java - Swing 应用程序的 Graal native 图像 : Detected a started Thread in the image heap

Question

public class SimpleApp {
    public static void main( String[] args ) {
        JOptionPane.showMessageDialog(null, "Ciao", "Info", JOptionPane.INFORMATION_MESSAGE);
    }
} 

当我尝试使用 native-image --no-fallback 创建原生图像时，我得到了这个:

Error: Detected a started Thread in the image heap. Threads running in the image generator are no longer running at image run time. The object was probably created by a class initializer and is reachable from a static field. By default, all class initialization is done during native image building.You can manually delay class initialization to image run time by using the option -H:ClassInitialization=. Or you can write your own initialization methods and call them explicitly from your main entry point.

Detailed message: Trace: object sun.java2d.opengl.OGLRenderQueue field sun.java2d.opengl.OGLRenderQueue.theInstance

Answer 1

这都与何时应该初始化一个类有关——GraalVM 团队有一篇关于这个主题的更新文章: https://medium.com/graalvm/updates-on-class-initialization-in-graalvm-native-image-generation-c61faca461f7

简短版本:使用跟踪(在比您的版本更新的 Graal 包版本中添加)找到所谓的有问题的类，然后将它们设置为在运行时初始化。说起来容易，做起来难。对于它的值(value)，我只是在 19.2(企业)版本和一些包含 AWT 的随机代码中遇到了同样的问题。不过，消息已更改(为清楚起见略作编辑):

Error: Detected a started Thread in the image heap. Threads running in the image generator are no longer running at image run time. To see how this object got instantiated use -H:+TraceClassInitialization. The object was probably created by a class initializer and is reachable from a static field. You can request class initialization at image run time by using the option --initialize-at-build-time=<class-name>. Or you can write your own initialization methods and call them explicitly from your main entry point.
Trace: object sun.awt.AWTAutoShutdown
method sun.awt.AWTAutoShutdown.getInstance()

我会解决这个问题(可能从 AWT 等同于“Hello World”开始，如果我成功了，我会用具体细节更新我的答案。Google 上到处都是原生图像无法与 Swing/AWT/JavaFX 一起工作的示例, 所以我不确定我会成功。

免责声明:我在 Oracle 工作，但不在与 Graal 开发人员关系密切的组织中(可能没有共同的经理)。我说的任何话都是我的意见。