javafx.fxml.LoadException when ran from a compiled jar

Question

When ran locally from within IntelliJ my JavaFX application starts fine, but when it is compiled into a jar and then made accessible to users in the client I receive the following exception. Any idea as to why this could be?

(07:56:06) javafx.fxml.LoadException:
unknown path:10

(07:56:06)      at javafx.fxml.FXMLLoader.constructLoadException(Unknown Source)

(07:56:06)      at javafx.fxml.FXMLLoader.access$700(Unknown Source)
(07:56:06)      at javafx.fxml.FXMLLoader$ValueElement.processAttribute(Unknown
Source)
(07:56:06)      at javafx.fxml.FXMLLoader$InstanceDeclarationElement.processAttr
ibute(Unknown Source)
(07:56:06)      at javafx.fxml.FXMLLoader$Element.processStartElement(Unknown So
urce)
(07:56:06)      at javafx.fxml.FXMLLoader$ValueElement.processStartElement(Unkno
wn Source)
(07:56:06)      at javafx.fxml.FXMLLoader.processStartElement(Unknown Source)
(07:56:06)      at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
(07:56:06)      at javafx.fxml.FXMLLoader.load(Unknown Source)
(07:56:06)      at scripts.MassFighter.GUI.Main.start(Main.java:22)
(07:56:06)      at scripts.MassFighter.MassFighter.lambda$showAndWaitGUI$0(MassF
ighter.java:114)
(07:56:06)      at scripts.MassFighter.MassFighter$$Lambda$351/222230364.run(Unk
nown Source)
(07:56:06)      at com.sun.javafx.application.PlatformImpl.lambda$null$164(Unkno
wn Source)
(07:56:06)      at com.sun.javafx.application.PlatformImpl$$Lambda$53/1296636313
.run(Unknown Source)
(07:56:06)      at java.security.AccessController.doPrivileged(Native Method)
(07:56:06)      at com.sun.javafx.application.PlatformImpl.lambda$runLater$165(U
nknown Source)
(07:56:06)      at com.sun.javafx.application.PlatformImpl$$Lambda$52/47061671.r
un(Unknown Source)
(07:56:06)      at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(Unknown Sou
rce)
(07:56:06)      at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
(07:56:06)      at com.sun.glass.ui.win.WinApplication.lambda$null$141(Unknown S
ource)
(07:56:06)      at com.sun.glass.ui.win.WinApplication$$Lambda$43/157734934.run(
Unknown Source)
(07:56:06)      at java.lang.Thread.run(Unknown Source)
(07:56:06) Caused by: java.lang.ClassNotFoundException: scripts.MassFighter.GUI.
Controller
(07:56:06)      at java.net.URLClassLoader$1.run(Unknown Source)
(07:56:06)      at java.net.URLClassLoader$1.run(Unknown Source)
(07:56:06)      at java.security.AccessController.doPrivileged(Native Method)
(07:56:06)      at java.net.URLClassLoader.findClass(Unknown Source)
(07:56:06)      at java.lang.ClassLoader.loadClass(Unknown Source)
(07:56:06)      at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
(07:56:06)      at java.lang.ClassLoader.loadClass(Unknown Source)
(07:56:06)      ... 20 more

I have included the FXML file as a resource in the manifest:

<resource>scripts/resources/FighterDesign.fxml</resource>

Here is the code I use to find the resource and launch the application (Main.java):

private Controller controller;

    @Override
    public void start(Stage primaryStage) throws Exception {
        InputStream in = MassFighter.class.getResourceAsStream("/scripts/MassFighter/GUI/FighterV1.fxml");
        if (in != null) {
            FXMLLoader loader = new FXMLLoader();
            Parent root = loader.load(in);
            primaryStage.setTitle("MassFighter V4");
            primaryStage.setScene(new Scene(root));
            controller = loader.getController();
            controller.initialize();
            primaryStage.setOnCloseRequest(event -> {
                System.out.println("UI Closed - Stopping Script");
                if (Environment.getScript().isRunning()) {
                    Environment.getScript().stop();
                }
                close();
            });
            primaryStage.show();
        } else {
            MassFighter.status = "Input Stream Unavailable"; // the input stream is not null when this error occurs
        }
    }

Here is where I link the FXML file to my controller:

<Pane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" opacity="0.89" prefHeight="431.0" prefWidth="672.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="scripts.MassFighter.GUI.Controller">

Here is the code I use to invoke the start method:

ui = new Main();
    Platform.runLater(() -> {
        try {
            ui.start(new Stage());
        } catch (Exception e) {
            e.printStackTrace();
        }
    });
    while (setupRunning) {
        Execution.delay(100);
    }
    Platform.runLater(ui::close);

This is my project structure:

Any help is appreciated as I'm really puzzled! Thanks in advance.

Answer 1

I had a similar problem loading a resource file from a JAR built on Windows and when it ran in Linux, see the solution for the following question ...

• What is correct URL to specify ResourceBase of JAR “resources/..."

In your case you'll need to put in the applicable file/path names. Remember that the FMXL directory (if that's what you use) is going to be:

String fileName = "/fxml/this-under-resources.fxml";

Which in your project is under:

src/main/resources/
  fxml/
    this-under-resources.fxml

That syntax works OK but, if you don't know where your execution path is; you need to get the FXML source path equivalent for my HTML example, something very similar to:

jar:/fxml/this-under-resources.fxml

More or less. and then use code similar to the Jetty/HTML case, viz.

 URL     baseUrl  = SplitFileServerRunner.class.getResource( baseStr ); 
String  basePath = baseUrl.toExternalForm();

And so on.

Since that question, I've moved-on. I only wish to keep any presentation resources in the JAR for use a "fall-back" and as default views (or other resources).

The thing to recall about "external path" is that it is a run-time thing so every/anytime your run your JAR file; the answer ought to be correct. As long as you have suitable permissions and access rights. Good luck.