[SOLVED] Loading a FXML into borderpane center

Good evening guys,

I am playing around with JavaFX. The aim is to load a prepared fxml into the center element of a borderpane on button click. Unfortunately, I am getting the following error:

Caused by: javafx.fxml.LoadException: 
/D:/Coden/Eclipse%20Workspace/Project%20Tango001/bin/application/Page1Gui.fxml:8

	at javafx.fxml.FXMLLoader.constructLoadException(Unknown Source)
	at javafx.fxml.FXMLLoader.access$700(Unknown Source)
	at javafx.fxml.FXMLLoader$ValueElement.processAttribute(Unknown Source)
	at javafx.fxml.FXMLLoader$InstanceDeclarationElement.processAttribute(Unknown Source)
	at javafx.fxml.FXMLLoader$Element.processStartElement(Unknown Source)
	at javafx.fxml.FXMLLoader$ValueElement.processStartElement(Unknown Source)
	at javafx.fxml.FXMLLoader.processStartElement(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.load(Unknown Source)
	at application.MainGUIController.LadeCenterNeu(MainGUIController.java:19)
	... 57 more
Caused by: java.lang.ClassNotFoundException: Page1GUIController.java
	at java.net.URLClassLoader$1.run(Unknown Source)
	at java.net.URLClassLoader$1.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(Unknown Source)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	... 71 more

Please find my simple code as follows:

Main.java:

//*** Main.java

package application;
	
import javafx.application.Application;
import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.layout.BorderPane;
import javafx.fxml.FXMLLoader;


public class Main extends Application {
	@Override
	public void start(Stage primaryStage) {
		try {
			BorderPane root = (BorderPane)FXMLLoader.load(getClass().getResource("MainGUI.fxml"));
			Scene scene = new Scene(root,400,400);
			scene.getStylesheets().add(getClass().getResource("application.css").toExternalForm());
			primaryStage.setScene(scene);
			primaryStage.show();
		} catch(Exception e) {
			e.printStackTrace();
		}
	}
	
	public static void main(String[] args) {
		launch(args);
	}
}

MainGui.fxml:

//*** MainGui.fxml

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

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

<BorderPane id="maincontent" fx:id="maincontent" maxHeight="344.0" maxWidth="600.0" minHeight="344.0" minWidth="600.0" prefHeight="344.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="application.MainGUIController">
   <top>
      <Pane prefHeight="72.0" prefWidth="600.0" style="-fx-background-color: #00567F;" BorderPane.alignment="CENTER">
         <children>
            <Button layoutX="274.0" layoutY="24.0" mnemonicParsing="false" onAction="#LadeCenterNeu" text="Button" />
         </children></Pane>
   </top>
   <left>
      <Pane prefHeight="200.0" prefWidth="98.0" style="-fx-background-color: #33677F;" BorderPane.alignment="CENTER" />
   </left>
   <center>
      <Pane id="MainGUICenter" prefHeight="200.0" prefWidth="200.0" style="-fx-background-color: #4CC5FF;" BorderPane.alignment="CENTER">
         <children>
            <Label layoutX="169.0" layoutY="92.0" text="Initialer Inhalt" textAlignment="CENTER" />
         </children>
      </Pane>
   </center>
   <right>
      <Pane prefHeight="200.0" prefWidth="92.0" style="-fx-background-color: #33677F;" BorderPane.alignment="CENTER" />
   </right>
   <bottom>
      <Pane prefHeight="72.0" prefWidth="600.0" style="-fx-background-color: #00567F;" BorderPane.alignment="CENTER" />
   </bottom>
</BorderPane>

MainGuiController.java:

//*** MainGuiController.java

package application;

import java.io.IOException;

import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.scene.layout.Pane;


public class MainGUIController {
	
	@FXML
	Pane maincontent;
	
	@FXML
	private void LadeCenterNeu(ActionEvent event) throws IOException {
		maincontent.getChildren().clear();
		maincontent.getChildren().add(FXMLLoader.load(getClass().getResource("Page1Gui.fxml")));
		System.out.println("Load!");
	}
	
}

Page1Gui.fxml:

//*** Page1Gui.fxml

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

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

<AnchorPane prefHeight="425.0" prefWidth="545.0" style="-fx-background-color: #111111;" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="Page1GUIController.java">
   <children>
      <Pane layoutX="-169.0" layoutY="-176.0" prefHeight="200.0" prefWidth="200.0" />
      <Label layoutX="259.0" layoutY="204.0" text="Inhalt 2" />
   </children>
</AnchorPane>

Page1GuiController.java:

package application;

public class Page1GUIController {

}

Your help is much appreciated!