启动使用fxml文件的应用程序时，应用程序启动方法异常

Question

我是javafx的新手，我从未使用过fxml文件

我已经尝试在这里搜索解决方案，但没有找到任何可以解决我问题的方法。

可能有用的信息：

文件名正确，fxml文件与应用程序位于同一软件包中。

当尝试启动我的javafx应用程序时，出现以下错误：

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:497)
    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:497)
    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$156(LauncherImpl.java:182)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.IllegalStateException: Location is not set.
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2434)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2409)
    at GUIs.DebuggingGUI.start(DebuggingGUI.java:39)
    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$163(LauncherImpl.java:863)
    at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$176(PlatformImpl.java:326)
    at com.sun.javafx.application.PlatformImpl.lambda$null$174(PlatformImpl.java:295)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl.lambda$runLater$175(PlatformImpl.java:294)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.lambda$null$149(WinApplication.java:191)
    ... 1 more
Exception running application GUIs.DebuggingGUI

该应用程序的代码为：

package GUIs;

import ADTs.Adress;
import Observer.*;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.image.ImageView;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
import javafx.scene.image.Image;
import javafx.stage.FileChooser;
import java.io.File;
import java.io.IOException;

import Controller.*;
import sun.security.ssl.Debug;

//ToDo with scene builder
public class DebuggingGUI extends Application{

    public static void main(String[] args) {

        launch(args);

    }

    @Override
    public void start(Stage primaryStage) throws Exception {

        try {
            FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("DebuggingView.fxml"));
            Parent root = (Parent) fxmlLoader.load();
            primaryStage.setTitle("Debugging environment for Apollo");
            primaryStage.setScene(new Scene(root, 1800, 800));
            primaryStage.show();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

}

这是fxml文件：

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.image.*?>
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>


<BorderPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1">
   <top>
      <HBox prefHeight="100.0" prefWidth="200.0" BorderPane.alignment="CENTER" />
   </top>
   <center>
      <ImageView fx:id="MainView" fitHeight="150.0" fitWidth="200.0" pickOnBounds="true" preserveRatio="true" BorderPane.alignment="CENTER" />
   </center>
   <left>
      <VBox prefHeight="200.0" prefWidth="100.0" BorderPane.alignment="CENTER">
         <children>
            <Button fx:id="StepButton" alignment="CENTER" mnemonicParsing="false" onAction="#StepVM" text="Step" />
         </children>
      </VBox>
   </left>
</BorderPane>