Why do I have java.lang.ClassNotFoundException while trying to run JavaFx application?

Question

I have tried to create example application as described here and the code is this:

package colorfulcircles;

import javafx.animation.KeyFrame;
import javafx.animation.KeyValue;
import javafx.animation.Timeline;
import javafx.application.Application;
import javafx.scene.Group;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.effect.BlendMode;
import javafx.scene.effect.BoxBlur;
import javafx.scene.paint.Color;
import javafx.scene.paint.CycleMethod;
import javafx.scene.paint.LinearGradient;
import javafx.scene.paint.Stop;
import javafx.scene.shape.Circle;
import javafx.scene.shape.Rectangle;
import javafx.scene.shape.StrokeType;
import javafx.stage.Stage;
import javafx.util.Duration;
import static java.lang.Math.random;


public class ColorfulCircles extends Application {

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

    @Override
    public void start(Stage primaryStage) {
        Group root = new Group();
        Scene scene = new Scene(root, 800, 600, Color.BLACK);
        primaryStage.setScene(scene);
        Group circles = new Group();
        for (int i = 0; i < 30; i++) {
            Circle circle = new Circle(150, Color.web("white", 0.05));
            circle.setStrokeType(StrokeType.OUTSIDE);
            circle.setStroke(Color.web("white", 0.16));
            circle.setStrokeWidth(4);
            circles.getChildren().add(circle);
        }
        Rectangle colors = new Rectangle(scene.getWidth(), scene.getHeight(),
                new LinearGradient(0f, 1f, 1f, 0f, true, CycleMethod.NO_CYCLE, new Stop[]{
                    new Stop(0, Color.web("#f8bd55")),
                    new Stop(0.14, Color.web("#c0fe56")),
                    new Stop(0.28, Color.web("#5dfbc1")),
                    new Stop(0.43, Color.web("#64c2f8")),
                    new Stop(0.57, Color.web("#be4af7")),
                    new Stop(0.71, Color.web("#ed5fc2")),
                    new Stop(0.85, Color.web("#ef504c")),
                    new Stop(1, Color.web("#f2660f")),}));
        Group blendModeGroup =
                new Group(new Group(new Rectangle(scene.getWidth(), scene.getHeight(),
                     Color.BLACK), circles), colors);
        colors.setBlendMode(BlendMode.OVERLAY);
        root.getChildren().add(blendModeGroup);      
        circles.setEffect(new BoxBlur(10, 10, 3));
        Timeline timeline = new Timeline();
        for (Node circle : circles.getChildren()) {
            timeline.getKeyFrames().addAll(
                    new KeyFrame(Duration.ZERO, // set start position at 0
                    new KeyValue(circle.translateXProperty(), random() * 800),
                    new KeyValue(circle.translateYProperty(), random() * 600)),
                    new KeyFrame(new Duration(40000), // set end position at 40s
                    new KeyValue(circle.translateXProperty(), random() * 800),
                    new KeyValue(circle.translateYProperty(), random() * 600)));
        }
        // play 40s of animation
        timeline.play();
        primaryStage.show();
    }
}

Why am I getting Exception? I use NetBeans 7.1 RC1 Here is the screenshot.

enter image description here

Output:

java.lang.ClassNotFoundException: javafxapplication4.JavaFXApplication4
    at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:264)
    at com.javafx.main.Main.getAppClass(Main.java:409)
    at com.javafx.main.Main.launchApp(Main.java:435)
    at com.javafx.main.Main.main(Main.java:537)

This one?

Can't even read the stacktrace. It might have been worth mentioning which class the code was erroring on... — Cody S
– Cody S, Commented Dec 15, 2011 at 0:34
@RCola, I downvoted because you've asked 52 questions and you're still including screenshots of stacktraces. — mre
– mre, Commented Dec 15, 2011 at 1:37

SplinterReality · Accepted Answer · 2011-12-15 00:33:34Z

4

Just a wild guess based on what I can see in this screen shot: You renamed the main class of your application and Netbeans is still looking for the old class name to run it?

Try right clicking your project, and looking at the "Main Class" under "Run" in the window that pops up.

Otherwise, please post the stack trace itself, not a screen shot of it.

answered Dec 15, 2011 at 0:33

SplinterReality

3,4101 gold badge25 silver badges45 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

J.Olufsen Over a year ago

Project Properties> Run > Application class : "javafxapplication4.JavaFXApplication4"

J.Olufsen Over a year ago

Your guess was correct. I renamed it but I had to do as well following: project Properties>Run>Application Class : here change for new class!

Collectives™ on Stack Overflow

Why do I have java.lang.ClassNotFoundException while trying to run JavaFx application?

1 Answer 1

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related