change by implementing new features using good code. This will give others "permission" to do the same. Also try to give soft suggestions in code reviews or pair programming of simpler ways to do it (don't push too hard)

At my current job all of us were eager to try the latest features from the start, so we never had to convince new hires.

[tombert]

That's how it kind of was in my last job [1].

I know I came off as a bit negative, but in fairness to them, they did more or less continue working on what I was doing using the newer Java 21 features, and after I got a few pretty interesting changes merged in some of the more junior engineers started using them too; particularly I was able to successfully evangelize against the use of `synchronized` in most cases [2] and got at least some people using queues to synchronize between threads.

It honestly has gotten a fair bit easier for me since I've been doing this for awhile; at my last job I was the most experienced person on my direct team (including my manager) and one of the more experienced software people at the company, so I was able to throw my weight around a bit more and do stuff how I wanted. I tried not to be a complete jerk about it; there were plenty of times people would push back on what I was doing and I would think about it and agree that they were probably right, but I outwardly rejected arguments that seemed to be based on "I didn't learn this in university so it's wrong".

I have had other jobs (at much bigger companies) where they were not amenable to this. I would try and use new features and my PRs would be rejected as a result, usually with some vague wording of "this way is faster", which I later found out was (as far as I can tell) always a lie.

[1] It is not hard to find my job history but I politely ask you do not post it here.

[2] I'm sure someone here can give me a contrived example of where `synchronized` makes sense but if you need mutexes I think you're almost always better off with a ReadWriteLock or ReentrantLock.

[nunobrito]

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 understand the logic.

Java 8 was the peak of development age for the JDK. Everything that came after isn't really memorable nor helpful, especially lambdas. You mention "var", why would we ever want in Java to hold a variable that you can't read immediately what is the type? That is a source of bugs and time waste to track down what object is being used.

I don't mind you are happy with all these changes, just remember that we absolutely don't care about them nor will make much of an effort because in the end of the day we don't want to follow the same route of other programming languages unable to handle gigantic and complex platform systems.

This isn't a competition to showoff who can apply new tricks, we absolutely don't care about functional programming. Java code must be simple and easy for anyone to read, that's it.

[vips7L]

The new features make the code easier to read. For example var:

    List<Account> 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 default Parallel collector enters huge Full GC pauses and the G1, although having less frequent Full GCs, is stuck in an old version that uses just one thread to perform it, resulting in even longer pauses. Even on a moderate heap of 12 GB, the pauses were exceeding 20 seconds for Parallel and a full minute for G1. The ConcurrentMarkSweep collector is strictly worse than G1 in all scenarios, and its failure mode are multi-minute Full GC pauses.

You’re doing a disservice to everyone by continuing to use and glorify it.

[0] https://hazelcast.com/blog/performance-of-modern-java-on-dat...

[Twirrim]

Using Java 8 doesn't mean using the java 8 JDK. It just means not using the newer features. I don't see anything in the parents post about restricting which JDK they use.

[vips7L]

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

Still glorifying it.

[watwut]

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.

[leetcrew]

the advantage of var is not clear in toy examples. in real life, people write stuff like

  Map<String, MyExtremelySpecificAndVeryLongTypeName> myExtremelySpecificAndVeryLongTypeNameMap = myExtremelySpecificAndVeryLongTypeNameMapProvider.provide();

literally anything to reduce the number of line breaks needed for a single statement is welcome.

[matt2000]

I agree, and I'm not sure how something like 'var accounts = calculateAccounts(something)' can be thought of as better in a code review setting. I suspect using "var" or equivalent will be considered a problem by most companies within the next few years.

[tombert]

This experiment has already been run with pretty much every language that isn’t Java or C, and I think most people have been ok.

Yes, code review is arguably worse, but most people who write Java do so with an IDE and the type is never unknown at that point.

Also, if your function is big enough to where the type of var is not very clear, it likely shouldn’t be passing code review regardless.

[nunobrito]

Those writing in python and javascript don't honestly know any better. They grew in a world without unit testing or without products that need to grow into gigantic systems maintained over the next decades.

This reminds me of a developer writing in jRuby because "it was better". While he was in the company he'd still give support to his own works, after leaving nobody else wanted to pickup those "better" things and would prefer to write workarounds to the tool, it effectively became a black box that few could improve and even worse to test. As result, those portions had to be rewritten in proper Java so that we'd be able to deeply measure/test and improve.

Never again.

[vips7L]

There’s nuance in programming. Both of these statements can be true. Var reduces boiler plate when you’re duplicating information in both the lvalue and rvalue.

I’m in agreement that when the information isn’t in the rvalue that you shouldn’t use var.

[jfengel]

Var can help in maintenance. Change the return type of calculateAccounts and you don't have to modify this code (assuming that it duck-types out equivalently).

That isn't necessarily a huge win: it does force a compile change that isn't obvious from the source. And a refactoring tool could have performed the code change automatically so it's not as big a deal as it might have been.

[matt2000]

I would argue that it helps me when performing maintenance to see and correct where types may have changed. Not always, and sometimes it is busy work I agree, but overall I prefer it.

[cokely]

Yeah I generally avoid using 'var' to elide method return types for that reason. In my early phase of var enthusiasm I even had it result in a bug that would have been caught if the type had been made explicit.

I do still really like it in the `var list = new ArrayList<String>()` case though.

[watwut]

Modify it when? If the interface renames? IDE does that. If the actual return type changes? They you do have to check that place whether it is still valid.

Maintenance involves a lot of reading of unknown code. That is literally the situation where you are rewiting var to specific types to figure out what is going on.

[jauntywundrkind]

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.

[Larrikin]

It is less readable because either accounts is named incorrectly or calculateAccounts is.

If it should be createAccounts, nothing is lost unless you have multiple account types in which case you would call it createUserAccounts, create adminAccounts etc.

[jghn]

> 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.

[pyrale]

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.

[nunobrito]

Oh man.. that comment really hit deep. I'll never understand why people argue that it is "easier" to adopt invisible characters and exact tab positioning instead of just using braces or similar to mark the code blocks.

Drives me nuts because you really can only write code for those programs with an IDE that is prepared for the case. Try to edit the code directly from the github web interface and it won't compile.

[vips7L]

> var accounts = calculateAccounts(something)'

Where did I write this? It’s almost as if there’s nuance in programming.

Var helps when you’re duplicating information that is already known. Your example is clearly not that.

[frje1400]

> You mention "var", why would we ever want in Java to hold a variable that you can't read immediately what is the type?

var items = new HashMap();

Instead of

HashMap items = new HashMap();

That's the point of var. It reduces noise a lot in some situations.

[vbezhenar]

You should write

    Map<String, Integer> 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 the language, as it's too dangerous and most people won't use it responsibly.

[tombert]

Your example isn’t good though; var is only for local variables, which should be perfectly allowed to use implementation-specific methods.

For argument types you don’t have var, so methods that take in a map can stay abstract and you can still pass in the implementation-specific version into those without casting it to the interface.

ETA:

I guess I am trying to say that if you want to be abstract, they should be at the argument or properties level. Local variables should be used locally. I agree that generally speaking you should try and prefer using Map for anything shared across different parts of code but I am not convinced it’s bad to have var be implementation-specific; if your method is big enough to where swapping out implementations like this will take a lot of time, your method is probably too big anyway.

[pico303]

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.

[jfengel]

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.

[pico303]

It’s not about swapping implementations, like the original poster suggested, so that you can later come in and swap out different implementations in a local sense. Interfaces are used to decouple parts of an application; for example mocking test interfaces. Another way to look at it is that interfaces are a contract that needs to be fulfilled.

Declaring a local variable as an interface to hide functionality so you can swap out functionality later is misunderstanding the fundamental theories around interfaces. Your variable should be whatever the function or method returns. If you want to abstract the type so it can be swapped out, create a function that returns an abstract type. Don’t tell the HashMap constructor it did the wrong thing. Now that I think about it, I’d recommend you use “var” in all cases, and not try to redefine the return values from a function.

[jsnsndn]

While I do use `var` when appropriate, your example is in general not appropriate

You would like to use Map<Key, Value> items = new HashMap<>() since in general you do not want implementation detail leaking into contracts

[vips7L]

Using var there doesn’t leak any implementation details into any contracts. Var is for local variables inside of functions. There are no details or contracts there.

[javanonymous]

> why would we ever want in Java to hold a variable that you can't read immediately what is the type

I can use my IDE to see the type if necessary.

> Everything that came after isn't really memorable nor helpful,

There are several improvements that are very helpful

One example is how multi line strings help me to read more clearly without the unnecessary string concatenations:

   var sql = """
             SELECT foo
             FROM bar
             WHERE last_updated > :lastUpdated
             """;

Another example is how switch statements have improved code readability, at least from my personal subjective viewpoint.

   String dayName = switch (day) {
      case 1 -> "Monday";
      case 2 -> "Tuesday";
      case 3, 4, 5 -> "Other day";
      default -> "Weekend";
   };

[nunobrito]

You could have as easily used String instead of var and there would be no ambiguity. This gets worse for numbers where it is important to know if you are dealing with an integer, long or something even bigger.

I agree with you on switches and do like the """ feature, thought. It was a real pain in the rear to include the multiple + "\n" back in the old days. This is a very clean and intuitive improvement.

[delusional]

> You mention "var", why would we ever want in Java to hold a variable that you can't read immediately what is the type?

I've been a full time java developer for the past 7 years. Let me start by agreeing that I have very little interests in the functional "innovations" they added. They're fine, but most of my colleagues agree that code using streams or lambdas very quickly becomes harder to debug then if you just wrote the code with loops and.

That's far from true for every java feature though. Switch statements have been super cool, Green threads are a promising road out of the CompletionStage hell the children are dreaming of these days. "var" is a very nice way to reduce double typing ("Thing x = new Thing()" -> "var x = new Thing()") and also a nice way to avoid changes to unrelated files ("Thing x = getFoo(); f(x);" -> "var x = getFoo(); f(x)" means changing the name of class Thing doesn't require any change to the code) that's been helpful in a lot of cases.

[nunobrito]

Yes, please don't get me wrong. There are always a few good things, but like you mention with streams: the person writing it can have an idea of what he was doing but the others afterwards will struggle to make changes and will likely revert the code base to simpler code.

Switch statements got better. I'm also getting used to Paths albeit don't yet understand why File wasn't already good enough. It is difficult to find compelling reasons for upgrading the JDK since I know it will be hassle for everyone that later down the line has to install/run the product.

[Sharlin]

If I had to guess, I'd say that a vastly bigger problem in the world is legacy code written in decades-old obsolete and inconvenient language dialects than code that's "too new".

[tombert]

I do not want to be rude but I am going to be: this entire comment illustrates my point very well. Instead of trying to actually learn new stuff, you say that the language peaked thirteen years ago.

> Everything that came after isn't really memorable nor helpful, especially lambdas.

Lambdas came out in Java 8, along with the streams API, and the fact that you don’t think they’re useful more demonstrates to me that you don’t actually understand it, since nearly every language before and after Java has lambdas and nearly everyone agrees that they’re useful.

Reifying a bunch of temporary interfaces is not “more readable” than a lambda. A bunch of terrible nested for-loop logic is not “more readable” than the streams API.

> You mention "var", why would we ever want in Java to hold a variable that you can't read immediately what is the type?

Your IDE can show the type, but even disregarding that there are lots of cases where you have to write the type twice in Java and it just makes noise. It doesn’t make the code more readable.

> we don't want to follow the same route of other programming languages unable to handle gigantic and complex platform systems.

Burying your head in the sand and Ignoring improvements in the language doesn’t make you more able to handle complex problems. It actually does the opposite and that’s so plainly obvious that I don’t think you actually thought through the sentence before you wrote it.

Take something like virtual threads. Most Java programmers don’t use them and instead keep using an executor service incorrectly because they also never learned the difference between blocking and non blocking IO. For them, virtual threads would be strictly better because it properly parks blocking IO.

Ultimately, I guess I disrespectfully disagree that Java “peaked” in 2012.

[deknos]

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.

[pyrale]

> 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.

[plasma_beam]

I view this largely as a symptom of the widescale “success” of the bloated J2EE app servers in the early 2000s to mid 2010s. Your Java version and dependencies were locked in and upgrading was a massive effort. A large group of developers stagnated on Java 1.4.2 and 5 and seemingly never updated their use of the language, even when moving to Java 8 and beyond. The legacy stuff keeps ticking along.

[tombert]

I kind of think thats backwards. I think the success of the abomination that we have decided to label as J2EE or Jakarta was attractive to intellectually unambitious Java engineers because it progressed so slowly.

I think people here are really underestimating how intellectually lazy most people are at their jobs. HN selection-biased for a geekier crowd so a lot of my criticisms don’t apply to readers of this forum.

[3036e4]

Sorry, but I don't think a preference for slow evolution is always because of laziness. What's wrong with wanting to keep improving on a skill instead of having to waste time relearning things every six months?

Software is rare among arts/crafts/whatever in that it is difficult to find nice areas of software to keep digging deeper into (as curious people do!) rather than having to move on to something new just when you start to be good something.

It's not even wanting to focus on depth instead of breadth, as the constant changes means you are barely able to keep using your older skills, so there is little actual breadth more like constantly moving between shallow pools of knowledge. Maybe it feels great to constantly be moving, but I do not see how it is productive or positive in any way for us.

[tombert]

I am arguing that they aren’t improving their skills in any regard, including how to properly use the tools they already pretend to know. They don’t go “deep” or “broad”, they don’t learn anything more than what they were taught in university.

I have had to debug a lot of concurrent Java, so my opinions are skewed towards that, but I have seen cases where “staff engineers” label every single function as `synchronized`, who genuinely don’t know why you would use a queue, have no concept of thread starvation or fairness, when to use an atomic instead of a mutex, and genuinely do not seem to understand that for network applications it’s generally more important to figure out how to reduce latency than trying to choose the optimal hashmap or sort implementation. These aren’t arcane details that require a PhD in category theory or require being constantly plugged into hacker news, these are extremely basic things that these Java engineers do not know.

I think most Java engineers, like more professionals in general, are very bad at their jobs. I think Java just selection-biases higher than other languages for people who are bad at their jobs.

[pyrale]

Yeah, people often underestimate the importance of community when they discuss programming language. In fairness to the Java crowd, you rarely see codebases looking like the team was trying to fit every new concept from some blog they read somewhere in the codebase, like you do in e.g. Scala or Haskell.

[latchkey]

> The biggest issue, though, is that Java programmers won’t use the new features.

My old CTO boss swore he wouldn't ever use annotations because they were too much magic for him.

"No! Writing out gobs of XML to configure Spring DI is the only way!"

[tombert]

I generally hate when people use the “magic” excuse for not doing things. Most of these tools are open source and/or can be readily viewed in IntelliJ. It really isn’t hard…cmd+click on what you want to look at.

If you’re an engineer you should be able to easily read the code to see what’s going on. Most of the time the “magic” can be understood in less than 30 minutes and then it’s not magic anymore.

[latchkey]

You're right, "magic" is generally when someone doesn't take the time to understand things. A busy CTO may not have time, so more things seem like magic to them.

What's inexcusable is to inflict the rest of your team with your nonsense.

[tombert]

Yep, completely agree.

I got in a bit of a disagreement with teammates at a previous job. I liked these teammates, they were very smart and nice people, but for a specific project I wanted to use LMAX Disruptor, and the excuse for not using it was very literally “we don’t want to make people learn anything”.

That stuff blows my mind; aren’t we engineers? If we’re not willing to learn new things and adapt, what exactly are we offering that a high school kid who bought an “Intro to Java” and “Intro to Spring” book can’t?

[kleyd]

I wouldn't dare say XML is better in this regard, but a good reason to be conservative with the use of annotations is exactly that cmd+clicking them doesn't easily lead to where the behavior is implemented.

[tombert]

Yeah, fair enough, though it's still not too hard to find where the behavior is implemented if you have access to the source code.

But you're right, cmd+clicking on the annotation just shows where the annotation is defined, not where the behavior is implemented.

[latchkey]

Sure. It is just another keyboard command in IDEA.

[whobre]

I don’t use Java often, but many developers at my workplace do; they universally hate the new FP features.

[Larrikin]

I thankfully have not had to use Java for years, but at one of my first jobs after grad school I was hired because I had Kotlin experience and they were moving the code base away from Java.

A few of the older developers also complained about the use of map, filter, zip, lambdas, etc being harder to read as well. Then a month or two later when they realized they weren't going away, it was an important part of the language, and just learned how to use them the complaints just one day stopped.

Except for when we had to touch Java code and it didn't make sense to convert it fully to Kotlin.

[jghn]

And then there are those of us who have used Java for a long time who feel the FP features make Java tolerable.

[tombert]

This is precisely my point. For a lot of Java programmers anything that they didn’t learn in university is “bad”, as far as I can tell, purely because they don’t want to actually learn new things.

They’ll give half-hearted justifications that are usually reductive or just flat out lies [1], but ultimately it seems to boil down to new=bad.

The amount of terrible code I have had to debug because Java programmers haven’t figured out you can use queues is upsetting, because all they learned in university is how to use `synchronized` wrong.

[1] I have learned that nearly every time someone says their disgusting code is “faster”, even when they claimed they tested it, it is almost universally untrue when I write a microbenchmark to check it.

[vips7L]

Everyone seems to love them at my workplace and in /r/java.

[vbezhenar]

That's called selection bias for both of you. Reddit will expel anyone whose opinion does not correspond to the local mob bias. Workplaces select people who are similar to already working ones.

[vips7L]

I’m well aware. I can still offer the contrary point of view.

[santiagobasulto]

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?

[jfengel]

Maven still sucks.

IntelliJ IDEA is genuinely great. It helps that they were the ones who developed Kotlin, and a fair bit of the actual language changes were gacked from Kotlin. (Or you could say "prototyped and shown valuable in Kotlin".)

They are still hampered by lousy nullable support.

You didn't ask, but Spring still sucks. It's not part of the language but it's a ubiquitous framework.

[tombert]

It’s amazing that Java has access to really great, high performing web toolkits like Vert.x and even Play, and yet the entire enterprise Java world has converged on Jakarta and Spring. I don’t like Spring but in my mind there is a special place in hell for Jakarta/JavaEE.

[fru654]

What’s wrong with Jakarta? (Genuinely curious)

[tombert]

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.

[vips7L]

Maven is generally fine. The only complaint anyone has is “xml bad”. Outside of that maven is probably (?) better than gradle. At least it prevents a custom scripting mess.

[Xenoamorphous]

What do you think of “modern” Javascript to write FP?

[tombert]

I haven’t touched much modern JS. I have done some TypeScript in the last few years but of course that’s a transpiled thing. I think TS isn’t too bad to write functional stuff though I have no idea if people actually enjoy reading my code.

[golyi]

var was introduced in Java 10 not 8.

[tombert]

Yep, just looked it up and you are right! I misremembered. I stand by my overall point though.