Error: Could not find or load main class application.Main Caused by: java.lang.NoClassDefFoundError: javafx/application/Application JDK 11

Question

I am stuck at a very basic problem. I have created a simple hello world program using JavaFX which works fine on JDK 1.8. But when I switch to JDK-11 it throws following exception:

Error: Could not find or load main class application.Main
Caused by: java.lang.NoClassDefFoundError: javafx/application/Application

Following is the code I wrote in eclipse.

package application;

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


public class Main extends Application {

    private Scene theScene;
    @Override
    public void start(Stage primaryStage) {
try {

            FXMLLoader loader = new FXMLLoader(getClass().getResource("MyScene.fxml"));
            Parent mainPane = loader.load();


            theScene = new Scene(mainPane);
            primaryStage.setScene(theScene);
            primaryStage.show();

        } catch(Exception e) {
            e.printStackTrace();
        }
    }

    public void setTheScene(Scene theScene) {
        this.theScene = theScene;
    }

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

Where and how are you running it (In eclipse/Intellij, as JAR, etc)? — Gnas, Nov 15 '18 at 12:21
Possible duplicate of [JavaFX packaging: NoClassDefFoundError](https://stackoverflow.com/questions/52761836/javafx-packaging-noclassdeffounderror) — The Head Rush, Nov 15 '18 at 12:26
Java 11 doest not support javafx thats why you are getting this error. — GauravRai1512, Nov 15 '18 at 12:31
@TheHeadRush I want that my app should be able to run on both. java 8 and Java 11. Well I found on internet and it says that JavaFX is not the port of JDK11. Should I need to modify the app by adding external JavaFX libraries and recompile it? — Shahrukh S., Nov 15 '18 at 12:34
Java 11 doesn't _include_ JavaFX 11, but that doesn't mean it doesn't support it. You can run JavaFX 11 apps, and there is a getting started guide [here](https://openjfx.io/openjfx-docs/). — José Pereda, Nov 15 '18 at 12:35
@Gnas I build it using Eclipse: Exporting as Runable Jar file — Shahrukh S., Nov 15 '18 at 12:35
Are you building it with JDK 1.8 and running on JDK 11? Because that won't work due to the removal of JavaFX since JDK 11. From JDK 11 onwards you need to explicitly include JavaFX dependencies as you would any other third party libraries. — Gnas, Nov 15 '18 at 12:39
Thanks @Gnas. I included explicitly all java dependencies and I think it should now work. It is showing following error: Error: JavaFX runtime components are missing, and are required to run this application I think there is a very minor thing that I am missing my be there is something I have to add in environment variable. Actually I am new to Java that's why asking this stupid question. Could you please help me? — Shahrukh S., Nov 15 '18 at 13:49
@ShahrukhS. Did you follow the guide provided by José Pereda? — Gnas, Nov 15 '18 at 13:55

score 10 · Answer 1 · edited Sep 15 '19 at 22:22

I faced the same issue on debian after upgrading from stretch to buster, but now, everything is fine:

java --version

openjdk 11.0.4 2019-07-16

To run a java-fx application using terminal, follow these steps:

Install openjfx (if it is not already installed):
sudo apt install openjfx
List the javafx library location:
dpkg-query -L openjfx
The output should be like this:

. /usr /usr/share /usr/share/doc /usr/share/doc/openjfx /usr/share/doc/openjfx/TODO.Debian /usr/share/doc/openjfx/changelog.Debian.gz /usr/share/doc/openjfx/copyright /usr/share/openjfx /usr/share/openjfx/lib /usr/share/openjfx/lib/javafx.properties /usr/share/openjfx/lib/javafx.base.jar /usr/share/openjfx/lib/javafx.controls.jar /usr/share/openjfx/lib/javafx.fxml.jar /usr/share/openjfx/lib/javafx.graphics.jar /usr/share/openjfx/lib/javafx.media.jar /usr/share/openjfx/lib/javafx.swing.jar /usr/share/openjfx/lib/javafx.web.jar

Run the jar application by including the javafx path and modules:
java --module-path $PATH_TO_OPENJFX-LIB --add-modules module_1,module_2,module_3,...,module_n -jar $PATH_TO_JAR_FILE

Example:

java --module-path /usr/share/openjfx/lib --add-modules=javafx.controls,javafx.fxml,javafx.base,javafx.media,javafx.web,javafx.swing -jar '/home/lotfi/Documents/MyAppfolder/my_application.jar'

score 2 · Answer 2 · answered Feb 04 '19 at 13:37

2

jdk 11 does not have javafx support. Oracle removed it. But you can add javafx to your project using Maven.

answered Feb 04 '19 at 13:37

Alexandr Tkach

21
2

Yes, OpenFX recommends building it with your application (in the application jar) since Java 9. – Boyd Stephen Smith Jr. Sep 19 '19 at 20:49

clau · Answer 3 · 2020-08-21T13:27:59.367

1

I had a similar error when executing a java application, I could not find some packages already installed, I located the path where the application was reading and there I added a symbolic link to the javafx library that I had installed.

Example:

user@server:/usr/lib/jvm/java-8-openjdk-amd64/jre/lib$ sudo ln -s /usr/share/openjfx/lib/javafx.properties

edited Aug 21 '20 at 13:27

answered Aug 19 '20 at 21:52

clau

11
2

score 0 · Answer 4 · edited May 10 '20 at 10:30

0

In Eclipse : run configurations -> arguments -> VM arguments :

--module-path ${project_classpath:REPLACE_ME_WITH_YOUR_PROJECT_NAME} 

--add-modules javafx.controls,javafx.fxml

edited May 10 '20 at 10:30

David Buck

3,752
35
31
35

answered May 10 '20 at 10:15

Nguyễn Tùng Lâm

1

Error: Could not find or load main class application.Main Caused by: java.lang.NoClassDefFoundError: javafx/application/Application JDK 11

4 Answers4

Example:

Linked