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Comment by whartung | Hacker News Reader

  > Not only in regards to figuring out the language and resources available but also the fact that creating a GUI still requires external dependencies.

What external dependencies does Java need that's not in the JDK itself? I have an app with Mac and Windows installers (and thus bundles JDKs), it also runs on Linux (via a fat jar), I tested it on Ubuntu, but for the life of me I couldn't figure out how to package it properly. It was more complicated that I cared to invest it at the time.

As for the barrier to entry, I feel the same way about the web. I find the JS and Web ecosystem to be utterly overwhelming, one reason I stuck with Java over something like Electron, and the installers/footprint of the app are smaller to boot.

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For Linux, I'm using jpackage to package my Java software to .deb (x64 architecture) file. For all the other Linux variants, I've a .tgz file that contains the jar file, libraries and icons of the applications.

The problem I have with Linux is named at the end of the website: "Sharing your creation". It's pages and pages of documentation that is not relevant to the packaging of your application where you can spend hours of work without finding what you want of finding out that it doesn't work for you because for example it's not on GitHub. Hopefully jpackage was able to fix it for the .deb format. Instead of working on more documentation, working on better and easier to use packaging tool would help.

The JRE itself is an external dependency that you need to bunle because it is not part of most Linux distributions. And even if there is a JRE installed it is not guaranteed to be able to run your Java application.

https://github.com/hydraulic-software/eton-desktop

> What external dependencies does Java need that's not in the JDK itself?

I mean that it doesn't come with Java itself, but you as a developer need to pick a UI framework and not all of them actually work all that well cross platform or will get you an actual modern interface.

Edit: I should also note that the threshold for entry I am talking about is for people just generally starting out. There simply are way more resources available for web related development than there are for java.

Also, when you start bundling your JDKs I am not sure you can talk about a smaller footprint anymore.

> Also, when you start bundling your JDKs I am not sure you can talk about a smaller footprint anymore.

What, do you bundle Electron source and Electron build environment with your Electron app?

Why would you do the same and bundle Java source code + Java compilers in your Java app?

Why would you do the same and bundle <any language> source code + <any language> compilers in your <any language> app?

If you need to create a "just works without dependency b.s." experience in Java, you use the correct tooling for that, jlink.

> If you need to create a "just works without dependency b.s." experience in Java, you use the correct tooling for that, jlink.

At which point you are including a similar footprint as Electron does by shipping chrome. I mean, you must have realized I was talking about the inclusion of the JRE and whatever else is needed to make a java application run on a system as a standalone application.

So I am honestly not sure what you are arguing besides semantics.

Well, Swing is still bundled with Java. Netbeans uses the "Flat Look and Feel" and looks ok to me. I find Swing a lot more work compared to FX.

JavaFX used to be bundled with Java, but was removed. Some JDK distributions bundle FX like it was before, and adding FX to a new project is simple and straight forward. Maven packages it nicely, and it includes the platform specific binary parts. If you can use Log4j, you can use Java FX. Onboarding onto FX is not a high bar.

I can not speak to SWT.

There's several examples of "modern" UIs in FX, I can't speak to any of them, I don't pay much attention to that space. It's imperfect compared to the web, but not impossible.

Java FX seems better than swing, but it's an external dependency now though, isn't it? I thought it got removed from the jdk a few years ago.

It was. Even before it was more "bundled" with the JDK than "part of Java".

But, to be honest, that's a real nit. It's a standalone dependency, it's 4 lines in a POM file, it doesn't drag the internet with it, and it only relies on the JDK. So, while it's a large subsystem, it's a "low impact" dependency in terms of side affects and complexity.

> it's a "low impact" dependency in terms of side affects and complexity.

I wish that were true in my experience. But we have struggled to support {macOS, Windows, Linux} x {x86_64, arm64} with JavaFX and one .jar for our application.

This is a 250-line diff, not a 4-line diff: https://github.com/ra4king/CircuitSim/pull/93/files. We have to manually manage .dlls and .sos by hand.

If you know a solution that is 4 lines, we would be very grateful. All we want is one .jar with JavaFX in it that supports many OSs and architectures.

Not sure what your requirements are.

My point about 4 line dependency is to point out that the barrier to entry into FX is low. What you are doing I would consider unconventional, as demonstrated by all of the hoops you're jumping through to achieve it. Packaging, yes, is still a bit arcane at this point.

My project, https://github.com/willhartung/planet packages macOS and Windows installers, and can be run as a fat jar on a Linux machine (tested on Ubuntu). You can look in there to see my POM file, and my build scripts. They're much simpler than what you're doing. I don't have a package for Linux, as I mentioned earlier, it was just a bit to confusing to figure out Linux packaging for my tastes, so I punted. If there was crushing demand for it, I'd look into it deeper.

None of those artifacts are "cross platform". It's not a single artifact for all platforms, they are platform specific. I build the Mac one on my machine, and the Windows and Linux versions on VMs. Currently, the vision for Java distribution is to bundle the runtime with the application. Use jlink and the module system to narrow down your JRE, and jpackage to combine them into an appropriate, platform artifact. jpackage requires to be run on the host OSs. I do not have ARM versions of any of my code yet.

If you want to ship a cross platform jar, then it's probably worth your time to require a JDK with FX already installed. Azul does this, I think there are others. Then the FX, and it's platform specific binaries, are no longer your applications problem.

Also, there is a project, https://jdeploy.com that offers tooling and infrastructure to distribute native FX bundles, it even offers automatic updates. It will install its own JDK in its own directory structure to run your applications. If you have multiple applications, it will share the JDKs among them. It's quite clever, and perhaps worth considering depending on your requirements. I chose to not do that just to make my projects as simple as practical for the end user and myself.

I'll be fair, getting to this point was not drag and drop. jpackage and jlink can be fiddly to get started with. Documentation can always be better.

> What you are doing I would consider unconventional

It wasn't before JavaFX was removed from the Oracle JRE. That is my point. JavaFX used to be a trivial dependency, but now it is quite painful in otherwise identical configurations, definitely not "low-impact."

> If you want to ship a cross platform jar

We do. Isn't that the point of Java, "write once run anywhere"?

This program is also used as a library in autograders. We do not want to distribute 5 versions of each autograder for 2-4 assignments. The autograder should be distributed as 1 jar. Undergrad TAs are creating that jar and may not have knowledge of complex CI pipelines etc.

> then it's probably worth your time to require a JDK with FX already installed.

That is not appropriate here. This is an educational tool, and students are enrolled in other courses that use Java frequently. We should be able to use the same JRE that students already have installed — it is unreasonable to require installing a different third-party JRE to run a digital logic simulator. It also adds another hurdle for freshmen/sophomores who may not have a natural ability for juggling different JRE installations. (Source: We tried requiring Azul and it was painful for everyone.)

> I do not have ARM versions of any of my code yet.

We have >900 students in this class, so it is necessary to support M1/M2; in fact, a large portion of our students had M1/M2 laptops. It sounds to me like you could just provide a fat jar in your case, actually. Supporting aarch64 is where we hit problems with our fat jar[1], since the aarch64 native libraries have the same name as the x86_64 libraries.

To summarize my point: yes you can make the build/install process more convoluted and avoid this problem. But we have an installation flow that has been battle-tested by thousands of students for 13 years (download circuit simulator .jar and run it) we have no good reason to abandon. The combination of the arrival of M1/M2 and JavaFX getting yanked from the JRE has made supporting our existing (extremely reasonable) flow nothing close to "low-impact."

1: https://github.com/ra4king/CircuitSim/pull/93/files#diff-648...

Makes sense. I worked a bit with Java years ago, but never with GUI stuff. Most of what I remember about it was drowning in boilerplate and being really good for coordinating a lot of developers around a big well-organized codebase. I probably couldn't write hello world from scratch without reference if I was being held at gunpoint.

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