Why am I getting a javafx.fxml.LoadException in Java

Question

I am making Sudoku for my School-Project and need to open I new Window where the Highscores will be listed, but every time i click on the MenuItem the console just throws out Errors and i dont know what i could do.

I already tried to look for something in the internet but everything I tried led to the same Errors

package controller;

import java.io.IOException;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.event.EventHandler;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.fxml.Initializable;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
import javafx.scene.control.Button;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.text.Font;
import javafx.stage.Modality;
import javafx.stage.Stage;
import model.GameBoard;

public class Controller implements Initializable {

    @FXML
    Button button_one;
    @FXML
    Button button_two;
    @FXML
    Button button_three;
    @FXML
    Button button_four;
    @FXML
    Button button_five;
    @FXML
    Button button_six;
    @FXML
    Button button_seven;
    @FXML
    Button button_eight;
    @FXML
    Button button_nine;
    @FXML
    Canvas canvas;

    GameBoard gameboard;

    int psr; // ausgewählte reihe
    int psc; // ausgewählte spalte



    @Override
    public void initialize(URL location, ResourceBundle resources) {
        gameboard = new GameBoard();
        psr = 0;
        psc = 0;
        GraphicsContext context = canvas.getGraphicsContext2D();
        try {
            drawOnCanvas(context);
        } catch (IOException e) {

            e.printStackTrace();
        }

    }

    public void drawOnCanvas(GraphicsContext context) throws IOException {
        context.clearRect(0, 0, 450, 450);
        for (int row = 0; row < 9; row++) {
            for (int col = 0; col < 9; col++) {
                int posy = row * 50 + 2;
                int posx = col * 50 + 2;
                int width = 46;
                context.setFill(Color.LIGHTGRAY);
                context.fillRoundRect(posx, posy, width, width,10,10);
            }
        }
        context.setStroke(Color.RED);
        context.setLineWidth(2);
        context.strokeRoundRect(psc * 50 + 2, psr * 50 + 2, 46, 46, 10, 10);

        int[][] initial = gameboard.getInitial();
        for (int row = 0; row < 9; row++) {
            for (int col = 0; col < 9; col++) {
                int posy = row * 50 + 30;
                int posx = col * 50 + 20;
                context.setFill(Color.BLACK);
                context.setFont(new Font(20));
                if (initial[row][col] != 0) {
                    context.fillText(initial[row][col] + "", posx, posy);
                }

            }
        }

        int[][] player = gameboard.getPlayer();
        for(int row = 0; row < 9;row++) {
            for(int col = 0; col < 9; col++) {
                int posy = row * 50 + 30;
                int posx = col * 50 + 20;
                context.setFill(Color.RED);
                context.setFont(new Font(20));
                if(player[row][col] != 0) {
                    context.fillText(player[row][col] + "", posx, posy);
                }
            }
        }


        //Die vier Linien für die 3x3 Trennung
        context.setStroke(Color.BLACK);
        context.strokeLine(450, 150, 0, 150);
        context.strokeLine(450, 300, 0, 300);
        context.strokeLine(150, 0, 150, 450);
        context.strokeLine(300, 0, 300, 450);
        context.setLineWidth(3);


        if(gameboard.checkSuccess()) {
            context.clearRect(0, 0, 450, 450);
            context.setFill(Color.GREEN);
            context.setFont(new Font(36));
            context.fillText("SUPER!", 150, 200);
            newWindow();






        }



    }

    public void canvasMouseClick() throws IOException{
        canvas.setOnMouseClicked(new EventHandler<MouseEvent>() {

            @Override
            public void handle(MouseEvent event) {
                int mousex = (int) event.getX();
                int mousey = (int) event.getY();

                psr = (int) (mousey / 50);
                psc = (int) (mousex / 50);

                // System.out.println(psr + "," + psc);

                try {
                    drawOnCanvas(canvas.getGraphicsContext2D());
                } catch (IOException e) {

                    e.printStackTrace();
                }

            }
        });

    }







public void button1pressed() throws IOException{
                gameboard.modifyPlayer(1, psr, psc);
                drawOnCanvas(canvas.getGraphicsContext2D());

            }




public void button2pressed() throws IOException{
            gameboard.modifyPlayer(2, psr, psc);
            drawOnCanvas(canvas.getGraphicsContext2D());

        }







public void button3pressed() throws IOException{
            gameboard.modifyPlayer(3, psr, psc);
            drawOnCanvas(canvas.getGraphicsContext2D());

           }





 public void button4pressed() throws IOException{
            gameboard.modifyPlayer(4, psr, psc);
            drawOnCanvas(canvas.getGraphicsContext2D());

         }




public void button5pressed() throws IOException{
            gameboard.modifyPlayer(5, psr, psc);
            drawOnCanvas(canvas.getGraphicsContext2D());

         }





public void button6pressed() throws IOException{
            gameboard.modifyPlayer(6, psr, psc);
            drawOnCanvas(canvas.getGraphicsContext2D());
        }





public void button7pressed() throws IOException{
            gameboard.modifyPlayer(7, psr, psc);
            drawOnCanvas(canvas.getGraphicsContext2D());
        }





public void button8pressed() throws IOException {
            gameboard.modifyPlayer(8, psr, psc);
            drawOnCanvas(canvas.getGraphicsContext2D());
        }





public void button9pressed() throws IOException {
            gameboard.modifyPlayer(9, psr, psc);
            drawOnCanvas(canvas.getGraphicsContext2D());
        }





    public void neuesSpiel() throws IOException {
        gameboard = new GameBoard();
        psr = 0;
        psc = 0;
        GraphicsContext context = canvas.getGraphicsContext2D();
        drawOnCanvas(context);
    }

    public void newWindow() throws IOException {

        try {
            FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("/controller/highscore.fxml"));
            VBox root1 = (VBox) fxmlLoader.load();
            Stage stage = new Stage();
            stage.setScene(new Scene(root1));  
            stage.show();
        } catch(Exception e) {
            e.printStackTrace();
        }


    }



}

StackTrace:

Mai 21, 2019 5:31:30 PM javafx.fxml.FXMLLoader$ValueElement processValue
WARNING: Loading FXML document with JavaFX API of version 11.0.1 by JavaFX runtime of version 8.0.181
Mai 21, 2019 5:31:32 PM javafx.fxml.FXMLLoader$ValueElement processValue
WARNING: Loading FXML document with JavaFX API of version 11.0.1 by JavaFX runtime of version 8.0.181

javafx.fxml.LoadException: 
/C:/Users/Luka%20Lajic/eclipse-workspace/Sudoku/bin/controller/highscore.fxml

at javafx.fxml.FXMLLoader.constructLoadException(FXMLLoader.java:2601)
at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2579)
at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2441)
at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2409)
at controller.Controller.newWindow(Controller.java:223)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at sun.reflect.misc.Trampoline.invoke(Unknown Source)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at sun.reflect.misc.MethodUtil.invoke(Unknown Source)
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1771)
at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1657)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49)
at javafx.event.Event.fireEvent(Event.java:198)
at javafx.scene.control.MenuItem.fire(MenuItem.java:462)
at com.sun.javafx.scene.control.skin.ContextMenuContent$MenuItemContainer.doSelect(ContextMenuContent.java:1405)
at com.sun.javafx.scene.control.skin.ContextMenuContent$MenuItemContainer.lambda$createChildren$343(ContextMenuContent.java:1358)
at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
at javafx.event.Event.fireEvent(Event.java:198)
at javafx.scene.Scene$MouseHandler.process(Scene.java:3757)
at javafx.scene.Scene$MouseHandler.access$1500(Scene.java:3485)
at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1762)
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2494)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:394)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:295)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$353(GlassViewEventHandler.java:432)
at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:389)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:431)
at com.sun.glass.ui.View.handleMouseEvent(View.java:555)
at com.sun.glass.ui.View.notifyMouse(View.java:937)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$147(WinApplication.java:177)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NullPointerException
    at controller.Controller.initialize(Controller.java:58)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2548)
    ... 56 more

Does your `Canvas` have an `fx:id="canvas"` attribute in the FXML file? — Slaw, May 21 '19 at 16:13

score 0 · Answer 1 · answered May 21 '19 at 15:58

Caused by: java.lang.NullPointerException
at controller.Controller.initialize(Controller.java:58)

Suggests the error is on line 58 of your Controller class. This seems to be this line:

GraphicsContext context = canvas.getGraphicsContext2D();

and if so, this would happen if canvas was null.

You'll most likely be able to resolve the error by ensuring you have instantiated canvas properly, but if you need further help, you can read more here.

Why am I getting a javafx.fxml.LoadException in Java

1 Answers1