InvocationTargetException when running a javafx pr

问题:

So this worked in the example from javafx when My pc had jdk 1.7.0 so this may be the new version of FX in java8 however;

I get a nice stack-trace

jfx-project-run:
Executing E:\workspace\PathFinderApp\dist\run1095471771\PathFinderApp.jar using platform C:\Program Files\Java\jdk1.8.0\jre/bin/java
Exception in Application start method
java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:367)
    at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:305)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:767)
Caused by: java.lang.RuntimeException: Exception in Application start method
    at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:894)
    at com.sun.javafx.application.LauncherImpl.access$000(LauncherImpl.java:56)
    at com.sun.javafx.application.LauncherImpl$1.run(LauncherImpl.java:158)
    at java.lang.Thread.run(Thread.java:744)
Caused by: javafx.fxml.LoadException: 
file:/E:/workspace/PathFinderApp/dist/run1095471771/PathFinderApp.jar!/com/rpg/gui/main.fxml:11

    at javafx.fxml.FXMLLoader.constructLoadException(FXMLLoader.java:2617)
    at javafx.fxml.FXMLLoader.access$700(FXMLLoader.java:104)
    at javafx.fxml.FXMLLoader$ValueElement.processAttribute(FXMLLoader.java:937)
    at javafx.fxml.FXMLLoader$InstanceDeclarationElement.processAttribute(FXMLLoader.java:976)
    at javafx.fxml.FXMLLoader$Element.processStartElement(FXMLLoader.java:216)
    at javafx.fxml.FXMLLoader$ValueElement.processStartElement(FXMLLoader.java:738)
    at javafx.fxml.FXMLLoader.processStartElement(FXMLLoader.java:2723)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2527)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2441)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3230)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3191)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3164)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3140)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3120)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:3113)
    at com.rpg.gui.GUI.loadMainPane(GUI.java:34)
    at com.rpg.gui.GUI.initialize(GUI.java:20)
    at Main.start(Main.java:20)
    at com.sun.javafx.application.LauncherImpl$8.run(LauncherImpl.java:837)
    at com.sun.javafx.application.PlatformImpl$7.run(PlatformImpl.java:335)
    at com.sun.javafx.application.PlatformImpl$6$1.run(PlatformImpl.java:301)
    at com.sun.javafx.application.PlatformImpl$6$1.run(PlatformImpl.java:298)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl$6.run(PlatformImpl.java:298)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.access$300(WinApplication.java:39)
    at com.sun.glass.ui.win.WinApplication$4$1.run(WinApplication.java:112)
    ... 1 more
Caused by: java.lang.InstantiationException: com.rpg.gui.MainController
    at java.lang.Class.newInstance(Class.java:418)
    at sun.reflect.misc.ReflectUtil.newInstance(ReflectUtil.java:51)
    at javafx.fxml.FXMLLoader$ValueElement.processAttribute(FXMLLoader.java:932)
    ... 26 more
Caused by: java.lang.NoSuchMethodException: com.rpg.gui.MainController.<init>()
    at java.lang.Class.getConstructor0(Class.java:2971)
    at java.lang.Class.newInstance(Class.java:403)
    ... 28 more
Exception running application Main
Java Result: 1

basically telling me something is wrong here "com/rpg/gui/main.fxml:11"

and that line is

<AnchorPane id="AnchorPane" prefHeight="400.0" prefWidth="600.0" xmlns:fx="http://javafx.com/fxml" fx:controller="com.rpg.gui.MainController">

so I can figure out that it doesn't like something to do with the main controller, so it has to be somthing to do with loading the fxml and the controller right? but thats about where my ideas end

MainController mainController = new MainController(path);
Pane mainPane = FXMLLoader.load(getClass().getResource("main.fxml"));
Window.setMainController(mainController);
Window.swap(path+"content.fxml");

that's the method it throws everything in anyone experienced in javaFX or know of any changes in java8 that'd do this??

回答1:

Your MainController doesn't have a zero-argument constructor. If the FXMLLoader encounters a fx:controller attribute on the root element, it attempts to create an instance of that controller by (effectively) calling the zero-argument constructor of the class specified in the attribute.

To fix this (the simplest way), remove the fx:controller attribute from the FXML file, and set the controller "by hand" on the FXMLLoader. You need to create an FXMLLoader instance instead of relying on the static load(...) method:

FXMLLoader loader = new FXMLLoader(getClass().getResource("main.fxml"));
loader.setController(new MainController(path));
Pane mainPane = loader.load();

回答2:

I faced the same problem and want to share a little bit related to it. I'm using java 8 and Netbeans 8.1 and when I created a javafx FXML Application I got this one.
Here are some tips:

1. When you create new project clean and build your project before you try to run.
2. If you rename any file (controller, fxml) IDE do not apply changes to other files at least Netbeans is not doing so. So, you have to change those file names in other files manually.

3. You can define controller either in fxml file or in main class. If you want to define controller in main class use the method described by @James_D. If you want to define in fxml file than use fx:controller attribute as

    fx:controller="yourProjectName.yourFXMLDocumentControllerName"
   

   and in main class reference it as

   Parent root = FXMLLoader.load(getClass().getResource("yourFXMLFileName.fxml"));
   

4. If you think everything is correct but you still getting the error clean and build your project again and try to run.

Hope it would help someone.

回答3:

I also encounter that a lot... There seems to be a bug in Scenebuilder/netbeans 8, where upon saving in Scenebuilder, it creates another xmlns:fx="..." so that may be an issue...

Also, looking at fxml's i have using java8, I have these: xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1"

where I noticed your's is: xmlns:fx="http://javafx.com/fxml"

回答4:

You used

Pane mainPane = FXMLLoader.load(getClass().getResource("main.fxml"));

Try

Pane mainPane = FXMLLoader.load(getClass().getResource("/main.fxml"));

回答5:

If Any One does not fix the problem by following answers, The simple way is to create new fxml Empty class then click on edit of the fxml causin the problem and copy the xml code to the new class . Go to the start() methode, change the:

Pane mainPane = FXMLLoader.load(getClass().getResource("main.fxml"));

to

Pane mainPane = FXMLLoader.load(getClass().getResource("newClass.fxml"));

回答6:

For anyone struggling with JDK11 / JavaFX11

The reason I was getting this error is because the project was dependent on a UI module which contained the FXML references and thus graphics configuration. I noticed these lines in the compile log dump below:

Caused by: java.lang.IllegalAccessException: class com.sun.javafx.application.LauncherImpl (in module javafx.graphics) cannot access class academy.learnprogramming.ui.Main (in module academy.learnprogramming.common) because module academy.learnprogramming.common does not export academy.learnprogramming.ui to module javafx.graphics

So

Assuming this is NOT a maven project, Project/module-name/src/module-info.java you needed to make sure the module system had access to all your modules in the project:

module com.test.common {

    requires javafx.fxml;
    requires javafx.controls;
    requires javafx.graphics;
    requires java.sql;
    // ... etc.



    opens com.test.common;
    opens com.test.ui;        // For my particular case, I had Forgotten this one
    opens com.test.db;        // And this one
}

FOR REFERENCE:

Exception in Application constructor
Exception in thread "main" java.lang.reflect.InvocationTargetException
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:566)
    at java.base/sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:1051)
Caused by: java.lang.RuntimeException: Unable to construct Application instance: class academy.learnprogramming.ui.Main
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:890)
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication$2(LauncherImpl.java:195)
    at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: java.lang.IllegalAccessException: class com.sun.javafx.application.LauncherImpl (in module javafx.graphics) cannot access class academy.learnprogramming.ui.Main (in module academy.learnprogramming.common) because module academy.learnprogramming.common does not export academy.learnprogramming.ui to module javafx.graphics
    at java.base/jdk.internal.reflect.Reflection.newIllegalAccessException(Reflection.java:361)
    at java.base/java.lang.reflect.AccessibleObject.checkAccess(AccessibleObject.java:591)
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481)
    at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$8(LauncherImpl.java:802)
    at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runAndWait$12(PlatformImpl.java:455)
    at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$10(PlatformImpl.java:428)
    at java.base/java.security.AccessController.doPrivileged(Native Method)
    at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$11(PlatformImpl.java:427)
    at javafx.graphics/com.sun.glass.ui.InvokeLaterDispatcher$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