Hi, I'm new to Greenfoot here. I know Java quite well and often make my own Java program and applications. But lately, I have encountered an annoying error. When I run the .jar file from File Explorer or the Command Prompt, it always shows me a dialog message saying "JNI Error" and I tried to fix it but nothing works. Maybe some of you can help me?
The error when trying to run it from Command Prompt:
Error: Could not find or load main class greenfoot.export.GreenfootScenarioApplication
Caused by: java.lang.NoClassDefFoundError: javafx/application/Application
And the ol' JNI Error:
Error: A JNI error has occurred, please check your installation and try again.
A Java exception has occurred.
Oh, and also..
Exception in Application start method
Exception in thread "main" java.lang.reflect.InvocationTargetException
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at java.base/sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:1051)
Caused by: java.lang.RuntimeException: Exception in Application start method
at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:900)
at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication$2(LauncherImpl.java:195)
at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: java.lang.NullPointerException
at greenfoot.core.ExportedProjectProperties.load(ExportedProjectProperties.java:63)
at greenfoot.core.ExportedProjectProperties.<init>(ExportedProjectProperties.java:52)
at greenfoot.export.GreenfootScenarioViewer.<init>(GreenfootScenarioViewer.java:138)
at greenfoot.export.GreenfootScenarioApplication.start(GreenfootScenarioApplication.java:39)
at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$9(LauncherImpl.java:846)
at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runAndWait$12(PlatformImpl.java:455)
at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$10(PlatformImpl.java:428)
at java.base/java.security.AccessController.doPrivileged(Native Method)
at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$11(PlatformImpl.java:427)
at javafx.graphics/com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:96)
at javafx.graphics/com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at javafx.graphics/com.sun.glass.ui.win.WinApplication.lambda$runLoop$3(WinApplication.java:174)
... 1 more
