RFR: 8359396: [Linux] Require Gtk3 >= 3.20 for glass-gtk

[Kevin Rushforth]

On Fri, 13 Jun 2025 01:00:31 GMT, Thiago Milczarek Sayao <tsayao at openjdk.org> wrote:

> Upgrade the minimum required GTK version for JavaFX to GTK 3.20 to enable modern features and better Linux desktop integration.
> 
> JavaFX currently depends on GTK 3.8, [released](https://mail.gnome.org/archives/gtk-devel-list/2013-March/msg00108.html) in March 2013. This version is outdated and predates many useful GTK API improvements.
> 
> GTK 3.20 was [released](https://mail.gnome.org/archives/gtk-list/2016-March/msg00026.html) on March 21, 2016.
> 
> Updating the GTK minimum requirement to 3.20 would enable JavaFX to support new features, including the improvements proposed in  #1605 
> 
> Major Linux distributions already provide GTK 3.20 or newer:
> - Ubuntu LTS 18.04+ (ships GTK 3.22+)
> - Debian 9+ (ships GTK 3.22+)
> - Fedora 24+ (ships GTK 3.20+)
> - Oracle Linux and Red Hat Enterprise Linux 8+ (ships GTK 3.22+)

I ran a CI build including headful tests, and all looks good to me.

Running on a system (my old Ubuntu 16.04 box) with an older GTK3 fails with the expected error message:


Exception in thread "main" java.lang.reflect.InvocationTargetException
        at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:118)
        at java.base/java.lang.reflect.Method.invoke(Method.java:580)
        at java.base/sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:1164)
Caused by: java.lang.UnsupportedOperationException: Minimum GTK version required is 3.20.0. System has 3.18.9.
        at javafx.graphics at 25-ea/com.sun.glass.ui.gtk.GtkApplication._initGTK(Native Method)
        at javafx.graphics at 25-ea/com.sun.glass.ui.gtk.GtkApplication.<init>(GtkApplication.java:165)
        at javafx.graphics at 25-ea/com.sun.glass.ui.gtk.GtkPlatformFactory.createApplication(GtkPlatformFactory.java:40)
        at javafx.graphics at 25-ea/com.sun.glass.ui.Application.run(Application.java:143)
        ...


Compiling on a machine with an older GTK3 fails with the expected error message:


Starting process 'command 'pkg-config''. Working directory: . Command: pkg-config --exists gtk+-3.0 >= 3.20.0
Successfully started process 'command 'pkg-config''

FAILURE: Build failed with an exception.

* Where:
Script 'buildSrc/linux.gradle' line: 103

* What went wrong:
A problem occurred evaluating script.
> GTK3 3.20.0+ development packages not found. If GTK3 packages are installed, please remove the build directory and try again.


@tsayao The review likely won't be finished until Monday, but even if it is, please wait until then to give others time to comment.

I left one minor suggestion and will reapprove if you make changes.

@lukostyra Can you be the second reviewer?

@tiainen Do you also want a change to build it? I don't imagine it will cause you any problems, but wanted to give you a chance to comment.

buildSrc/linux.gradle line 28:

> 26: ext.LINUX = [:]
> 27: 
> 28: def gtk3MinMinorVersion = "20"

Minor: maybe add a comment saying that the minimum GTK3 version is 3.20?

-------------

Marked as reviewed by kcr (Lead).

PR Review: https://git.openjdk.org/jfx/pull/1825#pullrequestreview-2925521698
PR Comment: https://git.openjdk.org/jfx/pull/1825#issuecomment-2971031398
PR Review Comment: https://git.openjdk.org/jfx/pull/1825#discussion_r2145529940