Exception in application start method javafx ошибка

The exception in application start method java.lang.reflect.InvocationTargetException is an error code that occurs when you are using JavaFX. There are myriad situations that cause this error. Keep on reading, as we’ll give you detailed explanations of these causes and their fix.

By the end of this article, you’ll know how to prevent and fix the error in your future JavaFX projects.

You have an exception in java.lang.reflect.InvocationTargetException because of the following:

• You have a starting forward slash in the pathname of your FXML file
• You are missing JavaFX modules
• You are using dynamic root without setting the root on the FXMLLoader

– Having a Starting Forward Slash in the Pathname of Your Fxml File

A forward slash in the pathname of your FXML file can cause an exception in JavaFX. For example, the following code can trigger the exception:

FXMLLoader loader = new FXMLLoader(Main.class.getResource(“/File.fxml”));

When you check the previous code, you’ll note that we have a forward slash before the FXML file. Though this will work on some systems, but on most systems, it’ll cause an exception.

– Missing Javafx Modules

Missing JavaFX modules when running JavaFX can cause an exception. The “Getting Started with JavaFX” on OpenJFX outlined steps for a JavaFX project with IntelliJ IDEA. Check the below points:

• Create a JavaFX project
  • At this stage, you give your project a name
  • Give the project a location
• Set JDK 17
  • You do this by navigating to File → Project Structure → Project
  • Also, you can set the language level to a minimum value of 11
• Create a library
  • Navigate to File → Project Structure → Libraries
  • Add JavaFX 17 SDK as a library
  • Point to the lib folder of the SDK
    • Once you apply the library, IntelliJ will recognize the JavaFX classes

If you perform all the operations outlined in the previous steps, your code will compile but you’ll get an error. That’s because IntelliJ does not include some modules that’ll make your code work. For the code to work, you have to tell Java which modules it’ll use for your application.

Keep on reading, as we’ll explain how you can fix this in the “How To Fix” section.

– Using Dynamic Root Without Setting the Root on the Fxmlloader

You’ll raise an exception if you use the dynamic root <fx:root type=”AnchorPane”> without setting the root on the FXMLLoader. That’s because < fx:root> specifies a dynamic root for your FXML file. So, its root is an object that you must set before loading the FXML file. Meanwhile, a use case for this is when you want to define the layout of custom controls with FXML.

For example, an exception occurs in the following public class. This class extends the Application class in JavaFX:

public class HelloWorld extends Application {
@Override
public void start(Stage stage) throws Exception {
Parent root = FXMLLoader.load(getClass().getResource(“MyFXMLDoc.fxml”));
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
}

In the above-mentioned code, we’ve called the load() method of FXMLLoader on the FXML file but we did not set any root before trying to load the FXML file. As a result, the code causes an exception.

How To Fix the Exception in Application Error?

You can fix the exception by updating your code or adding the required JavaFX modules. As a result, your code will work as expected. However, it’s easier said than done. In this section, we’ll go into detail on how to fix and prevent the exception in your project.

– Remove the Forward Slash in the Path Name of the Fxml File

When you load your FXML file with FXMLLoader, observe if there is a forward slash in the pathname of the FXML file. If you are getting an exception, remove this forward slash. Afterward, your code should work. For example, the following is a code we showed you earlier:

FXMLLoader loader = new FXMLLoader(Main.class.getResource(“/File.fxml”));

From the code, we have the forward slash before File.fxml but in the code below, we’ve eliminated the forward slash. So, your code should work.

There are cases where the absence of the forward slash caused an exception. So, if you are in such a situation, add the forward slash to prevent the exception.

– Update Intellij Idea To Use Javafx Modules Via the vm Options

In IntelliJ IDEA, you’ll need to add the JavaFX modules as a VM option based on your Operating System. We say “JavaFX modules” because JavaFX is a collection of modules. We base this solution on the “Getting Started” tutorial on OpenJFX. Earlier, we mentioned that if you compile your code without the JavaFX modules, you’ll get an error.

To add the VM options, go to the following location in IntelliJ IDEA:

Run → Edit Configurations

At the above location, if you are on Windows, add the VM options using the following:

–module-path “pathtojavafx-sdk-17.0.1lib” –add-modules javafx.controls,javafx.fxml

If you are on Linux or Mac, use the following:

–module-path /path/to/javafx-sdk-17.0.1/lib –add-modules javafx.controls,javafx.fxml

As an alternative, you can define a global variable for future projects. To get started, navigate the following path in IntelliJ:

1. Preferences (File → Settings) → Appearance & Behavior → Path Variables
2. Define the variable name as PATH_TO_FX
3. Browse to the lib folder of the JavaFX SDK to set its value
4. Click apply

Afterward, you can refer to this global variable when you set the VM options:

–module-path ${PATH_TO_FX} –add-modules javafx.controls,javafx.fxml

Once you’ve added the VM options, run your project, and your code should work fine.

The project created on the OpenJFX tutorial is the default project that uses FXML therefore, your code requires javafx.fxml and javafx.controls. Note that if your project uses other modules, you should add them. So, after adding the modules, save your settings.

– Set the Root on Fxmlloader Before Loading the Fxml File

To prevent the exception, you should set the root on FXMLLoader before you load your FXML file. The next code block is a sample class that we discussed earlier. In the code, we did not set the root before loading the FXML file. As a result, we get an error.

public class HelloWorld extends Application {
@Override
public void start(Stage stage) throws Exception {
Parent root = FXMLLoader.load(getClass().getResource(“MyFXMLDoc.fxml”)); // Where the error occurred
Scene scene = new Scene(root);
stage.setScene(scene); stage.show();
}
}

However, in our next code, we’ve made corrections. The corrections ensure the proper use of <fx:root> which are the following:

• Create an FXMLLoader instance
• Call setRoot() on the instance
  • Pass in the root object of the FXML

public class HelloWorld extends Application {
@Override
public void start(Stage stage) throws Exception {
// Create an FXMLLoader Instance
FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource(“MyFXMLDoc.fxml”));
// Call setRoot on the instance
fxmlLoader.setRoot(new AnchorPane());
// Call the load() function on the file
Parent root = fxmlLoader.load();
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
}

Conclusion

This article explained how to fix the causes of the exception when you are using JavaFX. We provided coding examples and explained solutions with actionable steps to identify and solve the issue. Here are the summary of the most important points that we talked in the article:

• A starting forward slash in the path name of an FXML file can cause an exception.
• Not setting the root before loading the XML file leads to an exception.
• To prevent an exception when working with JavaFX in IntelliJ, use JavaFX modules.
• You can add JavaFX modules as VM options in IntelliJ IDEA.
• You can prevent the failure from happening by setting the root on FXMLLoader before you load your FXML file.

At this stage, you have what it takes to fix the exception in your application and run an error-free code.

JavaFX is a highly enriched library whose code gets written in native Java code. The library gets used to making Rich Internet Applications, often known as RIA.

The library is a set of interfaces and classes that are easily understandable and are a friendly alternative to Java Virtual Machine or JVM. The code written using the library can run across multiple platforms without fail like desktops, mobiles, televisions, etc.

Long back, the graphical User Interface gets built using Swing templates, but after the advent of JavaFX, one can easily rely on the language to work over the same. The applications built using JavaFx have a penetration rate of 76 percent.

The Exception in Application start method is the runtime error that occurs when the application is running and when compilation gets done. The state occurs when the application is inefficient in loading runtime variables or files. It can throw NullPointerException, FileNotFound type of exceptions when not handled properly.

Additionally, plugins like SonarLint, programming mistake detector(PMD), find bugs can help identify the runtime issues beforehand without actual program runs.

Below is an example to show the Exception in Application start method error in JavaFx.

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

public class ApplicationStart extends Application {
    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage stage) throws Exception {
        Parent parent = FXMLLoader.load(getClass().getResource("AnyXML.fxml"));
        Scene scene = new Scene(parent);
        stage.setScene(scene);
        stage.setTitle("First Swing Sample");
        stage.show();
    }
}

The above source code that seems to be in JavaFx has a main method in the ApplicationStart class. The given class extends an abstract Application class and is specifically available in JavaFX Library.

It has a default theme called Caspein that gets launched once you start the application. The launch is a static method present in the Application class and gets called from the main function. It takes variable arguments or varargs as its parameters. It throws IllegalStateException if the launch method gets called more than once.

The Application class has one abstract method whose implementation must be present in ApplicationStart class. The override annotation shows that the code below the annotation belongs to the parent Application class. The implementation of the method that gets proceeded by the annotation override is present below the annotation.

The start method is the main entry for the JavaFX applications, as main is the entry location for the Java applications. The main method gets first called when the Application or main thread gets initialized.

The function takes Stage as the parameter. The Stages denotes the primary step or view and gets loaded when the application launches in the applet viewer. It also throws Exception that gets defined along with the method.

The first statement inside the method is to load the XML file. The FXMLLoader class loads an object hierarchy from the XML object model. It gets used to bring the object hierarchy from an FXML document into a Parent instance. It takes the parameter as the URL to the location where the XML document hierarchy is present.

The resultant gets stored in a Parent class instance that holds the subtypes in the graph format. The Scene class present in the JavaFX library is the container unit that stores all the data in a graph view. The background of the scene gets filled by the specified property. The instance of Stage class gets created and can get used with other properties.

Below mentioned are the properties used to display the scene over the browser.

• The setScene method makes its use to specify the scene and gets used along with the stage instance variable.
• The setTitle function gets used to set scene title present over the browser. The show function gets used to populate the scene over the stage.

Below is the output for the above code block.

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:498)
	at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:389)
	at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:328)
	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:498)
	at sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:873)
Caused by: java.lang.RuntimeException: Exception in Application start method
	at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:917)
	at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$1(LauncherImpl.java:182)
	at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.NullPointerException: Location is required.
	at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3207)
	at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3175)
	at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3148)
	at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3124)
	at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3104)
	at javafx.fxml.FXMLLoader.load(FXMLLoader.java:3097)
	at ApplicationStart.start(ApplicationStart.java:15)
	at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$8(LauncherImpl.java:863)
	at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$7(PlatformImpl.java:326)
	at com.sun.javafx.application.PlatformImpl.lambda$null$5(PlatformImpl.java:295)
	at java.security.AccessController.doPrivileged(Native Method)
	at com.sun.javafx.application.PlatformImpl.lambda$runLater$6(PlatformImpl.java:294)
	at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
	at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
	at com.sun.glass.ui.win.WinApplication.lambda$null$3(WinApplication.java:177)
	... 1 more
Exception running application ApplicationStart

In the output shown above, the issue gets raised at the parameter position that uses the FXMLLoader class to load the XML object, but it returns a null value. In simple words, the getResource() method does not locate the path provided in the function parameter.

Hence, the null value populates NullPointerException, which is a type of runtime exception. And are handled by giving an absolute path where the file can get located. The stack trace often shows the line number where the issue starts populating. The target must be correct when get given in the load parameter.

Hence the given solution to the problem is below.

1. Give the absolute path to the location where the file gets present.
2. Add a SonarLint plugin to the Integrated Development Environment that helps in evaluating or handling the exceptions at the write time.

Fix JavaFx Exception in Application Start Method

JavaFX is a highly enriched library whose code gets written in native Java code. The library gets used to making Rich Internet Applications, often known as RIA.

The library is a set of interfaces and classes that are easily understandable and are a friendly alternative to Java Virtual Machine or JVM. The code written using the library can run across multiple platforms without fail like desktops, mobiles, televisions, etc.

Long back, the graphical User Interface gets built using Swing templates, but after the advent of JavaFX, one can easily rely on the language to work over the same. The applications built using JavaFx have a penetration rate of 76 percent.

The Exception in Application start method is the runtime error that occurs when the application is running and when compilation gets done. The state occurs when the application is inefficient in loading runtime variables or files. It can throw NullPointerException, FileNotFound type of exceptions when not handled properly.

Additionally, plugins like SonarLint, programming mistake detector(PMD), find bugs can help identify the runtime issues beforehand without actual program runs.

Below is an example to show the Exception in Application start method error in JavaFx.

The above source code that seems to be in JavaFx has a main method in the ApplicationStart class. The given class extends an abstract Application class and is specifically available in JavaFX Library.

It has a default theme called Caspein that gets launched once you start the application. The launch is a static method present in the Application class and gets called from the main function. It takes variable arguments or varargs as its parameters. It throws IllegalStateException if the launch method gets called more than once.

The Application class has one abstract method whose implementation must be present in ApplicationStart class. The override annotation shows that the code below the annotation belongs to the parent Application class. The implementation of the method that gets proceeded by the annotation override is present below the annotation.

The start method is the main entry for the JavaFX applications, as main is the entry location for the Java applications. The main method gets first called when the Application or main thread gets initialized.

The function takes Stage as the parameter. The Stages denotes the primary step or view and gets loaded when the application launches in the applet viewer. It also throws Exception that gets defined along with the method.

The first statement inside the method is to load the XML file. The FXMLLoader class loads an object hierarchy from the XML object model. It gets used to bring the object hierarchy from an FXML document into a Parent instance. It takes the parameter as the URL to the location where the XML document hierarchy is present.

The resultant gets stored in a Parent class instance that holds the subtypes in the graph format. The Scene class present in the JavaFX library is the container unit that stores all the data in a graph view. The background of the scene gets filled by the specified property. The instance of Stage class gets created and can get used with other properties.

Below mentioned are the properties used to display the scene over the browser.

• The setScene method makes its use to specify the scene and gets used along with the stage instance variable.
• The setTitle function gets used to set scene title present over the browser. The show function gets used to populate the scene over the stage.

Below is the output for the above code block.

In the output shown above, the issue gets raised at the parameter position that uses the FXMLLoader class to load the XML object, but it returns a null value. In simple words, the getResource() method does not locate the path provided in the function parameter.

Hence, the null value populates NullPointerException, which is a type of runtime exception. And are handled by giving an absolute path where the file can get located. The stack trace often shows the line number where the issue starts populating. The target must be correct when get given in the load parameter.

Hence the given solution to the problem is below.

1. Give the absolute path to the location where the file gets present.
2. Add a SonarLint plugin to the Integrated Development Environment that helps in evaluating or handling the exceptions at the write time.

Rashmi is a professional Software Developer with hands on over varied tech stack. She has been working on Java, Springboot, Microservices, Typescript, MySQL, Graphql and more. She loves to spread knowledge via her writings. She is keen taking up new things and adopt in her career.

Источник

JavaFX «Exception in Application start method»

Сейчас я создаю свой первый JavaFX проект. Назначение данного класса — вывод экранной формы:

Но код не компилируется из-за следующей ошибки:

В качестве среды разработки я использую IntelliJ IDEA Ultimate Edition 2017.1

4 ответа 4

В getResource в качестве разделителя используется / , а не . . Таким образом вместо loader.setLocation(Main.class.getResource(«/com.eit.main.view/MainView.fxml»)); должно быть loader.setLocation(Main.class.getResource(«/com/eit/main/view/MainView.fxml»));

возникала эта же проблема при запуске на SDK14 c библиотекой javafx 11.0.2. Проблема ушла при смене SDK на версию 1.8

Кроме указанных в другом ответе действий также нужно изменить настройки конфигурации. Run->Edit configurations. ->Main->VM options , в этой графе нужно ввести команды как тут (в графе Add VM options).

Воспроизводил аналогичную ошибку, используя Java 11 & Java FX 11 & Intelij IDEA 2021.1.1 :

И проблема была в том, что при дефолтном генерировании JavaFX проекта средой разработки файл fxml был расположен в директории:

когда перенёс fxml файл по совету тут и тут в:

и в start() методе прописал:

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Exception in Application start method java.lang.reflect.InvocationTargetException

I am just starting out with JavaFX, and I am trying to build a simple application with a label, text field and button which, when clicked, sets the label’s value to that of the text field’s. Everything was going well until I connected the controller to the Main file. Here’s my code:

I have tried multiple answers found on StackOverflow, but all that I have found were from 2 years ago and did not make any positive effect on my code.

EDIT: Stack trace here:

14 Answers 14

For anyone who has this exact same problem in the future, as James_D and the other answer contributors mentioned, removing the «/» at the beginning of the path fixes the problem so use

This problem can also occure even when the path is completely right.

When you create the fxml file in an Updated IDE.

Then use an older JavaFX Scene Builder to design it.

Solution :

Create the fxml file in JavaFX Scane Builder

Design the fxml file in JavaFX Scane Builder then copy this to the IDE or Project.

I also met this case, you please follow me hope to succeed: Tool> Options> Java> JavaFX> Scenne Buider Home> Change Link. Your route to Scenne Buider is unsuitable, it took me hours to find, it is time consuming but it will be a matter of always important when starting JavaFX.

Perform the following operation

Remove / from in front of .fxml file name. I think it should work. It solved the same error for me.

Location is not set.
This exception states that your FXML file is unreachable by the code. If you have your fxml file inside any package then specify it with the package name.

i’ve had the same problem with the CORRECT PATH i was working in scene builder 8.5 i upgraded it to 11.0 and now its working (i’ve redesigned all the GUI).

Another cause might be missing VM options:

The same problem happened to me. It’s because of maven library. I have different version of jfoenix library in scene builder jfoenix:0.1.8 and in IDE jfoenix:9.0.9.so i downloaded the same version in both and it worked for me.

And also for the nullpointer exception this code worked for me:

The fxml file and Main is in same package.

I’ve been looking through this thread and the answers but the cases are a bit different for me

the code written in the main file is not as mentioned like this:

the code in my case is like this:

and I encountered the same error(approx.)

1 : Add Module Path and modules to your VM Options by below command : —module-path

it should be resolve by above method , if not resolved then in next step

2: create a seperate fxml and add it in your project , it will work .

To reply comment from that’s plain wrong .. – kleopatra May seems like that to you, but with same Exception in Application start method java.lang.reflect.InvocationTargetException with .getResource(fxml + «.fxml») as a trigger under JavaFx8 version, that resolve the issue for me and It’s the solution, so your comment being plain wrong is personal to issue you and not general. To some it’s just the solution they need.

Which is to replace .getResource() with File Class that returns the same URL and the problem solved. There’s no need to worry about adding / to the file path or using a relative or absolute file path as long as the file path is valid — check f.exist to be sure. I posted what I’ve tried and solved after following all possibly thread answers here on this platform with no valid result. This code below solved the issue for me, so if it’s plain wrong for you as commented earlier -kleopatra, that’s OK. It’s not for me.

.getResource(«MainWindowView.fxml»)); and .getResource(fxml + «.fxml»));

is the problem, known to raise NullPointer and other File not found Exception even when the file path is perfectly valid, get rid of it by using File Class that return same URL value as stated earlier and your code should work fine.

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Источник

Exception in Application start method

I am trying to load the FXML file and show it as an application window, but i get an exception. The FXML file was created by the FXML Scene Builder.

screenshot of structure:

1 Answer 1

The root cause of the exception you are getting is a NullPointerException with the detail message «Location is required.».

I am not going to guide you how to read stack traces, please refer to this question instead.

You are getting the «location is required» error because you are passing null into the FXMLLoader.load() method. The null value must obviously come from the getResource() call. From the Class.getResource() documentation:

Returns:
A URL object or null if no resource with this name is found

So the reason why you are getting the exception has to be that the resource with the given name cannot be found.

Please validate the following:

If you are using the standard eclipse project layout: Make sure you placed the sample.fxml into the same directory as the Sup.java file

If you are using a maven-like directory structure where there are different directories for resources and sources, make sure the sample.fxml is in the resource folder and in the same directory like the source file.

Example: Your source file Sup.java is placed in src/main/java/com/example/Sup.java . Place the sample.fxml file into src/main/resources/com/example/sample.fxml .

If you are using eclipse, clean and rebuild your project. Build tools have similar alternatives (or just delete the build / out directory)

Источник

Application Start Method exception — JavaFX

I would like to say that I have looked a lot in the SO and none of the posts helped me, so I am asking again.

I’m trying to make a login screen, but I still get the same exception. My directory structure looks like this: check here

My code looks like this:

This is the exception I get:

Everything I’ve read so far has said «That’s why FXML can not find the controller!», So I checked and it’s really all right. Here is the controler statement:

I think this information can be requested:

• Java version: 8 (Oracle)
• IDE: IntelliJ Community

GUI made in GluonHQ SceneBuilder.

2 Answers 2

In fact, you’re getting a NPE. Try to debug, then, you can try this:

There is a couple ways to do this. I prefer method 1, since it seems more straightforward to me.

To load a resource you need to know the path. The controllers know their own path, so I use them.

For instance, if I have a heirarchy of java/hypnic/jerk/controllers/ with a MainController.java file in it, and I want to load an FXML file that will use this java file as its controller, I put it in resources/hypnic/jerk/controllers/ . Then, when I call FXMLLoader.load(); I do it this way:

From what I understand and how I see it, this tells the loader to use the path set forth by MainController and grab the mainScreen.fxml file from the path there.

This is, in my opinion, the easiest way to do it since it forces you to keep naming conventions AND you know where each FXML file is for the associated controller file.

You can also use pathing to find it, in your case, your loginScene.fxml is in the fxml/ folder, so from Main I would do

The ../ means, go up one directory/folder. So depending on how may items you have blacked out, remember each . is a new folder in that name, you need to add a ../ until you are back to the java folder.

Lets use your example with a path of java/br/com/one/two/three/main/ . Since your code is saying getClass().getResource(«fxml/loginScene.fxml») you are looking for that file in the resources/br/com/one/two/three/fxml/ folder. The path is based off the calling class Main.java , so it can’t find it because the path in resources doesn’t exist.

So you need to back out of those dirs by using ../ until you get to it. each ../ represents another tier up. So in this case, if I did my math correctly, you would need 5 ../ in order to find the fxml/loginScene.fxml file. So the end result would be

Now remember this is just an explanation and you will have to adapt it on your own.

Источник

Dear Friends,

I am trying to develop javafx programs, here is an unknown exception I got:

ant -f C:\Users\haris\Documents\NetBeansProjects\fxlogin jfxsa-run
init:
Deleting: C:UsersharisDocumentsNetBeansProjectsfxloginbuildbuilt-jar.properties
deps-jar:
Updating property file: C:UsersharisDocumentsNetBeansProjectsfxloginbuildbuilt-jar.properties
compile:
Detected JavaFX Ant API version 1.2
jfx-deployment:
jar:
Copying 12 files to C:UsersharisDocumentsNetBeansProjectsfxlogindistrun993276176
jfx-project-run:
Executing com.javafx.main.Main from C:UsersharisDocumentsNetBeansProjectsfxlogindistrun993276176fxlogin.jar using platform C:Program FilesJavajdk1.7.0_21/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:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at com.javafx.main.Main.launchApp(Main.java:642)
at com.javafx.main.Main.main(Main.java:805)
Caused by: java.lang.RuntimeException: Exception in Application start method
at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:403)
at com.sun.javafx.application.LauncherImpl.access$000(LauncherImpl.java:47)
at com.sun.javafx.application.LauncherImpl$1.run(LauncherImpl.java:115)
at java.lang.Thread.run(Thread.java:722)
Caused by: java.lang.NullPointerException
at fxlogin.Fxlogin.start(Fxlogin.java:70)
at com.sun.javafx.application.LauncherImpl$5.run(LauncherImpl.java:319)
at com.sun.javafx.application.PlatformImpl$5.run(PlatformImpl.java:215)
at com.sun.javafx.application.PlatformImpl$4$1.run(PlatformImpl.java:179)
at com.sun.javafx.application.PlatformImpl$4$1.run(PlatformImpl.java:176)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.application.PlatformImpl$4.run(PlatformImpl.java:176)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.access$100(WinApplication.java:29)
at com.sun.glass.ui.win.WinApplication$3$1.run(WinApplication.java:73)
… 1 more
Java Result: 1
Deleting directory C:UsersharisDocumentsNetBeansProjectsfxlogindistrun993276176
jfxsa-run:
BUILD SUCCESSFUL (total time: 9 seconds)

here is my code

/*
Document : Login
Created on : Jun 7, 2013, 11:11:36 PM
Author : haris
Description:
Purpose of the stylesheet follows.
*/

.root {
display: block;
-fx-background-image: url(«background.jpg»);

}

java class

/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package fxlogin;

import javafx.scene.control.Button;
import javafx.application.Application;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.PasswordField;
import javafx.scene.control.TextField;
import javafx.stage.Stage;
import javafx.scene.layout.GridPane ;
import javafx.scene.text.Font;
import javafx.scene.text.FontWeight;
import javafx.scene.text.Text;
import javafx.geometry.Insets;
import javafx.scene.layout.HBox;
/**
*
* @author haris
*/

public class Fxlogin extends Application {

@Override
public void start(Stage primaryStage) {

primaryStage.setTitle(«JavaFX Welcome»);

GridPane grid = new GridPane();
grid.setAlignment(Pos.CENTER);
grid.setHgap(10);
grid.setVgap(10);
grid.setPadding(new Insets(25, 25, 25, 25));

Text scenetitle = new Text(«Welcome»);
scenetitle.setFont(Font.font(«Tahoma», FontWeight.NORMAL, 20));
grid.add(scenetitle, 0, 0, 2, 1);

Label userName = new Label(«User Name:»);
grid.add(userName, 0, 1);

TextField userTextField = new TextField();
grid.add(userTextField, 1, 1);

Label pw = new Label(«Password:»);
grid.add(pw, 0, 2);

PasswordField pwBox = new PasswordField();
grid.add(pwBox, 1, 2);

Button btn = new Button(«Sign in»);
HBox hbBtn = new HBox(10);
hbBtn.setAlignment(Pos.BOTTOM_RIGHT);
hbBtn.getChildren().add(btn);
grid.add(hbBtn, 1, 4);
final Text actiontarget = new Text();
grid.add(actiontarget, 1, 6);

Scene scene = new Scene(grid, 300, 275);
primaryStage.setScene(scene);
scene.getStylesheets().add(Fxlogin.class.getResource(«Login.css»).toExternalForm());
primaryStage.show();
}

/**
* The main() method is ignored in correctly deployed JavaFX application.
* main() serves only as fallback in case the application can not be
* launched through deployment artifacts, e.g., in IDEs with limited FX
* support. NetBeans ignores main().
*
* @param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}
}

Why do I get this exception??? thank you

Edited by: user8709910 on Jun 7, 2013 1:45 PM