Question

我在Netbeans中创建了Java FXML应用程序，默认情况下，它使用按钮创建了一个场景。我尝试运行它，但它引发了如下几种异常：

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$FXHelper.main(LauncherHelper.java:767)
Caused by: java.lang.RuntimeException: Exception in Application start method
at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:917)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$154(LauncherImpl.java:182)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.NullPointerException: Location is required.
at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3207)
at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3175)
at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3148)
at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3124)
at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3104)
at javafx.fxml.FXMLLoader.load(FXMLLoader.java:3097)
at timetable.Main.start(Main.java:22)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$161(LauncherImpl.java:863)
at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$174(PlatformImpl.java:326)
at com.sun.javafx.application.PlatformImpl.lambda$null$172(PlatformImpl.java:295)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.application.PlatformImpl.lambda$runLater$173(PlatformImpl.java:294)
at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$147(WinApplication.java:177)
... 1 more
Exception running application timetable.Main
C:\Users\This PC\Documents\NetBeansProjects\Timetable\nbproject\build-impl.xml:1052: The following error occurred while executing this line:
C:\Users\This PC\Documents\NetBeansProjects\Timetable\nbproject\build-impl.xml:806: Java returned: 1

代码如下：

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

    Scene scene = new Scene(root);

    stage.setScene(scene);
    stage.show();

我是JavaFX的初学者，我真的不太了解此错误的来源。

P.S。我可以使用Scene Builder打开fxml文件

Answer 1

由于您是JavaFX的新手，所以也许您不知道可以不用编写.fxml文件的JavaFX应用程序。您还提到您正在使用 Scene Builder 。在我看来，向导不是初学者学习的好方法。就是说，您的问题出在方法getResource()上，找不到您的.fxml文件。从您发布的堆栈跟踪中，您正在类getResource()中的方法start()中调用方法timetable.Main。由于您仅传递了没有路径的文件名，因此.fxml文件必须与文件Main.class位于同一目录中，而文件Main.class将位于目录timetable中。但是，我无法告诉您timetable的父目录是什么。

尝试运行基本javafx项目时出现java.lang.reflect.InvocationTargetException错误

1 个答案: