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j2objc
Java2014–2024
google / j2objc

j2objc

A Java to iOS Objective-C translation tool and runtime.

Languages & CompilersMobile & Desktop
Explore on GitHubRead Hacker News discussions
15Distinct people
15Mentions
0Explicit recommenders
6KGitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

A Java to iOS Objective-C translation tool and runtime.

GitHub

Where it is used

No documented product use was verified in the last source check.

What people are saying

No recommendation phrase was found in the indexed comments.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

No other repository is repeatedly linked in the same discussions.

This week on Hacker News

Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 12:24:10 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by year15 dated mentions

Observed mentions: 2014-03-18 21:34:31 UTC to 2024-06-27 16:05:32 UTC.

02462014-01-01 00:00:00 UTC to 2015-01-01 00:00:00 UTC (exclusive): 6 mentions; 1 submissions, 5 comments20142015-01-01 00:00:00 UTC to 2016-01-01 00:00:00 UTC (exclusive): 2 mentions; 0 submissions, 2 comments2016-01-01 00:00:00 UTC to 2017-01-01 00:00:00 UTC (exclusive): 3 mentions; 1 submissions, 2 comments2017-01-01 00:00:00 UTC to 2018-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2018-01-01 00:00:00 UTC to 2019-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2019-01-01 00:00:00 UTC to 2020-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments20192020-01-01 00:00:00 UTC to 2021-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2021-01-01 00:00:00 UTC to 2022-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2022-01-01 00:00:00 UTC to 2023-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2023-01-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-01-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 2 mentions; 1 submissions, 1 comments2024

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
20142014-01-01 00:00:00 UTC2015-01-01 00:00:00 UTC615
20152015-01-01 00:00:00 UTC2016-01-01 00:00:00 UTC202
20162016-01-01 00:00:00 UTC2017-01-01 00:00:00 UTC312
20172017-01-01 00:00:00 UTC2018-01-01 00:00:00 UTC101
20182018-01-01 00:00:00 UTC2019-01-01 00:00:00 UTC000
20192019-01-01 00:00:00 UTC2020-01-01 00:00:00 UTC000
20202020-01-01 00:00:00 UTC2021-01-01 00:00:00 UTC000
20212021-01-01 00:00:00 UTC2022-01-01 00:00:00 UTC000
20222022-01-01 00:00:00 UTC2023-01-01 00:00:00 UTC101
20232023-01-01 00:00:00 UTC2024-01-01 00:00:00 UTC000
20242024-01-01 00:00:00 UTC2025-01-01 00:00:00 UTC211

What Hacker News says

15 sources
thesuperbigfrog·Jul 9, 2022
>> 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
Read the rest
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.
In Microsoft begins “Extinguish” phase of dealing with Open Source
__sr__·Aug 9, 2017
I think it is best to write the "core" of your application using a language that can run on all of your target platforms -- which typically means you'll have to use C/C++/Rust or something similar that can be compiled to native code and supports somewhat sane FFI. The UI for each platform should be done using the Native UI toolkit for the platform. That way, you can avoid most of the code duplication. If you plan to target Android, you might want to check out Google's Java to Objective-C transpiler[1]. That will let you write the core of the app in Java and transpire it to Objective-C for iOS and macOS. The UI will still have to be written using the native toolkit for the platform, though. Fair warning: I have no idea how good or bad it is -- never used it myself. [1] https://github.com/google/j2objc
In Swift 5: start your engines
kyrra·Feb 4, 2015
How Google Inbox does it: Java and GWT There was a presentation at GWTCreate where Ray Cromwell laid out some of the magic on how they used GWT to handle this. The slides for the talk are here[0]. One of the key pieces here is that coding in Java gets you the web (with GWT), Android, and iOS using j2objc[1]. They posted a demo app showing this off[2]. The videos aren't up for the talks yet, but the Keynote from GWTCreate is posted (Ray gave that talk as well)[3]. [0] http://goo.gl/5zNFEm [1] https://github.com/google/j2objc [2] https://github.com/Sfeir/jhybrid [3] http://gwtcreate.com/videos/
In How Google Inbox shares 70% of its code across Android, iOS, and the Web
bad_user·Mar 18, 2014
> Couple that with the fact that he saw C# and .NET for what it was, Java done right C# has been a step up over Java, while .NET went in the other direction, getting all the things that Java got right backwards. In spite of .NET being heralded as the second coming of Java back in 2003, Java is stronger than ever and the ecosystem is probably much bigger than .NET will ever be. The problem that Microsoft always had, and I don't fully understand the dynamics at play here, is with the ecosystem they've grown. Whether this was on purpose, or due to platform limitations, or it just happened because they attracted the wrong kind of expectations, or maybe because of cultural issues, is up for debate. But the fact is the ecosystem is extremely weak and filled with snake oil offerings, with .NET developers waiting for Microsoft to throw solutions
Read the rest
over the wall for everything, while complaining about Java's fragmentation, when in fact Java's fragmentation is its bigger strength, as it's based on open-source that survives and competes and evolves and is a much healthier situation than the clusterfuck that happens when a paternalistic company is in charge, like with Windows Forms/XAML/Silverlight/HTML5. Yes, Java as a language sucks, but focusing on that while ignoring the JVM and the whole ecosystem around it is a pretty shallow comparisson. Hats off to Miguel, he saw something that he liked and built his own version. But for devs looking to make choices, without imposed constraints, picking .NET over Java makes no sense whatsoever. Even the original motto, with .NET being a runtime for multiple languages whereas Java was a language for multiple platforms proved in the end to be false. The JVM is not only multi-platform, but technically speaking it is much better at hosting other languages, with proof being the alternative languages implementations such as Clojure, Scala, JRuby, Jython, Groovy and Rhino, all of them popular and with healthy communities. Here's what Erik Meijer has to say about Scala, btw: https://twitter.com/headinthebox/status/438355100310831104 Here's what the Java ecosystem routinely does, as open-source: http://www.robovm.com/ ; http://oss.readytalk.com/avian/ ; https://github.com/google/j2objc And here's the best IDE ever, coming from the same people that are making Visual Studio usable: http://www.jetbrains.com/idea/
In Sources: Microsoft In Talks To Acquire Mobile App Development Startup Xamarin

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