IntelliJ JavaFX problem with JFoenix when adding a component: Exception in Application start method java.lang.reflect.InvocationTargetException

Question

I stumbled upon this problem. When I use a JFoenix component in the JavaFX sample project, it returns an error. All I did was simply insert the JFXButton in the SceneBuilder to test what this material library would look like. I did not change anything except add the JFXButton in the scene builder then the sample project wouldn't work anymore. What seems to be the problem here?

Project Files

hello-view in SceneBuilder

HelloApplication.Java

package com.cjc.aidre.csjavafx;

import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Scene;
import javafx.stage.Stage;

import java.io.IOException;

public class HelloApplication extends Application {
    @Override
    public void start(Stage stage) throws IOException {
        FXMLLoader fxmlLoader = new FXMLLoader(HelloApplication.class.getResource("hello-view.fxml"));
        Scene scene = new Scene(fxmlLoader.load(), 320, 240);
        stage.setTitle("Hello!");
        stage.setScene(scene);
        stage.show();
    }

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

HelloController.java

package com.cjc.aidre.csjavafx;

public class HelloController {
}

**hello-view.fxml

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

<?import com.jfoenix.controls.JFXButton?>
<?import javafx.geometry.Insets?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.layout.VBox?>

<VBox alignment="CENTER" prefHeight="51.0" prefWidth="92.0" spacing="20.0" xmlns="http://javafx.com/javafx/8.0.171" xmlns:fx="http://javafx.com/fxml/1" fx:controller="com.cjc.aidre.csjavafx.HelloController">
    <padding>
        <Insets bottom="20.0" left="20.0" right="20.0" top="20.0" />
    </padding>
   <JFXButton textAlignment="CENTER" />

    <Label fx:id="welcomeText" />
</VBox>

"C:\Program Files\Eclipse Adoptium\jdk-17.0.2.8-hotspot\bin\java.exe" "-javaagent:G:\IntelliJ IDEA Community Edition 2021.3.1\lib\idea_rt.jar=59021:G:\IntelliJ IDEA Community Edition 2021.3.1\bin" -Dfile.encoding=UTF-8 -classpath C:\Users\alscg\.m2\repository\org\openjfx\javafx-controls\17.0.1\javafx-controls-17.0.1.jar;C:\Users\alscg\.m2\repository\org\openjfx\javafx-graphics\17.0.1\javafx-graphics-17.0.1.jar;C:\Users\alscg\.m2\repository\org\openjfx\javafx-base\17.0.1\javafx-base-17.0.1.jar;C:\Users\alscg\.m2\repository\org\openjfx\javafx-fxml\17.0.1\javafx-fxml-17.0.1.jar;G:\javafx-sdk-17.0.2\lib\javafx-swt.jar;G:\javafx-sdk-17.0.2\lib\javafx.web.jar;G:\javafx-sdk-17.0.2\lib\javafx.media.jar;G:\javafx-sdk-17.0.2\lib\javafx.swing.jar;G:\Java\jfoenix-8.0.10.jar -p C:\Users\alscg\.m2\repository\org\openjfx\javafx-controls\17.0.1\javafx-controls-17.0.1-win.jar;G:\javafx-sdk-17.0.2\lib\javafx.controls.jar;C:\Users\alscg\.m2\repository\org\openjfx\javafx-graphics\17.0.1\javafx-graphics-17.0.1-win.jar;G:\javafx-sdk-17.0.2\lib\javafx.graphics.jar;C:\Users\alscg\.m2\repository\org\openjfx\javafx-fxml\17.0.1\javafx-fxml-17.0.1-win.jar;G:\javafx-sdk-17.0.2\lib\javafx.fxml.jar;C:\Users\alscg\.m2\repository\org\openjfx\javafx-base\17.0.1\javafx-base-17.0.1-win.jar;G:\javafx-sdk-17.0.2\lib\javafx.base.jar;C:\Users\alscg\IdeaProjects\CSJavaFX\target\classes -m com.cjc.aidre.csjavafx/com.cjc.aidre.csjavafx.HelloApplication
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:77)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:568)
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:465)
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:364)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:568)
    at java.base/sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:1071)
Caused by: java.lang.RuntimeException: Exception in Application start method
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:901)
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication$2(LauncherImpl.java:196)
    at java.base/java.lang.Thread.run(Thread.java:833)
Caused by: javafx.fxml.LoadException: 
/C:/Users/alscg/IdeaProjects/CSJavaFX/target/classes/com/cjc/aidre/csjavafx/hello-view.fxml:12

    at javafx.fxml/javafx.fxml.FXMLLoader.constructLoadException(FXMLLoader.java:2707)
    at javafx.fxml/javafx.fxml.FXMLLoader$InstanceDeclarationElement.constructValue(FXMLLoader.java:1022)
    at javafx.fxml/javafx.fxml.FXMLLoader$ValueElement.processStartElement(FXMLLoader.java:757)
    at javafx.fxml/javafx.fxml.FXMLLoader.processStartElement(FXMLLoader.java:2808)
    at javafx.fxml/javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2634)
    at javafx.fxml/javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2548)
    at javafx.fxml/javafx.fxml.FXMLLoader.load(FXMLLoader.java:2516)
    at com.cjc.aidre.csjavafx/com.cjc.aidre.csjavafx.HelloApplication.start(HelloApplication.java:14)
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$9(LauncherImpl.java:847)
    at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runAndWait$12(PlatformImpl.java:484)
    at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$10(PlatformImpl.java:457)
    at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
    at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$11(PlatformImpl.java:456)
    at javafx.graphics/com.sun.glass.ui.InvokeLaterDispatcher$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$3(WinApplication.java:184)
    ... 1 more
Caused by: java.lang.reflect.InvocationTargetException
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:77)
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
    at javafx.fxml/javafx.fxml.FXMLLoader$InstanceDeclarationElement.constructValue(FXMLLoader.java:1020)
    ... 15 more
Caused by: java.lang.NoClassDefFoundError: com/sun/javafx/css/StyleConverterImpl
    at java.base/java.lang.ClassLoader.defineClass1(Native Method)
    at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1012)
    at java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:150)
    at java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(BuiltinClassLoader.java:862)
    at java.base/jdk.internal.loader.BuiltinClassLoader.findClassOnClassPathOrNull(BuiltinClassLoader.java:760)
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:681)
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:639)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
    at com.jfoenix.controls.JFXButton$StyleableProperties.<clinit>(JFXButton.java:207)
    at com.jfoenix.controls.JFXButton.<init>(JFXButton.java:155)
    ... 21 more
Caused by: java.lang.ClassNotFoundException: com.sun.javafx.css.StyleConverterImpl
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
    ... 32 more
Exception running application com.cjc.aidre.csjavafx.HelloApplication

Process finished with exit code 1

Answer 1

Your project setup seems to be broken. You are mixing artefacts from .m2 maven repository with an explicit SDK reference. See 17.0.2 vs 17.0.1.

In addition to the incorrect mixed Java version. You are using the wrong version of jfoenix.

Read the jfoenix documentation

Java 9+ needs a 9.x version of the library, not an 8.x version.

<dependency>
    <groupId>com.jfoenix</groupId>
    <artifactId>jfoenix</artifactId>
    <version>9.0.10</version>
</dependency>

Also, the jfoenix library may currently have issues with recent JavaFX versions, see:

• Working with JavaFX in Maven (Jfoenix 9.0.10 dependency issue)