Need Help Please. Cannot run main. Exception in Application start method.

Question

So I followed along in the video and did everything step by step the same. When I try to run I get this:

Exception in Application start method
Exception in thread "Thread-3" java.lang.IncompatibleClassChangeError
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$155(LauncherImpl.java:182)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
    at com.teamtreehouse.pomodoro.Main.start(Main.java:15)
    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$162(LauncherImpl.java:863)
    at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$175(PlatformImpl.java:326)
    at com.sun.javafx.application.PlatformImpl.lambda$null$173(PlatformImpl.java:295)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl.lambda$runLater$174(PlatformImpl.java:294)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
    ... 1 more
Exception running application com.teamtreehouse.pomodoro.Main
Disconnected from the target VM, address: '127.0.0.1:50282', transport: 'socket'

Process finished with exit code 1

Main.java

package com.teamtreehouse.pomodoro;

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

public class Main extends Application {

    @Override
    public void start(Stage primaryStage) throws Exception {
        // Load the font
        Font.loadFont(getClass().getResource("/fonts/VarelaRound-Regular.ttf").toExternalForm(), 10);
        Parent root = FXMLLoader.load(getClass().getResource("/fxml/home.fxml"));
        primaryStage.setScene(new Scene(root, 500, 500));
        primaryStage.setResizable(false);
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}

Home.java

package com.teamtreehouse.pomodoro.controllers;

import com.teamtreehouse.pomodoro.model.Attempt;
import com.teamtreehouse.pomodoro.model.AttemptKind;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.scene.control.Label;
import javafx.scene.layout.VBox;


public class Home {
    @FXML
    private VBox container;

    @FXML
    private Label title;

    private Attempt mCurrentAttempt;

    private void prepareAttempt(AttemptKind kind) {//call prepare attempt
        clearAttemptStyles();//starts off with a clear slate
        mCurrentAttempt = new Attempt(kind, "");//set the current attempt to a new one
        addAttemptStyle(kind);//add style for the kind passed it
        title.setText(kind.getDisplayName());//changes title to the kind focus or break

    }

    private void addAttemptStyle(AttemptKind kind) {
        container.getStyleClass().add(kind.toString().toLowerCase());//returns a list
    }

    private void clearAttemptStyles() {//method to loop through attempt kinds and clear
        for (AttemptKind kind : AttemptKind.values()) {
            container.getStyleClass().remove(kind.toString().toLowerCase());
        }
    }

    public void DEBUG(ActionEvent actionEvent) {
        System.out.println("Hi Mom");
    }
}

Attempt.java

package com.teamtreehouse.pomodoro.model;


public class Attempt {
    private String mMessage;
    private int mRemainingSeconds;
    private AttemptKind mKind;

    public Attempt(AttemptKind kind, String message) {
        mMessage = message;
        mKind = kind;
        mRemainingSeconds = kind.getTotalSeconds();
    }

    public String getMessage() {
        return mMessage;
    }

    public int getRemainingSeconds() {
        return mRemainingSeconds;
    }

    public AttemptKind getKind() {
        return mKind;
    }

    public void setMessage(String message) {
        mMessage = message;
    }
}

AttemptKind.java

package com.teamtreehouse.pomodoro.model;


public enum AttemptKind {
    FOCUS(25 * 60, "Focus time"),//enum and (totalseconds, display name)
    BREAK(5 * 60, "Break time");

    private int mTotalSeconds;
    private String mDisplayName;

    AttemptKind(int totalSeconds, String displayName) {//enum constructor
        mTotalSeconds = totalSeconds;
        mDisplayName = displayName;
    }

    public int getTotalSeconds() {
        return mTotalSeconds;
    }

    public String getDisplayName() {
        return mDisplayName;
    }
}

home.fxml

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

<?import javafx.scene.control.*?>
<?import javafx.scene.image.Image?>
<?import javafx.scene.image.ImageView?>
<?import javafx.scene.layout.*?>
<?import javafx.scene.shape.SVGPath?>
<VBox stylesheets="/resources/css/main.css"
      xmlns="http://javafx.com/javafx/8"
      xmlns:fx="http://javafx.com/fxml"
      fx:controller="com.teamtreehouse.pomodoro.controllers.Home"
      fx:id="container">
    <children>
        <Button fx:id="DEBUG" onAction="#DEBUG"></Button>

        <Label fx:id="title" text="Pomodoro"/>

        <Label fx:id="time" text="00:00"/>

        <HBox styleClass="buttons">
            <children>
                <StackPane>
                    <children>
                        <StackPane styleClass="nested-action,play">
                            <children>
                                <HBox styleClass="svg-container">
                                    <SVGPath styleClass="svg"
                                             content="M1.6 17C1 17 0 16.2 0 15.6V1.3C0 .1 2.2-.4 3.1.4l8.2 6.4c.5.4.8 1 .8 1.7 0 .6-.3 1.2-.8 1.7l-8.2 6.4c-.5.2-1 .4-1.5.4z"/>
                                </HBox>
                                <Button text="Resume"/>
                            </children>
                        </StackPane>

                        <StackPane styleClass="nested-action,pause">
                            <children>
                                <HBox styleClass="svg-container">
                                    <SVGPath styleClass="svg"
                                             content="M10.2 17c-1 0-1.8-.8-1.8-1.8V1.8c0-1 .8-1.8 1.8-1.8S12 .8 12 1.8v13.4c0 1-.8 1.8-1.8 1.8z" />
                                    <SVGPath styleClass="svg"
                                             content="M10.2 17c-1 0-1.8-.8-1.8-1.8V1.8c0-1 .8-1.8 1.8-1.8S12 .8 12 1.8v13.4c0 1-.8 1.8-1.8 1.8z" />
                                </HBox>
                                <Button text="Pause"/>
                            </children>
                        </StackPane>
                    </children>
                </StackPane>

                <StackPane styleClass="nested-action,restart">
                    <children>
                        <HBox styleClass="svg-container">
                            <SVGPath styleClass="svg"
                                     content="M21 2.9C19.1 1 16.6 0 13.9 0c-1.1 0-2 .9-2 1.9s.9 1.9 2 1.9c1.7 0 3.2.6 4.4 1.8 2.4 2.4 2.4 6.3 0 8.7-1.2 1.2-2.7 1.8-4.4 1.8-1.7 0-3.2-.6-4.4-1.8-1.8-1.8-2.3-4.4-1.4-6.7L9.3 10c.2.4.5.7.9.8.4.1.8.1 1.2-.1.8-.4 1.1-1.3.8-2.1L10 4.3c0-.5-.2-1-.6-1.4l-.1-.1-.1-.2c-.2-.4-.5-.7-.9-.8-.4-.1-.8-.1-1.2.1L.9 4.8C.1 5.2-.2 6.1.2 6.9c.2.4.5.7.9.8.4.1.8.1 1.2-.1l2-.9c-1.2 3.5-.4 7.6 2.4 10.4C8.6 19 11.2 20 13.9 20s5.3-1 7.2-2.9C25 13.2 25 6.8 21 2.9z"/>
                        </HBox>
                        <Button text="Restart"/>
                    </children>
                </StackPane>
            </children>
        </HBox>

        <TextArea fx:id="message" promptText="What are you doing?"/>

        <ImageView>
            <image>
                <Image url="/resources/images/pomodoro.png"/>
            </image>
        </ImageView>

    </children>
</VBox>

I have not touched any code other than these. The only difference I can say is that in the video the project is titled Pomodoro, but when I opened the project from existing sources it took the s3v1 name. Is this my problem? Any help would be appreciated so I can continue.

Answer 1 · 2017-11-22T12:16:52Z

November 22, 2017 12:16pm

A little late to the party, but the solution is Robin's answer in this thread: https://teamtreehouse.com/community/how-do-i-solve-this-nullexception-in-main-method

Thought I'd share it, since I've been at it for a century before finding it :P

Answer 2 · 2017-03-02T15:03:54Z

March 2, 2017 3:03pm

Not going to say I know whats happening here But I'm looking at the code on line 15 in the main class and wonder if its anything to do with the font being understood by the IDE.

or put another way. IntelliJ doesn't seem to understand what a TrueType Font is

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sinan muyesser

sinan muyesser

Need Help Please. Cannot run main. Exception in Application start method.

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