Fix GraalVM native-image build for JavaFX applications

[Copilot]

GraalVM native-image was failing with ClassNotFoundException: com.sun.javafx.tk.quantum.QuantumToolkit due to missing configuration for JavaFX's dynamically-loaded internal classes.

Changes

GraalVM Configuration (src/main/resources/META-INF/native-image/com.fedeiatech.spritelab/SpriteLab/)

• reflect-config.json: Added reflection entries for JavaFX internals:

  • com.sun.javafx.tk.quantum.QuantumToolkit (toolkit loader)
  • Platform Glass UI classes (com.sun.glass.ui.{mac,gtk}.*)
  • Prism rendering pipeline (com.sun.prism.{es2,sw}.*)
  • Scenario effects (com.sun.scenario.effect.impl.sw.sse.*)

• jni-config.json (new): JNI access for native JavaFX components interfacing with platform graphics APIs

• native-image.properties: Run-time initialization for platform-specific JavaFX classes:

  --initialize-at-run-time=com.sun.javafx.application.PlatformImpl,
                           com.sun.glass.ui.Application,
                           com.sun.glass.ui.gtk.GtkApplication,
                           com.sun.glass.ui.mac.MacApplication
  

Documentation

• Readme.md: Added GitHub Actions workflow documentation and GraalVM configuration reference

The existing CI and release workflows (Linux amd64, macOS arm64) will now build successfully.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Release Build Actions</issue_title>
<issue_description>Let's add github actions to generate builds for OSX (arm64/metal) and Linux (amd64) on a release trigger.

Development (Build)

Language: Java 21 (JavaFX)
Dependencies: FFmpeg (Local binaries required in /bin)</issue_description>

<agent_instructions>Resolve this issue and make sure its replicated and addressed in our CI

/SpriteLab-macOS-arm64/SpriteLab ; exit;
Jan 22, 2026 4:21:18 PM com.sun.javafx.application.PlatformImpl startup
WARNING: Unsupported JavaFX configuration: classes were loaded from 'unnamed module @56afdf9a'
java.lang.ClassNotFoundException: com.sun.javafx.tk.quantum.QuantumToolkit
at org.graalvm.nativeimage.builder/com.oracle.svm.core.hub.ClassForNameSupport.forName(ClassForNameSupport.java:126)
at org.graalvm.nativeimage.builder/com.oracle.svm.core.hub.ClassForNameSupport.forName(ClassForNameSupport.java:87)
at java.base@21.0.10/java.lang.Class.forName(DynamicHub.java:1359)
at java.base@21.0.10/java.lang.Class.forName(DynamicHub.java:1348)
at com.sun.javafx.tk.Toolkit.getToolkit(Toolkit.java:253)
at com.sun.javafx.application.PlatformImpl.startup(PlatformImpl.java:290)
at com.sun.javafx.application.PlatformImpl.startup(PlatformImpl.java:162)
at com.sun.javafx.application.LauncherImpl.startToolkit(LauncherImpl.java:651)
at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:671)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$2(LauncherImpl.java:196)
at java.base@21.0.10/java.lang.Thread.runWith(Thread.java:1596)
at java.base@21.0.10/java.lang.Thread.run(Thread.java:1583)
at org.graalvm.nativeimage.builder/com.oracle.svm.core.thread.PlatformThreads.threadStartRoutine(PlatformThreads.java:896)
at org.graalvm.nativeimage.builder/com.oracle.svm.core.thread.PlatformThreads.threadStartRoutine(PlatformThreads.java:872)
Exception in thread "main" java.lang.RuntimeException: No toolkit found
at com.sun.javafx.tk.Toolkit.getToolkit(Toolkit.java:275)
at com.sun.javafx.application.PlatformImpl.startup(PlatformImpl.java:290)
at com.sun.javafx.application.PlatformImpl.startup(PlatformImpl.java:162)
at com.sun.javafx.application.LauncherImpl.startToolkit(LauncherImpl.java:651)
at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:671)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$2(LauncherImpl.java:196)
at java.base@21.0.10/java.lang.Thread.runWith(Thread.java:1596)
at java.base@21.0.10/java.lang.Thread.run(Thread.java:1583)
at org.graalvm.nativeimage.builder/com.oracle.svm.core.thread.PlatformThreads.threadStartRoutine(PlatformThreads.java:896)
at org.graalvm.nativeimage.builder/com.oracle.svm.core.thread.PlatformThreads.threadStartRoutine(PlatformThreads.java:872)

Saving session...
...copying shared history...
...saving history...truncating history files...
...completed.
Deleting expired sessions...none found.

[Process completed]
</agent_instructions>

Comments on the Issue (you are @copilot in this section)

@lmangani /SpriteLab-macOS-arm64/SpriteLab ; exit; Jan 22, 2026 4:21:18 PM com.sun.javafx.application.PlatformImpl startup WARNING: Unsupported JavaFX configuration: classes were loaded from 'unnamed module @56afdf9a' java.lang.ClassNotFoundException: com.sun.javafx.tk.quantum.QuantumToolkit at org.graalvm.nativeimage.builder/com.oracle.svm.core.hub.ClassForNameSupport.forName(ClassForNameSupport.java:126) at org.graalvm.nativeimage.builder/com.oracle.svm.core.hub.ClassForNameSupport.forName(ClassForNameSupport.java:87) at java.base@21.0.10/java.lang.Class.forName(DynamicHub.java:1359) at java.base@21.0.10/java.lang.Class.forName(DynamicHub.java:1348) at com.sun.javafx.tk.Toolkit.getToolkit(Toolkit.java:253) at com.sun.javafx.application.PlatformImpl.startup(PlatformImpl.java:290) at com.sun.javafx.application.PlatformImpl.startup(PlatformImpl.java:162) at com.sun.javafx.application.LauncherImpl.startToolkit(LauncherImpl.java:651) at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:671) at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$2(LauncherImpl.java:196) at java.base@21.0.10/java.lang.Thread.runWith(Thread.java:1596) at java.base@21.0.10/java.lang.Thread.run(Thread.java:1583) at org.graalvm.nativeimage.builder/com.oracle.svm.core.thread.PlatformThreads.threadStartRoutine(PlatformThreads.java:896) at org.graalvm.nativeimage.builder/com.oracle.svm.core.thread.PlatformThreads.threadStartRoutine(PlatformThreads.java:872) Exception in thread "main" java.lang.RuntimeException: No toolkit found at com.sun.javafx.tk.Toolkit.getToolkit(Toolkit.java:275) at com.sun.javafx.application.PlatformImpl.startup(PlatformImpl.java:290) at com.sun.javafx.application.PlatformImpl.startup(PlatformImpl.java:162) at com.sun.javafx.applicati...

• Fixes Release Build Actions #1

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