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A categorized list of all Java and JVM features since JDK 8 to 16

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Re: A categorized list of all Java and JVM features since JDK 8 to 16

#81

Post by hibbelig »

voidfunc wrote: post #28
laurent92 wrote: post #17

Earlier quoted context omitted.

“Java is a big DSL to transform XML into stacktraces” — so was the joke at the time when domain-specific languages were the hype. This, and the FizzBuzz, Enterprise Edition: https://github.com/EnterpriseQualityCoding/FizzBuzzEnterpris... More seriously, what are you missing in Go that is well-done in Java? I assume verbosity of the code is still the defining characteristic of Java?

> More seriously, what are you missing in Go that is well-done in Java? 1. Generics. And yea, I know Go is getting generics "Real Soon Now" (tm), but it is incredibly annoying to write the same collection code over and over and there's some third-party libs that would really benefit from generics (looking at you Azure Go SDK). 2. Error handling... with the big caveat that I actually like Go's error handling mechanism…

About verbosity: you needed to define classes for so many things. Eg you want others to hook into processing in certain places. So you create a listener interface with some methods. And the provider needed to work with those, and the consumer also needs to work with them.

In modern Java maybe you can make do with functional interfaces and lambda, but it doesn’t always work I think.

And in emacs: the provider does run-hooks, and the consumer defines a function and says add-hook. Done. Very little ceremony.

Re: A categorized list of all Java and JVM features since JDK 8 to 16

#83

Post by halfmatthalfcat »

pcl wrote: post #55
wiradikusuma wrote: post #36

After a long stint with Scala, I recently came back to Java because I'm setting up a team for a greenfield project. Java has a good balance for ease of use, type safety, massive+mature ecosystem, and talent pool. The new language features (post v5) and framework maturity help reduce the "bloated" feeling that made me switch to Scala. Still not happy with the semicolon.

You might consider Kotlin then. It’s more JVM-aligned than Scala, but waaaay terser than Java (as yet — the Java team is making great strides).

What do you mean by "JVM-aligned" and how is Kotlin more JVM-aligned than Scala? Speaking as someone who uses Scala on a daily basis and never touched Kotlin.

Re: A categorized list of all Java and JVM features since JDK 8 to 16

#84

Post by Thaxll »

voidfunc wrote: post #13

Java gets a bad rap from people that used it late 90's through early 2000's and got burned out by XML and design pattern heavy frameworks but its a lovely language that with a little discipline can be used to create very lean looking code. Go is one of the HN darling languages and I work in Go everyday for work (and generally like it), but I really wish I could reach for Java most days.

"Go is one of the HN darling languages"

It's def not the case, I spend too much time here and on Reddit and people are always complaining about Go ( generics, errors, type system etc ... ), if you want the godly language it would be Rust, anything about Rust will be upvoted.

As for Java, it's a good language / runtime that is overly complicated behind layers of abstraction. Take Spring for examnple, magic everywhere, add an anotation there and it does x.y.z, you can't see it in the code but it does something.

Re: A categorized list of all Java and JVM features since JDK 8 to 16

#85

Post by bluejekyll »

savanu wrote: post #77
wtetzner wrote: post #34

Earlier quoted context omitted.

Say you have: public void doSomething(Optional foo) { ... } You want `foo` to be `Optional.empty()` or `Optional.of("some string")`. The way things currently work, `foo` could also be `null`.

How does making Optionals allocated on the stack (value types) prevent this? Or rather why do you need value types to accomplish this?

Perhaps this example will make it more obvious:

    boolean truthy = false;
    truthy = null; // compilation failure, type mismatch
vs. the Boolean type

    Boolean truthy = new Boolean(false);
    truthy = null; // compiles just fine
The reason Boolean (and other boxed primitive types) exist is because it is an Object (a reference type) and that allows them to be used in things like collections that expect Objects and not primitive types.

Looking at https://openjdk.java.net/jeps/401 it's not totally clear to me at the moment how you can use ValueTypes (primitive keyword) in Collections. Might be that you'll need to take a reference to them with Type.ref (but I need to read 401 in more detail to understand that).

Hope that helps.

Re: A categorized list of all Java and JVM features since JDK 8 to 16

#86

Post by ragnese »

voidfunc wrote: post #13

Java gets a bad rap from people that used it late 90's through early 2000's and got burned out by XML and design pattern heavy frameworks but its a lovely language that with a little discipline can be used to create very lean looking code. Go is one of the HN darling languages and I work in Go everyday for work (and generally like it), but I really wish I could reach for Java most days.

I disagree that it's a lovely language. I think, as developers, we very quickly develop Stockholm syndrome. Once you "learn" a language, it's really easy to churn out code and apply idioms without even realizing that you're constantly writing workarounds and kludges for your language's deficiencies.

As a polyglot dev, the following are my gripes with Java:

* null - we all know, so I'm not going to bother expanding except to say that @NotNull is NOT a solution and it doesn't guarantee shit.

* interfaces are extremely lacking compared to type classes and lead to verbose and cumbersome patterns such as "Adapter".

* Type-erased generics. Why shouldn't I be able to implement a generic interface for multiple types? E.g., class MyNumber implements Comparable, Comparable, Comparable {}

* It only just got Records and sealed interfaces, so thank goodness for that. But prior versions of Java are extremely lacking in expressiveness without these.

* I don't hate checked exceptions as a concept, but the fact that you can't be "generic" over the exceptions in a function signature is frustrating. This is why everyone says they're "incompatible" with Java's closure APIs.

* No unsigned ints.

* Silent integer overflow/wrap-around. It's not C- did it really have to copy this insanity?

* Dates and timezones are still insane, even in Java 8+.

* The fact that arrays got type variance wrong.

* JDBC sucks. JPA also kind of sucks.

* No concept of `const` or immutability.

I'm not saying that Java is the worst language in the world or anything, but it's far from great, IMO. Most programming languages are pretty awful, IMO.

Re: A categorized list of all Java and JVM features since JDK 8 to 16

#87

Post by kaba0 »

Thaxll wrote: post #84
voidfunc wrote: post #13

Java gets a bad rap from people that used it late 90's through early 2000's and got burned out by XML and design pattern heavy frameworks but its a lovely language that with a little discipline can be used to create very lean looking code. Go is one of the HN darling languages and I work in Go everyday for work (and generally like it), but I really wish I could reach for Java most days.

"Go is one of the HN darling languages" It's def not the case, I spend too much time here and on Reddit and people are always complaining about Go ( generics, errors, type system etc ... ), if you want the godly language it would be Rust, anything about Rust will be upvoted. As for Java, it's a good language / runtime that is overly complicated behind layers of abstraction. Take Spring for examnple, magic everywhere,…

Java itself is most definitely not overly complicated. Many frameworks, and created programs are due to enterpriseTM software development, but it’s orthogonal. And spring is a really feature-packed framework which has a solution for almost every business problem that one can face. Of course it comes with a great deal of complexity, but it is a tradeoff. I rather tinker with how to use a given feature than implement it myself, often in an inferior way.

Re: A categorized list of all Java and JVM features since JDK 8 to 16

#88

Post by kaba0 »

halfmatthalfcat wrote: post #37
bluejekyll wrote: post #3

One of the primary features I'm holding out hope for eventually making it into the language is ValueTypes: http://cr.openjdk.java.net/~jrose/values/values-0.html and the current Valhalla Project: https://wiki.openjdk.java.net/display/valhalla/Main The simplest example of why this would be valuable (edit: this was not an intentional pun), the Optional type could become stack based, such that you could ensure that the…

Or use Scala :)

Which doesn’t have value types because it should be implemented in the JVM?

Re: A categorized list of all Java and JVM features since JDK 8 to 16

#89

Post by kerblang »

voidfunc wrote: post #28
laurent92 wrote: post #17

Earlier quoted context omitted.

“Java is a big DSL to transform XML into stacktraces” — so was the joke at the time when domain-specific languages were the hype. This, and the FizzBuzz, Enterprise Edition: https://github.com/EnterpriseQualityCoding/FizzBuzzEnterpris... More seriously, what are you missing in Go that is well-done in Java? I assume verbosity of the code is still the defining characteristic of Java?

> More seriously, what are you missing in Go that is well-done in Java? 1. Generics. And yea, I know Go is getting generics "Real Soon Now" (tm), but it is incredibly annoying to write the same collection code over and over and there's some third-party libs that would really benefit from generics (looking at you Azure Go SDK). 2. Error handling... with the big caveat that I actually like Go's error handling mechanism…

Sorry that I find it necessary for yet another answer to your verbosity question, but: The real verbosity is in the standard libraries. What would be a one-liner in any other language is usually at least 2, often 3, and sometimes enough that you end up writing your own wrapper function or library. Especially noticeable is the agony of Lists & Maps, which are first-class citizens in most languages (classic job interview question: what is the difference between ArrayList and LinkedList? Real answer: Nobody actually uses LinkedList).

The stdlib often seems to be written by people who had no intention of using it. I guess maybe this applies to C++ as well, so for some folks it seems normal.

Re: A categorized list of all Java and JVM features since JDK 8 to 16

#90

Post by aphexairlines »

brabel wrote: post #76
dlbucci wrote: post #29

All the backend projects I work on were originally written in Java. I'll admit that Streams and Lombok make it a somewhat pleasant experience to work with, at least compared to when I used it in college (I think Java 8 was newest?). But that said, I once tried writing a new feature in Kotlin, and now all our code is Kotlin. I don't really see how Java can compete with the non-nullable types, data classes, and type-in…

I write a lot of Kotlin code but still tend to use Java a lot. All of the features you mention are not really an advantage for Kotlin anymore. Java has had tools to deal with nulls for a long time, we tend to assume everything is non-null unless annotated with `@Nullable` and let tools check correct usage at compile time... data classes are very similar to Java 16's records. Type-inference since Java introduced `var`…

You can only assume non-null for your own code though. The java ecosystem of 3rd-party libraries will give you nulls, and most of the time won't include nullability annotations.

var is a nice step, but encourages mutability since it's not final by default.

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