Codename One VS J2ObjC

codenameone.com — Open source, cross-platform, mobile app development toolchain for Java/Kotlin developers. Free for commercial use with an unlimited number of projects

This was resolved in this issue: https://github.com/codenameone/CodenameOne/issues/3706

Naturally depends on the use case, yet they work good enough to be in business for 20 years.

https://www.ptc.com/en/products/developer-tools/perc

https://www.aicas.com/wp/products-services/jamaicavm-tools/

https://www.codenameone.com/

Android 5 & 6 (only changed back into JIT/AOT due to long compile times), https://www.infoq.com/news/2014/07/art-runtime/

Unfortunely the best well known, Excelsior JET, is no longer in business, most likely due to GraalVM and OpenJ9 being available as free beer, while PTC, Aicas Codename One are safe in their domains.

There is also RoboVM (https://github.com/MobiVM/robovm) as free beer, however it actually started as a commercial product, and the acquisition from Xamarin kind of stagnated it (naturally).

At Codename One, we were using App Engine when our daily billing suddenly skyrocketed from a few dollars to hundreds. The potential cost was so high it threatened to bankrupt us within a month. Despite our best efforts, including educated guesses and fixing everything we could, we were never able to pinpoint the specific bug. Instead, we had to solve the problem through brute force.

We don't use GraalVM since our project was developed prior to its existence and we aimed for deeper native integration than it can offer: https://github.com/codenameone/CodenameOne

XMLVM, Codename One and iSpectrum (cross compile Java code from an Android app or creating one from scratch

I suggest filing an RFE in the issue tracker.

Thanks. It's always good to get another reminder. Yes, it was reported. u/shannah78 is working on this but we have time until November.

please check this issue https://github.com/codenameone/CodenameOne/issues/3686

We use ParparVM which we wrote. It compiles a subset of Java 8 (sort of) to native by translating the bytecode to C and passing that through XCode. The reason we took this path and not the path of "direct to native", is that it allows for future compatibility.

>> What is Java's equivalent of Xamarin or Avalonia?

Xamarin - RoboVM was a Java-based competitor to Xamarin which Xamarin acquired in 2015, but it was shutdown in 2017 after Microsoft acquired Xamarin. There are some Java-based toolkits such as https://www.codenameone.com/ that target mobile, but they are probably not as well funded as Xamarin has been under Microsoft. From what I hear Xamarin will be deprecated and replaced by MAUI.

Avalonia - Java has had multiplatform windowing for much longer than C# has. The Java Swing toolkit has been part of Java for more than a decade and is still supported in OpenJDK. JavaFX (https://openjfx.io/) is a newer toolkit that was originally part of Java and was later spun out into its own project.

How well are Xamarin and Avalonia supported if you are doing C# development on Mac or Linux?

>> How do I run Java on iOS?

As stated above, some tools such as https://www.codenameone.com/ and https://github.com/google/j2objc that convert Java code to target iOS.

I have never tried using those tools so I am not sure how good they are.