JavaFX with maven - Exception in Application start method (InvocationTargetException + RuntimeException + IllegalAccessError)

Question

I am beginning learning with JavaFX but I am having issues to set up properly the project. I have been following a tutorial in order to learn how JavaFX works but when I run the project I get errors I do not know how to solve.

I have been looking for people getting the same error and I found one in stackoverflow but I have the feeling that does not correspond to my issue.

Please, may you help me ?

Thank you in advance

package com.mathieuascain.javafxtutorial;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;

public class Main extends Application {

    Button button;

    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage primaryStage) throws Exception {
        primaryStage.setTitle("My first JavaFX GUI");

        button = new Button();
        button.setText("Click me");

        StackPane layout = new StackPane();
        layout.getChildren().add(button);

        Scene scene = new Scene(layout, 300, 250);
        primaryStage.setScene(scene);
        primaryStage.show();
    }
}

Pom configuration

<?xml version="1.0" encoding="UTF-8"?> 

<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.mathieuascain</groupId>
    <artifactId>javafx-tutorial</artifactId>
    <packaging>jar</packaging>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.14</maven.compiler.source>
        <maven.compiler.target>1.14</maven.compiler.target>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.openjfx</groupId>
            <artifactId>javafx-controls</artifactId>
            <version>16</version>
        </dependency>
        <dependency>
            <groupId>org.openjfx</groupId>
            <artifactId>javafx-maven-plugin</artifactId>
            <version>0.0.5</version>
            <type>maven-plugin</type>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.openjfx</groupId>
                <artifactId>javafx-maven-plugin</artifactId>
                <version>0.0.5</version>
                <configuration>
                    <mainClass>com.mathieuascain.javafxtutorial.Main</mainClass>
                </configuration>
            </plugin>
        </plugins>
    </build> 
</project>

Compiling errors :

Exception in Application start method
java.lang.reflect.InvocationTargetException
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:567)
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:464)
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:363)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:567)
    at java.base/sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:1071)
Caused by: java.lang.RuntimeException: Exception in Application start method
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:900)
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication$2(LauncherImpl.java:195)
    at java.base/java.lang.Thread.run(Thread.java:831)
Caused by: java.lang.IllegalAccessError: superclass access check failed: class com.sun.javafx.scene.control.ControlHelper (in unnamed module @0x9529d1f) cannot access class com.sun.javafx.scene.layout.RegionHelper (in module javafx.graphics) because module javafx.graphics does not export com.sun.javafx.scene.layout to unnamed module @0x9529d1f
    at java.base/java.lang.ClassLoader.defineClass1(Native Method)
    at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1010)
    at java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:150)
    at java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(BuiltinClassLoader.java:855)
    at java.base/jdk.internal.loader.BuiltinClassLoader.findClassOnClassPathOrNull(BuiltinClassLoader.java:753)
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:676)
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:634)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:182)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:519)
    at javafx.scene.control.Control.<clinit>(Control.java:86)
    at com.mathieuascain.javafxtutorial.Main.start(Main.java:22)
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$9(LauncherImpl.java:846)
    at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runAndWait$12(PlatformImpl.java:474)
    at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$10(PlatformImpl.java:447)
    at java.base/java.security.AccessController.doPrivileged(AccessController.java:391)
    at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$11(PlatformImpl.java:446)
    at javafx.graphics/com.sun.glass.ui.InvokeLaterDispatcher$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
Exception running application com.mathieuascain.javafxtutorial.Main

Process finished with exit code 1

Answer 1

You could try adding ALL JavaFX Components like: (replace version 15 with 16)

   <!-- JavaFx -->
            <dependency>
                <groupId>org.openjfx</groupId>
                <artifactId>javafx-base</artifactId>
                <version>15</version>
            </dependency>
    
            <dependency>
                <groupId>org.openjfx</groupId>
                <artifactId>javafx-controls</artifactId>
                <version>15</version>
            </dependency>
    
            <dependency>
                <groupId>org.openjfx</groupId>
                <artifactId>javafx-graphics </artifactId>
                <version>15</version>
                <classifier>win</classifier>
            </dependency>
    
            <dependency>
                <groupId>org.openjfx</groupId>
                <artifactId>javafx-fxml</artifactId>
                <version>15</version>
            </dependency>
    
            <dependency>
                <groupId>org.openjfx</groupId>
                <artifactId>javafx-web</artifactId>
                <version>15</version>
            </dependency>
    
            <dependency>
                <groupId>org.openjfx</groupId>
                <artifactId>javafx-media</artifactId>
                <version>15</version>
            </dependency>
    
             <dependency>
                <groupId>org.openjfx</groupId>
                <artifactId>javafx-swing</artifactId>
                <version>15</version>
            </dependency>